Dredging w/Hydraulic Excavator
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kaveman
20:56:17 Tue
Feb 10 2009
Dredging w/Hydraulic Excavator
This was prompted by an earlier thread that was getting a little off-topic. Give me half an hour or so to upload all the story.

Anyway, purely theoretical at this point, but I felt like doodling with the computer a little today, so here goes,....

First, we clear the vegetation from the area we want to mine.



The mining plan is to dig a series of ponds that we can dredge outside of the active waterway. We start by removing the top layer of material from the holes, flooding the holes, and using a suction dredge to mine the lower layer of gravel and clean bedrock.

kaveman
20:58:44 Tue
Feb 10 2009
Re: Dredging w/Hydraulic Excavator
We bring in the excavator and starting from south to north, we dig a series of shallow ponds 15' wide by 30' long, leaving narrow dikes between the ponds. We backcast the spoil behind the excavator and leave that material for later processing.



Working south, we extend the ponds to full width of 30'x30' and continue to backcast the excavated material.



Then we shut the excavator down and pump water into the holes to create the dredging ponds,..........and bring in the dredge. The dredge is floated in the center pond and the hoses(in this case a twin 6")are crossed over the dike into the south pond. The idea here is to keep the water in the south pond clear enough for dredging while the muddy tailing water dumps into the center pond and filters back through the dike.



kaveman
21:11:29 Tue
Feb 10 2009
Re: Dredging w/Hydraulic Excavator
Once the south pond is dredged of all material and the bedrock cracks cleaned of any gold, the dredge is swapped around to the south pond and the hoses go into the center pond. The dredge tailings from the south pond are the first to go, then the bottom material from the center pond and the cleaning of the bedrock.



Once the center pond is completely dredged, the nozzles can take down the dike between the ponds and clean the bedrock under it.



Then the dredge is moved forward again and the hoses dropped into the north pond where the process repeats.



Eventually we end up with a 30'x90' pond with clean bedrock and nothing but dredge tailings in it. Time to remove the dredge and bring in the gravel plant to run the spoil pile and backfill the hole.




kaveman
21:22:29 Tue
Feb 10 2009
Re: Dredging w/Hydraulic Excavator
Now it's just a matter of walking the excavator and gravel plant up along the pond as we feed the gravel in and discharge oversize and tailings into the pond.






Once all the material has been processed, we bring in the dozer to grade the tails and prepare the ground for replanting. The process can continue in another location or ponds can be added to the chain.



Walt_Anchorage
22:35:33 Tue
Feb 10 2009
Re: Dredging w/Hydraulic Excavator
Seems like a good idea but I have a couple questions. First, after you finish dredging the south pond and move the suction hoses to the middle pond aren’t you going to be reprocessing the same material you just took out of the south pond (or did I miss a step)? Second is will the water filter through the dike fast enough to replenish the water your dredge will be rremoving?

kaveman
23:02:21 Tue
Feb 10 2009
Re: Dredging w/Hydraulic Excavator
Quote: Walt_Anchorage at 22:35:33 Tue Feb 10 2009

Seems like a good idea but I have a couple questions. First, after you finish dredging the south pond and move the suction hoses to the middle pond aren’t you going to be reprocessing the same material you just took out of the south pond (or did I miss a step)? Second is will the water filter through the dike fast enough to replenish the water your dredge will be rremoving?


Exactly right,..........we will need to reprocess the tailings from the south hole in order to clear them from the center hole. My experience with dredging tailings is that they go through the dredge at a pretty good rate since they're loose and there are no oversize rocks to contend with. It takes about 1/10 the time to move the material the second time, so it's work we'll just plan to do. I've got a lot of experience dredging my own tailings,................I always seem to put them in the wrong place.

I'm expecting Dredger to post some info on filters for the dikes, but my guess is that either it'll soak through quickly enough to not overtop the ponds(unlikely), or I'll take a bite out of the dike with the hoe and replace it with loose gravel(most likely because I want the dredge hose going through the dike rather than over it), or, possibly we'll keep a steady flow of fresh water coming into the dredge pond to make up for the unavoidable seepage to the rest of the bar. We've got a 15HP pump supplying a 3" hose at 4-500gpm for intial filling of the ponds, assuming groundwater won't be enough in any particular area.

Yes, good questions. We've been thinking about both of them. Now that Dredger tells me that the dredge pond will remain clear enough to dredge, I'm wondering what it's going to be like when we start dredging the center pond(which acted as a tailing pond for the south pond). Will a day or two of settling be enough, and will we need to worry about kicking the silt back up? If nothing else, we may just have to dredge blind until we get the tailings crossed back over to the south pond. Poor visibility isn't that much of a concern while moving tailings, but it becomes a major concern when moving boulders and cobbles and cleaning bedrock. Hopefully we'll be back in clean water by that time.

kaveman
23:11:13 Tue
Feb 10 2009
Re: Dredging w/Hydraulic Excavator
geowizard,...............I refer to it as 'dredging' because we'll be in full dive gear and we'll be operating a suction dredge, but you're right,.............it really isn't dredging. It certainly won't require a dredge permit, since dredging can only be done in the active waterway and obviously the excavator has no business being there! Underwater highbanking, maybe? It's really just an elaborate, mechanized version of suction high banking.

Our goal is to get a fairly large bulk sample from ground 5-10' deep where the majority of the gold is expected to be on or 'in' the bedrock.

The little dance posted above is my idea of how to get the material dug, piled, dredged, processed and returned with the absolute minimum of handling and machinery movement, taking into account the reach of the hoe and considering that the processing plant needs to be tethered to the river by that 3" line. Whether it'll go as smoothly as I plan I have my doubts, but at least I tried.

pitchak
02:06:00 Wed
Feb 11 2009
Re: Dredging w/Hydraulic Excavator
Been doing that for a couple years now.The top material goes through my big high-banker fed by the mini-excavator.The bedrock we flood by diverting what we need from the creek and clean the bedrock.The bedrock is mostly broken up already by the teeth of the mini.Kinda slow going with a 3 inch dredge,but we get all the gold.We recover lots of nuggets in an area not known for nuggets.Up to 3/4 oz. nuggets.And it's all still considered recreational by DNR.

Heavens_Pavement
06:36:31 Wed
Feb 11 2009
Re: Dredging w/Hydraulic Excavator
@ pitchak what permits did need?
got any pictures of your setup?, sounds cool :smile:

pitchak
22:40:58 Wed
Feb 11 2009
Re: Dredging w/Hydraulic Excavator
Sorry,I don't have pictures.
It's a long story about the permits.I have to get ALL the permits known to man.NOT for the mining,but to keep a shed and outhouse that were on the claims when we got them.LOL.
What I do with my tailings is scoop them out of my way with the ex.My ops too small to handle them again.Water leaves plant and goes thru 500 ft of old tailings with no sediment ever reaching creek.DEC and EPA are happy with how I do things.The Grayling are safe in Deadwood.I could use a bigger dredge,but that would mean more gold,more money,which would mean I would have to get ANOTHER permit to spend it all.

vortxrex
00:18:52 Thu
Feb 12 2009
Re: Dredging w/Hydraulic Excavator
Hello all, Great posting on getting the dredge out into the gravel :smile: Kaveman, how good are you at dredging w/ zero visibility? I know you have all your tailings dumping into another pond (like Dredger showed in an earlier post), BUT you are still going to have some serious visibility problems in the forward hole where you are working IMO.

How much oversize material is there? if you can get a large enough through the nozzle it will be workable, but if there is a lot of oversize it will make 'dredging blind' a challenge.

Trev Alty from NZ had some type of mesh net that he was using to control silt in stagnant water... That might be something to look at?

I like what you & dredger are up to & wish you both the best of luck w/ your operations, but In my experience the Hydraulic Elevator type set-ups have a lot more advantages.

Dave Frank



dredger
01:07:04 Thu
Feb 12 2009
Re: Dredging w/Hydraulic Excavator
Hey kaveman,

Looks great mate, I have a diagrams started but your pics are great,

I am in a hurry so some points of my interest, are,

I plan my sites so that I only disturb one small area at a time, not the hole or large area, I also make it clear to the Authorities in my planning applications that if anything goes wrong, only a ""very small "" area is at little or NO risk, and I also ask for and " get " large reduction in Rehab Bonds, also get gold in ya pocket quicker, also i suggest it is easier on your body if you can be digging for short periods and dredging for short periods, rather then having to dredging continuously long periods,do a hole or area in a few days,

Also, when ever the inspector arrives, I point out the rehab areas, in different stages/time periods of rehab, and stress there is minimum envo FOOT PRINT,

Also you mention a gravel processing unit, for the old tailing's, arrrr, where do I start , ok, as you know this or most gravel processing units / trammels or vibrating screens sluices ect ( and even a good dredge ) cost money to first " have" and two "run" , and process "slowly " , so , I suggest using " only the excavator " , and small water filled holes on bedrock level, to concentrate the heavies from the larger tailing's piles in the bottom of a dredge hole, sort of move the dredge hole to the best source of material, or at least easy reach of the excavator, then use the dredge to process the concentrated heavies in the hole at bedrock level , ??. 2 x 6" nozzle, would work /process well, and the excavator could even remove the tailing's from behind the dredge as the divers dredge,

The reason for suggesting this is it was my experience when digging a dredge and tailing's pond was that I consciously tried to shack or drop the or all gold through the overburden and on to the bedrock, testing the material from the work hole was easily done by allowing lots of people over the years to process /pan/sluice as much as they liked, :confused:, they never found gold in the wormhole overburden , only in the tailing's dam over burden or dam walls,

Another experience of mine was inspecting the first skid mounted tromel in NZ , processing bench placer, there was a problem with silted water escaping from dams on a hill into a creek, 1/2 a mile ( very silty material compared to Auss rivers, ), the prob was solved with more dams which slowed the flow, with that in mind I note that the dirt in your pic is much browner or darker in colour, I am not sure what the above means but it is stuck in my mind, because it will effect " the filterability " of the materials used in the dam/ filter wall, I think the "washed tailings overburben " could be more suitable for dam / filter walls,

:confused:, if you can follow that, haha.

Anyway , that was witten yesterday, and not posted, so I will post it and start another,



kaveman
02:23:36 Thu
Feb 12 2009
Re: Dredging w/Hydraulic Excavator
First thing,...........my ground is going to be fairly clean wash with sand and gravel and lots of large rocks. I expect boulders of several feet diameter to be fairly common. I'm going to take out as much as I can with the hoe and just leave the packed bedrock valleys for the dredge, but my bedrock is highly convoluted and there will be lots of places I can't get into with a 42" bucket. There are boulders in the area approaching car-size and I'm sure we'll see a few. We may have to settle for just rolling them out of the way. I don't mind dredging without visibility, but previous work in this area showed that a large amount of gold was deep down in the bedrock cracks and we'll need to see in order to work the cracks. Here's a pic of the blown bedrock at the river's edge. I expect that the bedrock under the bar will look about the same.



I don't know that the hydraulic elevator will work for us. It's going to be suction nozzles, blaster hoses, air chisels and prybars. Years ago a friend dredged this area and got great gold. He mentioned that he'd done his best blasting with a 2" firehose and cleaning a long bedrock crack with his 8" dredge. He figured he'd done about all he could do, but we'd been working a little harder and getting good gold out of cracks with an air chisel, so he tried the chisel on the 'cleaned' crack the next day. He pulled five more ounces out that day, and never used the dredge other than for diving/chisel air and sucking up the chips. There's no way to really clean these cracks without working underwater.

dredger,.................the nice dark dirt in the background pic used in the diagrams posted above probably doesn't have much gold in it. That pic is from Central Park in New York City. :devil:

I didn't do that to try and fool anyone,.............I was just trying to find an aerial view that I could use as an example that had pretty good resolution, and I figured Central Park probably had the best Google Earth coverage. Central Park was nothing but full tree coverage and baseball diamonds, but I found this one little corner where they'd obviously been tearing up, so that's the spot I used for background. Here's an shot of my actual sticks and stones,......



We're going to keep the site as clean and tidy as we can, but I can't think of a way to get anything done without at least two holes, and three works much better. The gravel plant is already onsite and should be able to handle 20yd/hr+/-. That'll work out to a long three days to run all the material removed from the three holes, depending on exactly how deep we are to bedrock. I'm guessing we'll dig a day or two, dredge for 2-3 days, and process gravel for another three. I think the digging, dredging, and processing will need to be done in separate stages rather than all mixed up. If I have to get into the dive gear, I'd just as soon stay in the dive gear until all the underwater work is done.

I agree that the washed tailing would make the best filter, but I don't think we'll have any washed tailings to work with until after the dredging has started. I will have the hoe sitting there for tailing removal/dam building if it becomes necessary.

I may have posted this one before. It's the only pic I've got of the hoe with some real material in it,..........digging a test hole last year just to feed our curiosity. All we did with that gravel was pan a bit before dragging it back into the pit. Really wet in the spring when this pic was taken. Bone dry later in the summer.





keninla
03:57:28 Thu
Feb 12 2009
Re: Dredging w/Hydraulic Excavator
Kaveman,

It looks to me like dredging will be kind of slow going with all that oversize that you will have to move. ???

If the bedrock is so uneven then I would think that many boulders would be in places that are not easily reached by the excavator.

also, If I remember correctly you are on the Klamath river - right??

Ken


dredger
04:45:28 Thu
Feb 12 2009
Re: Dredging w/Hydraulic Excavator
Hey vortex,

mate, thanks for the good wishes, I have always admired your great stuff, I only wish you would get yourself one of these,:smile:.
,

Save ya back heaps, :devil: Ps, actually i wish everyone with a dredge would get one, :devil:

Hey kaveman,

First , I have a few drawings partly done, ( but I am not happy with them,:confused: , plus i like your pics, plus I have a few things on my mind, and of course not much time, plus I will do a drawing to hopefully explain a concept in concentrating the cons previously mentioned,

I have read today's great posts,

The Grayling are safe in Deadwood. DEC and EPA are happy with how I do things.

I agree with pitchak, 1990 ----, I found the Authorities did not have any problem if the work is carry out " out of the river flow ", which has " no "effect on living things in the river, fish/ micro bacteria /fungi ect,

"I'm expecting Dredger to post some info on filters for the dikes",

Ok, just had an idea on showing /hopefully explaining points of interest ,


1. is the clean water inlet to the hole, I usually start the inlet trench about 6' from the flowing river, then I dig the work hole and tailing's trench ect , then I will build a rock wall " dam "by hand and lay canvas strip to stop most water flow, this backs up and quickly water starts to flow into the inlet trench, I can quickly adjust the water flow into the work hole,
2. is the flowing water entering the hole so as to cause a "swirling action in the hole",
3. is the normal dredging water height,
4. is the normal tailing's dam water height , which also means the tail of the sluices is about 2-3" under water level,
( judging by the shadow it is after lunch and I still had to adjust the flow gate in the river dam, ).and looking at the sluice water height I guess the pumps are warming up , and I am taking the pic), If at any time like every 2-3 days the tailing's dam water level was getting "clogged up " i would idle the dredge , and move the excavator, and "sweep the insides of the tailing's dam/ filter walls, NOT INSIDE THE TRENCH, JUST THE WALLS ABOVE GRAVEL LEVEL, ( couple of feet deep in water,dam walls about 3' high, because all the filtering is done " through the walls" ,
5. is both sides of the sluice header box which are usually over flowing or dribbling water from the work hole into the tailing's dam,
6, is one of 2 Honda 13"s
7, is 2 of the 2 , 4' long stainless foot valves,
8. is opps, the direct of the
outlet of the work hole, ( not really much water exits the hole when the dredge in full run mode, basically the water river water enters the trench, along the trench, and up the nozzle, and that is super clear water,
9. is a green shade cloth to divert floating grass ect off the foot valve area, ( works very well , the dirty water has no real wear characteristics, )
10. is where the work hole dribbles , if it starts to over flow I either adjust the gate in the river dam, or place rocks and strips of canvas and raise the water in the work hole,and stop any over flow, ( the old guy was complaining about his boots getting muddy, )

Please note, it was my intention, fact is , it is my intention to dredge the the tailing's or silt trench next, ( cause I only got half the gold on that bend that time ),

Ok another pic, back asap, dredger,


dredger
07:07:17 Thu
Feb 12 2009
Re: Dredging w/Hydraulic Excavator
hey kaveman,

mate, I was wondering why I was getting a wiff of red socks in Alaska brown dirt,, haha, ( joke),

That's my kinda river gravels, excellent, I hope there is good fall in the river gravels and the bedrock over the length of the ( I suggest ) two holes, perhaps 70-80 feet, in length x say 30 feet wide at the work hole, and x 10 feet for the disturbance from the silt trench and dam/filter walls, do keep the site as small as poss, and I always try to return or rehab to original contours, Actually almost picture perfect contours, but I don't have old large tailing's mounds to process either,

As to the rock bed, I would be like a pig in mud, I would first build pad to work from, then I would slip off my bucket, and on with my ripper tyne, and have a little nudge around the crevices, while pushing the larger rocks to the perimeter of the site, bring a pump and hose to wash the rock and stack them as dam walls around the perimeter of the proposed site, and fill that with water from your auzillary motor/pump, small dredge, and small hydraulic jack hammers running off the excavator, :smile:,

Sorry gotta run, I will the other pics asap, back asap,

kaveman
03:36:07 Fri
Feb 13 2009
Re: Dredging w/Hydraulic Excavator
Yes, that's right, we're on the Klamath. I do expect that there will be plenty of large rocks jammed into the bedrock valleys. It won't be much different than standard river mining except that we'll have the excavator standing by for any heavy lifting and the top several feet of overburden will be gone.. Gotta be easier than winching! Wish I had a ripper, but this year we'll have to get along without it.

Dredger, I'd love to see all the pics you can dig up. We won't have a natural flow of water from the river to fill the holes, but I've got plenty of pump to get it done. Suspect we'll be pumping every morning to refill what seeps out during the night(at least in the spot we intend to start). Up against the hillside(away from the river)we'll have plenty of natural seepage at least in the early part of the season, but that'll wait until next year at the earliest.

dredger
03:57:03 Fri
Feb 13 2009
Re: Dredging w/Hydraulic Excavator
ok, I spoke to a good friend a while ago, who told me about using high pressure cleaners on above type bedrock, i said i would think of a idea and post it, and the idea came last night , ( better late then never, ).

Petrol powered Hy pressure water blaster, and wet dry petrol powered cyclonic type vacuum gravel recovererr.
------------------------------
Very good suction, even a 8 hp 2" suction hose would be very effective, please consider how often you get a blockage in the vacuum cleaner. :devil:,

Next is high view of the work hole,,
-----------------------------
Sorry this pic was to small to add no's,

Next is another view of the dredge running, please note the tailing's hole and work-hole are full, which is the normal operating water height, please note ,the old guy is still standing there, ( bless his cotton socks, ),

testing back with one more, asap.


dredger
04:29:34 Fri
Feb 13 2009
Re: Dredging w/Hydraulic Excavator
Ps, some comment on the pic taken high above the site,

The blackened tree ( right bottom corner of pic ), shows a lightening strike, at which time there was a diver in the water, he stated he was "knocked out " for a short time, but continued dredging,

Hose /sluice motors are clearly visible, A marks or shows inlet trench to hole, B is overflow from hole, please note , just left of C , ( out of the pic, ) there is a large tree on river bed, just this side of the pumps, please note for later reference,,

The 6' x 4' trailer, with a blue drum, carries the engine and pump frame, and the bluy green canvas box is the trailer cover,

Other yellow trailer is for the sluice, both trailers are loaded/ using the excavator as a crane, all machinery can be removed from site in 12 minutes, in times of flash flooding,

Far side of the hose is shallow bed rock , about 4 ' deep overburden, this side of the hose , show a deep gully cut deep into bedrock bottom, 15-20' deep, ( running length ways), ,

dredger
23:30:31 Fri
Feb 13 2009
Re: Dredging w/Hydraulic Excavator
hey kaveman,

"""""""""Dredger, I'd love to see all the pics you can dig up. We won't have a natural flow of water from the river to fill the holes, but I've got plenty of pump to get it done. Suspect we'll be pumping every morning to refill what seeps out during the night(at least in the spot we intend to start). Up against the hillside(away from the river)we'll have plenty of natural seepage at least in the early part of the season, but that'll wait until next year at the earliest.
I have a few more pics, perhaps we should start another thread before these pics get hard to load, ??. dredging wHydraulic Excavator ,PART 2. ????>
nice info in ya post mate, ( AND A GREAT PIC OF YA EXCAVATOR TOO, yAHOO.I hope we see a few dredge/ excavator operations open up on the Klamath, slope/ angle bedrock/ hillside is good, I would also suggest there is "perhaps" a way you might only have to pump say three work holes of water across and up to where you actually want to work, then because you filter that water so well you could recycle the water from canvas lined clean water holding dams ?? level / below /above with your work hole, ??. I would also go further and suggest, it is possible that a dirty water ( not including overburden/gravel / rocks from the sluice, just fresh dirty water, ),, dam wall/filter could be constructed in front or up-hill of the work dredge hole, no worries, and have as little sepage as poss, ???>
This next pic, is really the heart of the filtration dam /filter /wall concept, , i was just getting ready to back fill the tailing dam when I remember to take pics,
,
testing, back asap.



dredger
00:45:39 Sat
Feb 14 2009
Re: Dredging w/Hydraulic Excavator
ok, to let you see how far or long the tailing /filtration wall is please note in this pic,
1, is the motors and pumps,
2, is the foot valve sun-shade green cloth,
4, is where I had already started to drag the wall back into the trench, back filling, I only managed a few yds before I realized i needed to take pics, you can see the shallow trench about a yd deep x a yd wide, just enough material from the trench to pile up the filtration wall,
6, and 8, Please note, all the way along the grassy bank at the waters edge the vegetation is super clean, no sign of built up silt caused by dirty water escaping though the filter wall , also please note, that from what I saw , "most if not all dirty water " was filtered through the lower 1-1 1/2 feet of the dam wall,and flows out of the wall and back into the river flow,super clean that flowing clean water is about 3-4" deep, full length of the wall to the river flow, basically I would suggest the heavier silt materials leaving the sluice stayed and moved along in the lower depths of trench, this of course would block or clog water trying to filter though the " trench"" sides " , only through the upper dam/filter walls,
7, is a silt "plume " (moving down the flow )caused " ( by me stirring some mud well above the site with a shovel,) this is done to show the yellow ( light brown dirty water moving down stream and to compare with no3 area,
3, is the strip of water along the vegetation, 3-4' , please note this strip or area is also as clean as, no silty yellow residue left on the rocks,
5, is the tree I mention is previous post,
2 , is the river rock wall dam built to back the flow up, which supplied water to inlet trench, built by hand, easy,

I have a few more pics and suggestions on rehab, and the benefits in keeping the area of disturbance to a minimum, this is a very good thing, environmentally speaking, No EIS, required, and only minimum enviro BONDS,

sorry gotta run,back asap. dredger,

dredger
01:38:30 Tue
Feb 17 2009
Re: Dredging w/Hydraulic Excavator
hey kaveman,

Sorry been bussy as, and computer probs, too, still too slow, ( like me ) ,I will start a new thread, for more pics, asap.

kaveman
04:32:11 Mon
Dec 14 2009
Re: Dredging w/Hydraulic Excavator
vortxrex makes mention of a fabric curtain used by TrevNZ. I rmember seeing the picture Trev posted, but evidently I didn't save it and can't find it with a search. Any chance anyone has the pic saved? I think the curtain might be an all around better deal than leaving dikes beween the ponds.

Jim, if you could work your search magic, I'm pretty sure it was posted in one of Trev's suitcase dredge threads.

Greg_in_BC
17:23:40 Mon
Dec 14 2009
Re: Dredging w/Hydraulic Excavator
Love the discussion gents!

The material that I remember Trev referring to is the ground fabric used for landscaping. Has small holes in it so the water can get through but is slowed down. I think a couple curtains would slow things down a lot as the water flow/pressure between them would be reduced.

Might need to use a pressure wand now and then to wash the slime off the upstream side and open up the pores again.

dredger
01:25:38 Fri
Dec 18 2009
Re: Dredging w/Hydraulic Excavator
Love the discussion gents!
Me too. but my computer is stuffed , I plan a new one and camera asap, too bussy with immediate project,
Merry Christmas and Happy New Year to all..

More blar blar, for the new guys, http://bb.bbboy.net/alaskagoldforum-viewthread?forum=2&thread=506&postnum=60.

back asap, dredger.

kaveman
04:26:27 Fri
Dec 18 2009
Re: Dredging w/Hydraulic Excavator
In case anyone's interested, I went with a two pronged approach on the fabric silt dam,...........

Primary fabric is going to be a woven poly tarp. Two 20'x20' tarps are on the way. Basically going to weight the bottom grommets and throw them over a line and tie them in with zip ties. Should give me a double thickness of about 70% shade and make a wall 40' long by 10' high. You can probably see the tarps her, at least for awhile,.......
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330348961469&ssPageName=STRK:MEWNX:IT

The weed control fabric looked a little frail for continuous use(actually, it looked a lot frail), but would probably be a better bet for a single and simple setup in a dredging operation. Cheaper and easier to handle(maybe?). Problem is the sizes available. I bought this roll for backup to the tarps,........
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=330383086085&ssPageName=STRK:MEWNX:IT
If need be, I will stitch it in between the double layer of poly and get near 100% filtration. It'll be more cumbersome to store and handle, but it should get strength and protection from the poly tarp. I don't expect I'll need it, but I'll have it available if I do. I'll use it for weed control around the trees I plant for reclamation if nothing else.

This was the only roll I could find at 4' width. Most everything else is 3' and more lightly built. 12.5' rolls are available on ebay, but were around 450' long and $450,....................way more than needed. I almost went with this stuff which is probably perfect, but the tarps doubled my layers and were just a bit cheaper and had the advantage of easy setup being simply draped over a line,...................
http://www.growerssupply.com/farm/supplies/prod1;gs1_shade_houses_shade_cloth-gs1_sunblocker_bulk_shade_cloth_1;pg107761.html

I've used this shadecloth in 80% for canopy over the dredge, and it's the same stuff they use for tarping over loaded trucks. Very tough and it doesn't unravel.

More I think about it, the more I like getting away from the dikes and just using the silt curtain,............assuming it works! Can't see how the dikes could be less than ten feet thick without posing a collapse hazzard and sooner or later they'd need to be removed and dredged to clean the bedrock below and that process would be silted out for sure. At least the curtain doesn't cover any ground and can be easily moved from place to place. Hopefully.

Greg_in_BC
16:12:33 Fri
Dec 18 2009
Re: Dredging w/Hydraulic Excavator
Kaveman, there is a more commercial material that is used for road construction etc up here - especially on soft ground to keep the road bed stable. It is like the lightweight landscape fabric but much heavier and can be found in very large rolls and sizes.

It is referred to generally as geotech fabric and there are many varieties. Check out a simple search Geotech fabric and you migt find something in your area.

It is also used by enviro guys for slope stability control, and drainage control to keep from scouring areas and slow the flow.

If you contact some road builder or construction they may have some end pieces to get rid of?

Good luck in your search and looking forward to see your operation progress.

I like the idea of working the hole forward and using the curtains. As you say the other way you would have to come back and work the dikes left behind (plus some of the tails (how long for them to stabilize?) to get the remainder of the bedrock.

Added: just noticed that this company list the water flow through rate in GPM/ sq ft. and they actually list a
turbidity/silt curtain

You might be on the right track with different permeability levels as you go from the high solids content side to the working side. Larger to smaller. Kind of like a screen plant works better if you screen down progressively. Each curtain will have less solids to deal with and less water pressure flow through. Might have to brush them off or water wand them off now and then to open the pores again.


kaveman
17:12:35 Fri
Dec 18 2009
Re: Dredging w/Hydraulic Excavator
Thanks for the links Greg. I found the silt fence on ebay, but all rolls were either 2' or 3' max height. I'll bet the 12.5' roll I found was for roadbed, but that was the roll that came in a 450' length. I think it came up in a search for landscape fabric. I'd have been happy to pay $1/ft for the 30-40' I think I might need, but 450' was a little too much. Coulda still put it down under the gravel in the drive that I'll probably be trucking in next spring tho,................

That stuff shows a flow rate of roughly 4gal/min/sq', and the tarps I'm using if anything will be more porous, so my curtain should start off well over 1200gpm. That's not counting any of the natural seepage coming in from the sides. Probably will have to de-slime the thing from time to time, but I think it's all a'gonna work.

The dredge will likely be discharging tails away from the curtain, so all it should have to deal with is the suspended silt. I'm used to dredging in the Klamath, which might have 10' visibility on a good day. I won't be surprised if the ponds run better than that.



Greg_in_BC
04:57:26 Sat
Dec 19 2009
Re: Dredging w/Hydraulic Excavator
Kaveman, I wonder if you will need to have the entire curtain area to allow flow through water. You may have enough flow back by only allowing a smaller portion to flow back. That would allow the water to settle more in the rest of the pond area.

You could even have the exposed flow through areas offset from each other (separate the curtains with a foot or so to allow settling as well?) so the water has to move back and forth or ??

Lots of options for experimenting with, will definitely be interested to see what works and adjust for best results.

I know what you mean about the Klamath, we had near zero vis with a current sand storm in 40' of water in '90. Tough working. Dredging by brail and constantly checking for 'hangers'.

cash2u
20:40:30 Sat
Dec 19 2009
Re: Dredging w/Hydraulic Excavator
You might consider what we do: get or build an oversize bucket and cut holes in it just smaller than the suction nozzle on your dredge. Only dig what you cannot use. the fewer times you handle the material the more you make. To get started you really do not need to see to dredge what is left. We use bails of straw to clean the water when necessary.

kaveman
00:29:11 Tue
May 4 2010
Re: Dredging w/Hydraulic Excavator
Just bringing this one back up to the top so it doesn't slip off into the archives where I can't get to it. If I can find a little time, I'll update it. Suffice to say that the dredging portion of the operation was a no-go. We were completely mudded out. The silt fence didn't work, but by the time we got the hole dug and got a look at the water in it, I wasn't surprised. Visibility was absolute zero. Zero,.............as in you couldn't see your orange glove no matter how hard you pressed it against your facemask. Dredging blind is one thing, but in pitch blackness it's a whole 'nother story. Once you got below a 6" depth there was no light a'tall.

Even after letting the hole sit for two weeks, it didn't improve. We did throw the dredge in and have a go, but the bottom was covered with a 6" layer of clay and the dredge didn't much care for that. Once you punched thru it with the nozzle, you could literally peel it back and roll it up. Even when you got thru to gravel, you couldn't maintain orientation and if you took your hand out of the hole for more than a few seconds, it would drift over with new fallen silt and you'd lose track of where it was. Other than that,......................it was also cold. A total nightmare. Reconfiguring the operation to exclude the diving portion, but we're still going to need some type of suction device, probably manuevered with the excavator more or less blindly.

I think I need dredger to post a detailed write-up of his nugget sucker. Looking at rippers for the exc and maybe sticking some sort of suction tube in behind it along with a blasting nozzle or two.

dredger
12:12:43 Tue
May 4 2010
Re: Dredging w/Hydraulic Excavator
No worries kaveman, I have been trying to get back to this thread for ages, and I did know it was , about 5-6 pages back,

I have been doing alot of contemplating on fluidizing the smaller size cons, plenty of ideas, will post that here on this thread.asap,

Sorry guys, I have only just noticed last few posts, was that last x-mass or the one before, :confused:. some good ideas there,

Well, kaveman, we will have to work out what went wrong, but quickly looking at your post, I am a little worried the new guys might be getting confused, my dredging with a excavator was carried out in the current river gravels, and your operations were carried out on a high bench above your current river, which really should not have made that much difference, ??. so I don't see the prob is there.
Your silt fence sounds ? well it did not work, so could you please explain it construction and concept,
I have ? 4 more pics of my operation, showing clean work hole water, and dirty tailings water , I just putting arrows and directions on them before posting,asap.
Your description of work in the dark , been there done that, and liked it about as much as you did, haha, atleast we can laugh now, we survived haha.
One thought is ya comments on "probably manuevered with the excavator more or less blindly. ". I know what you mean about loosing track of where you are working, under water seems to increase loss of orientation, how ever when sitting in a excavator and feeling around with a bucket or sucker nozzle is much less of a problem of orientation, ( with practice ) you will get to know what the bed rock bottom of the hole looks like before ya start a dive, in clean water,

You wrote, " I think I need dredger to post a detailed write-up of his nugget sucker. Looking at rippers for the exc and maybe sticking some sort of suction tube in behind it along with a blasting nozzle or two ". what ever you need, no worries, a thought here is we need to know what you intend on running or powering which concept, sucker /blaster /s , and I was hoping you are able to do simple sketches on your computer, ??. hopefully you will be able to show how and where your hole and silt fences were set up,
Another thought is you may have to make application to remove a or a few truck loads of fine river gravels from the river, to use as a water filter medium,up on ya high bench, please note, I think those particular fine river gravels I use to filter water clean , you would not really find in a high bank deposit, that had already been dug by the old timers,

Out of time , but I am still sure you can dredge in clean clear water, if you can supply / recycle as much clean clear water as your sucking out, it can be done, and we will have to talk more, just rearrange the site, no worries,
On the up side , I know pitch black cold water is colder then clean clear sunlight water with 40' advisability, mate, please remember cold water is your friend, helps hide the pain in ya muscles, haha, and when ya dredging in clear water, the cold water helps ya work faster, haha,

back asap.dredger.

kaveman
03:50:20 Sat
May 8 2010
Re: Dredging w/Hydraulic Excavator


Kinda makes you want to jump right in and spend the day under water,.....................doesn't it?

The dredge is an 8" subsurface that's been modified to feed from two 6" hoses w/nozzles. That's not the Loch Ness Monster; we had to float the hoses just so we could find the nozzles. Also helped immensely when it came time to clear the plug-ups in the hose. Unless you could lift the hose above the water surface, you couldn't see it. For the little bit of gravel we moved, we seemed to have a bunch of trouble with plugs. Suppose it was the 6" slugs of heavy clay going up the nozzles.

The discharge end of the dredge was bolted to the line running across the pond that the curtain was suspended from and the tailing went directly to the rear side of the pond. Whether the curtain had any effect I couldn't really say as there was zero visibility on both sides of it from start to finish. At any rate, it didn't seem to 'clean' the water any, although it may have been somewhat effective in preventing it from getting any worse(had that been possible). The curtain itself was a double layer of open weave poly tarp similar to shade fabric found here,......... http://www.gemplers.com/shade-cloth ,.................probably up around the 80-90% range. We had some of this stuff http://www.gemplers.com/product/139480/3-oz-Black-4-ft-x-300-ft-Non-woven-Spunbound-DeWitt-Weed-Fabric available to sandwich in between the poly tarps if needed, but we never got around to trying it. May have helped, but it would have been next to impossible to have added it once the tarps were stretched across the pond and removing and reinstalling the tarps would have been a four-day effort. We gave up on the diving.

Oh, BTW, we're not up on a bench,..............we're just on the bar maybe ten feet above the river but several hundred yards(meters)away from it.

I've been discussing our problems with everyone I come into contact with and one idea came from a friend who says he's had similar problems with dozed stock tanks down in Texas. Evidently the clay soil down there silts up the water in the cattle ponds in a similar way and it'll stand for weeks or months without clearing up. What they do is add lime to the water and it causes the silt to settle out in a day. Supposedly the water's slightly acidic which causes the silt particles to take on a weak positive charge that keeps them suspended(or so he believes). What they'll do is take two murky samples of water in clear glass jars and add a bit of gypsum or crushed lime to one of them and that one will be clear come next morning. Certainly might be worth experimenting with. If we can get the water cleared up initially, we might be able to come up with a system that'll keep it clear enough. It's the initial digging of the hole underwater that stirs up the silt in the first place. If we can knock it down just once, we may be able to keep it down.

We won't be out there again until late summer, so by then we'll be facing an entirely different situation. The hole will still be there, but the water will all be gone. I suspect the gravels will be safely tucked away under several inches of hardened clay. We'll get down in the hole with the digger and see how deep we can get working between the convolutions in the bedrock. I could feel the bucket skipping from crest to crest at the bottom of the pond, but without being able to see anything I wasn't having much luck getting down. Should make some headway once it's dry. 42" bucket is still going to be restricted from the narrower valleys, but if we can fabricate some sort of ripper tooth we should be able to at least loosen it up for excavating by hand. The ripper may also come in handy if we're still working this spot again in the spring when we'll be back to a full pond. That's where the ripper/sucker nozzle may be needed. I would expect to run maybe a 6" nozzle pumping directly to a 6" surface dredge floating in the pond,...................unless the water clarifying experiment is successful in which case we'll try diving again. Either dive with visibility and clean the bedrock with a dredge or rip the snot out of it from the cab of the digger in the blind. Those seem to be the only options.

Other stuff didn't work too well either, but we did have a few successes. Maybe get a chance to talk about some of those things over the weekend. Joe_S_Indy isn't going to be too surprised with what went wrong,...................his advice re: the washplant were spot on.

kaveman
00:43:13 Sun
May 9 2010
Re: Dredging w/Hydraulic Excavator
From the archives,...............the shaker plant.

http://bb.bbboy.net/alaskagoldforum-viewthread?forum=50413641711&thread=6487

As predicted by many, we did have trouble with the plant. Once we got new belts installed and all the pulleys lined up, it ran fine. We had plenty of water for the sluice, even using the smaller than planned P350 pump. We do need new spraybars over the screens, but the gravel washed well enough even without a good spray. The screen was running a little shallow, but still shed the gravel easily at the small volumes we were able to run. The sluice may have been a little steep, so by jacking the tongue of the trailer we can improve both the screen and sluice slope(steeper screen and shallower sluice since the angle between the two in not adjustable). A single layer of 3/8" moss in the sluice left a few riffles floating above the carpet so we'll double up next run or place another layer of padding beneath the moss to close up the gaps. We were disappointed with the quantity of gold recovered, but still believe the recovery system itself is working well. We saved some unbelievably fine gold,.................there just didn't seem to be enough of it in the ore.

The big downer turned out to be the grizzly. Like Joe suggested, it flat did not work. As we feared, the slope was too shallow and the rocks jammed in the spaces at the crossmembers. Not surprised at that outcome, but it did rock up much faster than I had thought it would,..............as in 'instantly'. First bucket simply sat there and we had to shut down and shovel the load off the top. We only had a few days left to work so we had to come up with some fixes quick. I'll get some time in the next couple of days to explain what we did and show some pics/vids, but I just found the link to the washplant critique and wanted to get it posted up real quick for review. Need to get some sleep before I drop. More later.

dredger
03:04:05 Sun
May 9 2010
Re: Dredging w/Hydraulic Excavator
Ok, Just noticed your posts, just finished this post, sleep tight,

I am Not trying to convince ya to dredge, only relate to how ya can dredge,and or a wash plant , and basically both. these will be hard and fast, not to hurt , but to help i hope,

FIRST 3 reliant factors,
1, anyone at your stage, excav / dredge. please note, the jump to super sucker bucket /blaster , cost money, mostly do it your self,but still cost money.
2,as you require, " sucker nozzle " cheap to build, then and buy a standard ripper Tyne, ( don't forget the cost of a quick hitch or quick change ), and using your current dredge very low cost, and rip /suck the work hole water clean with the nozzle on the excavator, before the diver jumps in just to do the crevices, ??. This method reduces the time, the diver dives, 6 " subby should have enough grunt to get a workable result, ( when i fitted a sucker nozzle I found the nozzle could supply alot more gravels into the box then the box could possibly handle, so I had a dredge hand stand and give me instructions as to how much materials was in the box, over loading was a big prob, and really you can only move a sucker nozzle around the work hole slowly ,
3, rearrange your hole / filter method at very low cost, also slightly modify the dredge, ( remove pontoons and and design / make a canvas "seal for the hose " and dredge in clean clear water as previously pictured , please note the water will not feel so cold when you can see as clear as day, got some dias nearly ready, please consider, we/you " what ever " blew it this time, so don't feel bad you can hit and clean a hole, 1 to 4 days per hole,, depending on how hard it is to chisels the gold out of the crevices, ect, my line of thought is 1 -2 weeks ya gotta cover the cost to date, if you can not do that , I would wonder if you are in ground with gold, or more to the point ,??. enough gold, ??.
4, is urgent , please monitor , if the water in the hole, causes turbidity in the river up to and well after the hole dries out, please take pics too, could be evidence required at a later date, reason for my concern is mainly for operations who continually pump clean water " up " to high operations, , as I experienced in Tasmania,where a operation excav / trommel had worked 2 weeks with such success that the operators took a weeks holiday to celebrate, 3 days into that holiday, they received an alert that the EPA, and WATER RESOURCES wanted to fine them, for silting the river, as I remember the soil was a different colour, but it was fine, and would carry silt for a mile, to fix that , it needed more dams and the dams where lined with or the walls were lined with light canvas,
5, is suggestion you have the line of thought that you won't spend more money up-dating, just get gold the way you thought you where gonna get it, pay for all up to date, and maybe get enough to pay for updates,for next time,

Anyway , gotta run,

Here is a pic of the dredge site, ( in river gravels, ) I suggest it will be easy for you to do same, dias following,

comments on arrows coming, asap;


Did you or can you pump the water to the hole, ??.


kaveman
14:46:18 Sun
May 9 2010
Re: Dredging w/Hydraulic Excavator
We didn't pump any water to the hole. That's all ground water at this time of year. As the hole is being dug, water's seeping in and filling it. We also didn't pump any water out of the hole other than what's spraying into the washplant. Most of that water discharges directly back into the hole, although we had small ponds and puddles everywhere within 50' or so of the plant. That would all be soaked in by next morning. NO runoff and no chance of anything getting near the river. Not worried about that part of the operation.

I'd still like to dredge it and we're not giving up on that just yet. The situation 'seems' to be this,......................there's good gold in this hole, but it's almost entirely below the 7 foot level. At 6 feet, we start hitting the crests of bedrock, so almost all the gold is lying in the 'valleys' where we have a real hard time digging it out. The bedrock itself does not dig,................it's hard as flint. Best we can do is dig all the overburden away(which is where we stand right now)and our gold is lying at the bottom of a pond(winter/spring)or the bottom of a dry pit(summer/fall).

This is vacation fun for us, so we fully expect to spend $5000 each and every time we go out, usually a month in the spring and a month in late summer/early autumn. Sure it would be nice to have the money(gold)coming in instead of going out, but there's enough to make steady improvements and investments if we take it slow. I can easily see a ripper/sucker/dredger outfit running $10,000 and I too would like to be 100% sure of what's in the hole before dropping that much more into it so we're probably going to find something workable for far less investment for now. I'm thinking dry digging in the fall(maybe with the addition of a single ripper shank attached to the bucket somehow)and dry screening into the back of the dump truck; then hauling the load to the plant that will be set up within reach of, but out of the way of, both the river and the digging operation.

All advice and suggestions are eagerly accepted and appreciated. We take criticism well. The only real problem that we face is that all this stuff is taking place 2000 miles from where we live, so our time on station is severely limited. We build stuff and we make changes, but things happen slowly. Occasionally we get to dig a little. Best we can do for now.

Dredging may be off the table until next year when the water's back. It would be possible to try again in the fall, but that would require constant pumping from the river and an additional $1000 worth of new hose purchase. I think it best to plan a dry operation for now and hit the dredging again in the spring. We've got about three months to come up with a new plan.

kaveman
15:41:33 Sun
May 9 2010
Re: Dredging w/Hydraulic Excavator
OK, without going over a whole lot of old ground,..................the dredging of the bedrock didn't work and wasn't going to be made to work in the time we had left, so we wanted to get a look at what was in the bottom layer of gravels while we could. Only thing we had was the untested shaker plant and about a week of remaining time. Just fitting up the sluice carpets, the last of the water lines, and new belts took a couple of days. Once we had everything running and got the first bucket of clay/rock/gravel sent up to the plant, this is what we had,....................

Grizzly Video http://www.youtube.com/watch?v=v0gvv7rV5YI





Failure,............big time. The grizzly wasn't going to work. It wasn't steep enough and even with the 4 water nozzles blasting the top nothing was moving. Large rocks just sat there and 3-4" rocks clogged the openings. Our day was done so we retreated to camp and spent the evening thinking about it.

Long story short,....................we had to totally change it and decided to abandon the entire grizzly and replace it with heavy shaker screen solidly mounted but pitched up at about 40 degrees. We'd previously built up a stationary screen that worked reliably at about 35 degrees pitch but figured the extra few degrees would be a safer bet.



We took the next day off and ran into town for materials. Found a nice piece of heavy screen 5'x5' square made of 1/2 inch wire on three inch centers. Screening to 2-1/2" seemed about perfect for feeding over the shaker. Framing would all be done with 2"x2" square tube. 5'x5' at a 40 degree angle would be a fairly small target for a 42" excavator bucket, but it was the largest we had available and we figured to expand it somewhat by affixing wings onto the back and sides using salvaged plates from the original grizzly. Well,....................that was the plan on Monday anyway.

Tuesday started off with heavy rain and it wasn't until the afternoon before we got a break and managed to get down to the bar to look at the plant and see how much work it was going to be to cut the old grizzly off and get the new screen rigged up. We knew instantly that we were looking at a good week's worth of work and we only had a few days left before we needed to get packing up to leave, so we decided to put that project on hold and try something stupid for a change(yeah, right!).

Since the main object was to run SOME gravel NOW and we were going to dig that gravel from the pond(couldn't use the stationary trailer mounted screen pictured above for wet gravel), and the new screen wasn't going to be ready in time,..........we needed a quick project that could be completed in a day and MIGHT work.

Actually, I'd have maybe had to bet against it working, but I'd have lost that bet. This is what we came up with,......



Video here,..... http://www.youtube.com/watch?v=Rybf0dgB9ig

We knew that even if it worked it was going to be slow, and it is, but with a little practice and better layout of the mining operation I think I could feed the plant as fast as it's able to process material. As it was, we only managed to run about 15yds in 5 hours due to the plant being too close to the excavator, the pump and water lines being in the way, and generally being boxed in with trees, the pond, and all the rock piled up around. I think a steady feed rate of 10-15yd/hr could be achieved with better planning and that's all the sluice can handle.

Anyway, we had to modify the old grizzly slightly to accept the bucket-screened gravel, but here's how everything worked once we got going,........




Digging/Screening Vid http://www.youtube.com/watch?v=aEm04od0e0w

Feeding Plant Vid http://www.youtube.com/watch?v=NQsxz-rTbvo

Digging, screening, feeding got better with a little practice(these vids were shot early in the learning stages). Few notes:

A few oversize rocks still get into the bucket over the top of the bucket screen where it pivots, but that will be an easy fix. The shaker plant has been able to handle these few rocks OK.

One advantage is that the oversize rocks can be dumped anywhere you want them rather than right up alongside the shaker plant where the grizzly would shed them.

Even though it looks like you'd be losing undersize from the bucket when dumping the oversize, that doesn't seem to happen. Might be the wet material or maybe all the clay in it, but the oversize slides right off the screen and the undersize sticks right in the back of the bucket.

The feed is kinda touchy since the screen is free-swinging and the material is wet(occasionally it sticks and dumps out in a heap), but one of the changes necessary to get the feed up to 15yds/hr would be to include a feed tray above the shaker where an entire bucket could be dumped and washed without needing to take the time to jiggle it in bit by bit.

All in all, it worked exactly as we had hoped(and far better than we expected). It took one day to run back into town for the materials(didn't want to sacrifice the 5'x5' screen for the grizzly replacement and decided to go with heavier .250" wall 2x2 framing and it turned out that the day would have been lost to rain anyway)and another day to build it up and fit it to the bucket. Total cost of materials was $105(REALLY NICE SCREEN from the scrapyard,............CHEAP!).

We initially worried that it might not be sturdy enough, but after seeing it built and in place, it's going to be fine and it'll move a bunch of material before it'll show any sign of wear. We actually came up with the idea while standing in the rain thinking about cutting off the old grizzly. Design changed several times during the two-hour drive to the scrapyard and advanced from a fixed screen requiring all sorts of welded or bolted in support to the simple swinging screen we ended up with by the time we got there. It was welded up in camp(laid it out in the bucket with 2x4 scrap and a measuring tape)and fit like a glove when assembled. All we had to do was drill two 3/4" holes through the thin part of the bucket sides for the pivot pins.

Never had a project go from hairbrained idea to working example, all designed on the fly,...............in under 48 hours. I don't know that we'll use it much due to the limitations on capacity, but it's nice to have. It didn't show us much gold because the bucket still can't get down into the bedrock valleys, but at least we felt like we didn't waste our last few days. We got SOMETHING accomplished! We got to run a bit of gravel over the washplant(enough to cleanup, anyway). We got to put a few hours on the plant and see how it was going to work and see what further changes were going to be needed. We had a little fun.

Actually, the thrown-together cleanup sluice didn't work too badly. I'll post it here. http://bb.bbboy.net/alaskagoldforum-viewthread?forum=2&thread=796






dredger
06:51:31 Mon
May 10 2010
Re: Dredging w/Hydraulic Excavator
Yellow arrow , far left side shows blue tarp over flow for work hole, please note, water level in dredge hole is down a few inches,

Other yellow arrow shows water level in work hole down a few inches,

White arrow shows water level down at the jet a few inches,

Pink arrow shows the hoses can be easerly seen in the clear water,

Black arrows on right show low water level in tailings dam,

Red arrow shows red Honda 13 hp, ( x 2 ).

Black arrow under red arrow shows working water level on pump frame in tailings dam, please note the distance between the tailings dam wall and across to the river,





dredger
08:04:40 Mon
May 10 2010
Re: Dredging w/Hydraulic Excavator
WOW, alot of work kaveman.

So the first thing that comes to mind, you will get more confident and faster with more practice, no worries about that, fact of life, another fact is from my years of experience and passion about excavators, , I can tell you have got the right moves, few more tricks to learn, bit more throttle, and you will be as smooth as a babies back side,

Second is a thought about "a " method that is and appears very efficient, but wastes a lot of time being efficient , so, my line of thought is focused on your sluice, and suggest the sluice is the problem in so much that is " not " processing gravel all the time you are operating the excavator,, so please note in ya video's , ( great videos too.) that when the bucket is feeding the hopper, " sluice is processing the gravel, roughly 30 seconds,that the sluice is actually sluicing gold, then " waits " 60 secs for the bucket to get bigger rocks off the screen in the bucket ,and feed the screen and another 30 secs to acutely get the bucket filled, so the sluice is waiting 60 secs plus 7 secs for the bucket to return from the screen back to the hole, 97 secs in total,and the sluice is only working 30 secs of that time, 67 secs sluicing time wasted, more then 2/3 time wasted,

On the other hand if you were feeding the sluice with a constant feed you would process 2 times more gravels , in the same time, every hour you could be cut in half, to 30 minutes, and do twice as much in one day, generally speaking,

Solution, reinvent the hopper , to handle a full bucket of gravels that are just dumped in while gently laying the load across the screen, , a hopper that can handle a full bucket being gently and quickly dumped in it, with plenty of grunt to shake big rocks while being blasted with jets, ( please note the concept is to "leave the over size rocks on the screen being washed and shaking for the full 30 secs, until the next bucket load " brushes " ( side ways push ) to the , " left " off the screen onto a chute where they will slid on there own, then and at that time the bucket has stopped ready to dump the next lot of materials in the , across spread over the screen, giving those gravels a full 30 secs of shaking and washing, also enough storage area under the hopper screen for a bucket full of screened gravels, and orga / feed those screened gravels into your shaking screen / sluice in just under 30secs, ??.

Please note an interesting point here is without changing your original processing plant, but removing your grizzly , and redesigning it, to discharge out of a chute, over the sluice tailings, you will be able to load the hopper , and push or pull the vibrating screens tailing /rocks,to clear the rocks that have built up under the conveyor,
And clear ( or back fill the hole ), the over grizzly size washed rocks that have fallen on top of the sluice tailings, at the opposite end of the unit / conveyor belt, with tracking around to clear the oversize off the grizzly,

Please note in this Arch Cannon operation that the excavator removes / digs a bucket of pay dirt, and gets it to the plant in a smooth motions of the bucket, 15 secs, i suggest to dump and return under 15 secs, total 30 secs or under,



1,is the direction the bucket brushes the the washed shaken rocks to the left,
2, is the level the bucket enters the hopper,
3, is the chute that drops the rocks onto the fines sluice box,
4, is counter balanced weights spinning to vibrate the hopper, ( big time, ) as well as red springs that the whole hopper is sprung, high pressure jets not shown,
5, is storage area for under size ,
6, is adj hyd ORGA screw to feed your screen, constant controllable feed,
7, is 13 hp Honda drive hyd pump, ( hoses note shown, ).

I would suggest that the shaking screen not be attached to your trailer, instead it be sled mounted , and separate, ( might deliver too much vibration to the sluice,

A poss scenario, you have dug as much of the hole within its reach , so the excavator is moved forward a few yards, in the same direction as the trailer is pointing, any build up from the conveyor is " pushed away " and a chain is used to pull the trailer over where the conveyor had dropped rocks,a few yards forward,the excavator is then chained to the front high side of the hopper , and pulls the shaking hopper over your trailer again, to line up the orga , and your small hopper on your vibrating screen then the excavator reaches around to where the oversize and sluice tailing are piled and pulls them back into the hole for easy back filling the hole, then the excavator slews around and starts digging again, 30 secs per bucket, or 120 buckets per hour, only stopping to drag / pull the trailer and shaking screen a few yards,

just trying to help;

Back asap. dredger.

Ps, I suggest that concept would work well if the hole was dry, :devil:

kaveman
17:08:23 Mon
May 10 2010
Re: Dredging w/Hydraulic Excavator
Wow dredger,......................you're putting more thought and effort into this than we are. Yeah, the de-rocker and feeder would be ideal. Frankly, I doubt this little pieced together shaker plant is worth all the effort, but some of the ideas are doable. I never considered it to be anything other than a test-plant and we have no hesitation when it comes to changing things around. I understand that the sluice is sitting there running nothing but muddy water most of the time, but that's how it worked out this trip. We had actually planned to run full buckets across it, but the size of the sluice mandated that we hold the rate to one bucket-load every 2-3 minutes. The plan was to meter the bucket-load in for the first 2 minutes at a rate the plant could handle and then dump the final bit; letting the water chew on that for 30 seconds while the excavator digs another bucket. That's what we would have done had the grizzly worked. Plans are nice to have. They give you something to talk about until everything goes wrong.

I don't think we're up to the task of engineering and building all that apparatus, but a simple stationary feedpan might work well enough. Just an inclined hopper that can take the full load of the bucket where the blasting nozzles can work on it. The material( this material at this spot)washes very easily and is pretty clean by the time it hits the screens. The screens size it, but don't have to clean it. Thinking about having at least one of the blasting nozzles controllable from the ground so a man can even out the feed a little. Being able to free up the excavator and keep it moving would be a huge improvement, especially now that the digging is so slow.

I don't claim to be much of an operator yet, but it's hard to be smooth the way we had this operation set up. The excavator was so close to the plant that I had to bring the stick all the way in to the stops and then boom all the way up to the stops to keep from hitting it when raising the bucket. Undo that to lower the bucket. Dumping the oversize off the bucket screen required that the boom be lowered and the stick all the way out to clear our waterlines. I was reaching out into the pond as far as I could for each load. Stop to stop,........stop to stop,........stop to stop,....................not a very efficient way to dig. It got pretty ugly a few times and I can assure you that I have vids that show that I really am not very good. But I'm smart enough not to post the really ugly stuff. Suffice to say that the plant got inadvertently 'modified' a few times during the day.

What you can't see in the vids is the stacked rock to the left and the trees to the rear along with all the tools and crap we have scattered around the worksite. It was like trying to work in a cluttered closet all day. Well,...............at least nobody got hurt. We had a good day.

I have a few simple ideas for regulating the flow of material through the plant. Mostly just making a couple of spots that will hold stuff back until the flowing water can work it out. The only visual cue I get from the cockpit that tells when there's too much feed or too little is the conveyor. I can see when it's running full or empty, but that's about thirty seconds downstream from what I'm doing with the bucket so it's not much help. Better would be a camera looking up from the discharge end of the shaker screen. If I can keep a steady load on the screen, I can probably run the plant at capacity and maybe multiply our throughput by 7-8x. Unless we get deeper in the hole, we'll still be going broke at that rate tho. We haven't seen anything other than flood gold in the stuff we've processed so far. The test pit that this hole is built around showed much heavier gold than we're seeing and as for quantity,....................1/10yd from the testhole had more in it than the 15yd we just ran. My math says we should improve by 150x eventually.

dredger
05:45:45 Sat
May 15 2010
Re: Dredging w/Hydraulic Excavator
Sorry kaveman, bussy as, back asap. sorry . phill.

billcosta_rica
20:05:52 Sat
May 15 2010
Re: Dredging w/Hydraulic Excavator
kaveman
check this video out http://www.hollowaybar.com/videos/hb15.html
and there are a few more... food for thought.

bill-cr

kaveman
15:04:54 Sun
May 16 2010
Re: Dredging w/Hydraulic Excavator
Thanks for the link bill. I spent most of last night checking out the vids. That feedpan is very much like what I'm thinking. He used the bed from an old dump truck and it seems to do the trick.

dredger
23:05:22 Sun
May 16 2010
Re: Dredging w/Hydraulic Excavator
Thanks Bill, that is certainly my kind of digging, " fast Forward ". :smile:.

Hey Kaveman,

Great video, Aye, I liked the dozer spreading the tailings, but , dozers cost money, so a thought for your consideration, could be to make your processing unit " mobile " , I would suggest you check out how cheap you can buy complete hyd excavator track and base units , you just remove ya trailer wheels /axles, and attach / weld the complete track / and track frame on to ya trailer, only small ones, maybe 3 -5 ton track bases, fit small hyd pump to your screen engine, and pipe it to the tracks,

Your conveyor belt, would be very handy then, " scenario " by just touching a control stick mounted near your hopper, with your bucket, the mobile unit tracks would move the unit and conveyor belt to spread the tailing around where you like, and also be close or the right distance for loading,


You say " That feed pan is very much like what I'm thinking. He used the bed from an old dump truck and it seems to do the trick ". I agree, and suggest you set up water jets so that are directed " up " to the gravels, you have just dumped, that way the gravels are blasted and roll or move down the angle, which does not stop or fluctuate the flow of water into the screen, if you try to blast or push gravel down the hopper, you stop the water flow,intermittently, until it builds up and flows over the gravels you just dumped, and causes major floods on and over the screen, and or down and out of the hopper,

Back asap;

dredger
23:21:12 Sun
May 23 2010
Re: Dredging w/Hydraulic Excavator
Sorry kaveman,

Sorry again, I am really out of control. bussy ,please accept my apology, I will be back asap. dredger.

kaveman
00:29:28 Mon
May 24 2010
Re: Dredging w/Hydraulic Excavator
Ahh, no rush at all. Looks like nothing's going to happen until September at the earliest. So far, all I've done is corral a couple of ripper shanks off a Cat dozer. Missed a great deal on a 24" bucket that could have been modified for my machine relatively easily,..............but I hesitated since it was 2000 miles away. I coulda shoulda bought it. Might still get another chance at it as it didn't sell but it also hasn't been relisted yet.

Yes, spray from below in the feedpan for sure. Let the water spray do the work and regulate the flow of material to the screen/sluice, just like in this operation,................. http://bb.bbboy.net/alaskagoldforum-viewthread?forum=2&thread=44

Also similar to the cleanup sluice we set up,.... http://bb.bbboy.net/alaskagoldforum-viewthread?forum=2&thread=796

dredger
00:41:41 Thu
May 27 2010
Re: Dredging w/Hydraulic Excavator
Sorry , been busy as , and still am, but got a few mins,

I have some interesting points or clues,about the link and the , that are killing me to share with new guys,

First , I hope finnishdigger takes no offence at or from my blar, blar, cause i do not mean any offense and my heart bleeds for him waiting, to hear from the Government, and I wonder if the Government is banning dredging just in Natioal Parks, or banning dredging in "all water courses ", in the country, ????.

Second , thanks for sharing your operation on the forum, I love the whole method, machines and all, simplicity in action, best of luck with the Government,

I hope you don't mind me pointing out some points of interest in your operation video for the rest of the guys, and the new guys too, especially the new guys, by new guys I refer to myself who after over 30 years mining with a passion only A FEW DAYS AGO, LEARNED, well i am suggesting / and hopping, I have learned something new, something the very new guys should /could consider, when ya out looking for some gold, and what gravels they may have in which ever part of the world ya in,

Ok, it is all about watching finnishdiggers vid link, first pic in my mind is how easy and well f/d's bucket digs , looking at that bucket and pay gravels, and "why it is so easy " for the water jets to break up and wash gravels out of the bucket ", ?????, N/G please note the rocks slidding off the screen has no clay balls or clumps of clay,

I am guessing that much gold in the pan, would possibly mean f/d is in the pay run, I note this because in my experience in Auss , NZ, Tassy ,there would be some or lots of clay, ??.

Please also note , that the bucket has no teeth, it is a blade, but still digs well, in my experience I /we use teeth on the bucket, because of the clay ,and also I suggest that F /D's gravels are "softer " then river gravels I have experienced, which are harder " packed ". in gold runs,??.

Next is what clues did I see when F/ D cleaned out his sluice,

After that , what clues did I see in F/D's Pan,

And What clues / observations did I see in a sample under my scope from Finland that are relative ,

More on that asap.sorry,but at least I have shared some thoughts and suggestions, a start is a start,

Kaveman,you say.
Ahh, no rush at all. Looks like nothing's going to happen until September at the earliest. So far, all I've done is corral a couple of ripper shanks off a Cat dozer. Missed a great deal on a 24" bucket that could have been modified for my machine relatively easily,..............but I hesitated since it was 2000 miles away. I coulda shoulda bought it. Might still get another chance at it as it didn't sell but it also hasn't been relisted yet.

Been there done that,, :smile:, later,dredger,:smile:

Ps, still trying to find time to finish those bucket dias too, sorry,

dredger
05:20:50 Thu
May 27 2010
Re: Dredging w/Hydraulic Excavator
Ok, back again,

Ok F/D' s sluice , the video sweeps up the sluice, riffles first, no problem, then sweeps up the expanded mesh with one of the miners moss type plastic matting under the mesh,, which show almost no river gravels or black sands , recovered or retained behind the expanded mesh, ??. for the new guys, my experience is there is always atleast some black sands somewhere, please note when F/D knocks out the mesh frame and turns it on it's side, please note, the finer sands stuck at the head of the screen are a lighter colour, perhaps more browner then black,

Next is when F / D pans out, there is almost no real heavy black sands visible, just lighter colour, and lighter Sg tan sands,moving in the pan and around the gold. AMAZING TO ME.

As to my sample from around that area, I did receive it a few years ago, and was amazed that I could not see any black sands in the sample, unfortunately, I lost contact with the owner of the sample just before i could get permission to pic and post the on the forum, I have and did wonder why there was no b/s, but only when F/D showed the video did i think or learn that F/D is dredging in heaven , haha, NO BLACKSANDS, and suggest there may be other parts of the world that also do not have black sands as well, for the new guy , my kind of dredging with no black sands would be heaven, I dream of dredging with no black sands cause there would be no heavy Specific Gravity to pick up and throw, heaven,

Finnishdigger, nice operation, and I am very happy to see ya family there too, good luck in the future, :devil:. and I hope you don't mind another suggestion which hopefully might help you to continue your operation, apply for a new license over the area, and explain you will reduce the work site " foot print " by modifying your method, to be only clearing a much smaller area, processing that area, and progressively back filling and re habitation to original contours, Take pics, before / during / and after , showing no visible change caused by your works, also insist you will recover all heavy metal " pollutants " , such as lead left by shooters, and fisherman, and also remove any and all Mercury left by previous old time miners, ( if there is good gold , it is likely the old timers where there, and used Hg to recover the gold in the area, ). please let me know if I can be of any help. and please consider some sort of suction concept to clean the bottom or water filled holes,

Hey Kaveman, please consider if you use a similar method and have clay and heavy black sands , it might require a lot more high pressure water jets to break up clay balls, which would jamb a screen similar to F/D,
:confused:.
back asap. dredger.:smile:everyone.

dredger
02:52:46 Sun
Jul 11 2010
Re: Dredging w/Hydraulic Excavator
Wow, bussy as,

Hey kaveman,

ok.sorry this has taken so long, the sucker, the blaster,with screen back flusher, camera and lights,excavator buckets " concept ".

Not the real thing, actually a toy, and quickly cut and assembled, a few pics first,

Oh please note, I intend on having an extremely high velocity vac and extremly high pressure and low pressure blaster,

Ok toy excavator bucket, ( no real teeth ).



please note, 4 thin " ribs " shaped to the " back" or rear of the bucket, ( only card board and painted in blue ), as with most concepts, this proto model has 4 rear ribs, the real bucket may have 6 or more, ??. see what happens when building it, ribs could be profile cut and 2" or more inches thick,the ribs are part of the blaster concept,

Inside the bucket,



Please note 3 ribs,fit inside bucket,I later cut them back a bit, and added a cover plate,



testing,


dredger
04:01:12 Sun
Jul 11 2010
Re: Dredging w/Hydraulic Excavator
A few points of interest are,

The size of the screened materials would or could vary according the different areas, and I am yet undecided on my area, and the % of small to large rocks,so the model is no real indication of the/my screen size,

One thought might be to process 3" and under, meaning the slots could be 3" wide and 6" or more high, ??,

Or 1" wide and 3-6" high, at this point I am undicided,

Another thought is the bucket would loose volume with a screen/plate mounted inside the back bucket, plus the fact I am considering or want a 2 cu mtre. / yds bucket of materials moved with each pass, so the line of thought is I will construct a 2 mtre /yd bucket,

For the new guys, please note a 20 ton excavator usually uses a single or just under one cu mtre /yrd bucket, works and digs well, but / and or a 30 ton excavator usually uses 2 CU MTRE /YD bucket, close to 2 yds wide,which is fair enough, and will dig well because it is 30 ton machine, so my line of thought is to build a bucket with 2 cu mtre cap, with a one metre wide mouth, and fit it to a 30 ton machine, resulting in very easy digging, ( for a 30 tonner, ) and my required 2 cu mtre per pass, 6 seconds,

Now back to the ribs on the back or rear of the bucket,and blaster manifold,



testing.





dredger
04:19:05 Sun
Jul 11 2010
Re: Dredging w/Hydraulic Excavator
Next a 1" cover plate, ( pink paper ) , and please note i have drawn a pipe fitting on the plate, high pressure water is pumped in,



And exits or is forced out through the slots, High pressure and around 1 and 1/2 cu mtres of water in under 2 and 1/2 seconds,

So that when the bucket is being forced into the gravels at or on the bed bedrock,


The jet of water is direct forward under the bucket teeth, hopefully blowing gold out of crevices and gold laying or dropped on the bedrock to blow forward, and then hopefully will become affected by the suction inside the bucket,

dredger
01:51:49 Mon
Jul 12 2010
Re: Dredging w/Hydraulic Excavator
So, bottom pic shows the bottom of the bucket in a flat on bedrock scenario, high pressure water blasting from left to right,and sqeezed under the bucket to the work face ok, big problem here is, keeping the bucket flat or at slightly more angle so as not to drag the rear / bottom of the bucket on the bed rock, and just keep the teeth slimming over the bed rock,and feeling the bedrock, the high pressure and correct angle should keep the blaster slots from blocking with rock, the slots could be 2 - 3 "s deep, by the width of which ever bucket,figure that out as required,

For the new guys, the truth is the bucket is likely to be under dirty water, 6-8 feet deep,and or the dipper arm can also be under 16-20 feet of dirty water, and if ya have the boom half under dirty water at around 27-35 feet deep, you or well I, have never been really sure if the bucket is flatish and the teeth a just skimming the bed rock, 6 times a minute, 12 hours a day, none stop while the going is good,generally speaking.

So what I had in mind next time i dredge, was to fit a simple mechanism,to the excavator that would give me clear vision and exact position/ angle of the bucket and dipper at all times, be handy for learning, so the scenario is I/we am sitting in the cab, hands on the controls, watching everything through the front glass or open window of the cab, also using our perifial vision, ( hate a spell checker that does not know everything, ) on the left is the open door, or open glass on the door, and on the right is limited vision of the right hand side of the cab and machine, limited by the boom, big fat boom, my idea is to mount it right there,on the boom, the indicator, would consist of a 10" x 2" strip of metal a few mil thick, representing the dipper, and a 4" x 4" flat steel, representing and shaped like the bucket, screwed and pivoted against the side of the boom, ( right in ya face, ), two or perhaps more light weight " push / pull cables, attached the the pusher arm, and one at the dipper / boom pivot point, actually i would suggest the idea is so kiss, and it will work,not forgetting that it will not show depth,unless you want to make it a little more complicated,

So back to the bucket,


So back to the bucket,


kaveman
06:03:20 Mon
Jul 12 2010
Re: Dredging w/Hydraulic Excavator
I'm still following, but wow,...........by my calculations 1.5 cu meter water per 2-1/2 seconds equates to 10,000GPM. That's the output of 6-7 P1500 pumps and roughly 400HP. Obviously it only runs in spurts, but that's a pretty impressive spurt!

dredger
07:49:03 Mon
Jul 12 2010
Re: Dredging w/Hydraulic Excavator
No worries, aim high, haha, as long as I end up with a impressive spurt, that will be ,I think at first spray or splash muddy water all over me and cab, ( in say 4 ft deep pond, ) untill i back off on the throttle,and or perhaps decrease the size from 2 cu mtre down to one, maybe that is all that will be requiried maybe a 1/2 cu mtre of water, to blast the bedrock, and sweep any /all gold infront of the bucket, and hopefully break up, or loosen up the face,

Also perhaps some already processed or heavy black sand materials can be added to the blaster to make it a grit or wet sand blaster affect,

Yes, 2 and 1/2 second spurts, timed in sequence in a 6 second pass,it was also my intention to place small electric trip switches on the bucket/dipper angle indicator, mounted on the boom, to stop false or wrong bucket angle spurts, working on that.

My line of thought is not a P1500 water pump concept per-say, it is a cylinder and piston,( suck and spurt ) in fact a number of rams and piston / cylinders, the blaster will have the bigger cylinder, and the others will be used in the filtration, and moving / dewatering / filterable solids / gold / water through recovery system/s/s/s, ect,working on that, too.

Another post coming asap.,

dredger
08:27:57 Mon
Jul 12 2010
Re: Dredging w/Hydraulic Excavator
Please note these are only first proto type concepts, and certain aspects of the the model will have to be modified, such as high pressure water flow, through or around the ribs, or removing parts of the ribs,to ensure correct high pressure flow, and correct suction feed behind the screen,

Also it will be my intention to fit a small zoom camera /s and lights inside the blaster manifold,to be used when the pressure / volume of water is greatly reduced to displace dirty water and get a good look into crevices,( in a dirty water work hole,

Interesting here, is the proposed source of high pressure bursts and low pressure filtered clean clear water supply,

the high pressure blaster will use some over 200 hp ( of a 350 hp unit ) driving a 100 gpm hyd pump, with enlarged porting and hoses, to a large ram, similar to a / one 30 ton excavator " boom ram " which will drive a piston type cylinder water, ( syringe ).2 cu mtre capacity with an outlet size of around 6" heavy duty high pressure hose, some 32 ft in length, to the blaster manifold,

The low pressure clean water supply will be sourced from the processing plants, " de-watering / filtration system ", and also a 2 or 3 cu mtre capacity, which should allow a few minutes to search around a small area or surface of the bedrock, for missed gold, and crevices,

Scenario could be, remove overburden over small area / surface of bedrock, within the reach of the machine,

Place the bucket flat and horizontal, on the bedrock, and open the bucket ( un - crowd the bucket, )to half way of vertical,( or less ) and engage clean water supply, and watch the small close circuit TV screen mounted in the cab, hope will show clean water " dispersing the dirty water with clean water, which should give good vision of bedrock about the width of the bucket and or by a few feet behind the bucket,which effectively sandwiches the clean water, while slowly moving or sliding the bucket teeth around the cleared work area,
:devil:
:smile:.

Lighting is next, with a lot of choices of natural lighting colors, which can help make the gold on the or in the bedrock brighter, and more visible.

Another pic shows white out sections in which the suction manifold is fitted and welded,



back soon,


dredger
01:27:39 Thu
Jul 15 2010
Re: Dredging w/Hydraulic Excavator
OK, bussy as here, but ,:confused:, this concept is still coming together and evolving as we go,

After, alot of thought about a bucket suction manifold, I tried to sketch a suction on the back of the model bucket piced above, present some probs, so lets first consider the " factors ". which may explain or help me to get the suction manifold to work,

Thanks kaveman,nice to have some figures to work with, :smile:

MATE, i am so preoccupied with family probs, I cannot get my head around working out " how long would a 8" hose have to be if it had say 1 cu meter of water / slurry inside it ",??. be a great help please,

1.5 cu meter water per 2-1/2 seconds equates to 10,000GPM. That's the output of 6-7 P1500 pumps and roughly 400HP.

Guys please note, I am guessing most of this, as we go,

Factors, concerning the suction manifold,ect,

I want to suck wet / dry vacuum 1.5 cu meter of water or a undersized gravels, wet slurry, in 2.5 seconds, long tube of slurry, with ?? perhaps 10 foot of lift,

The suction manifold will have to " gulp up " 1.5 cu meter or perhaps a more realistic, 1 cu meter of water /slurry, per 2.5 secs, with around 350 -450 HP, and a mother of a sucker pump, hold on, my intention will be to run this concept flat out, and then throttle back for good fuel eco and make the plants last, so please don't think this thing will be running flat out, no.it will be strong,

For the new guys here, costs are a big factor in running a operation, fuel for these machines per second, thats 2 x 350 hp excavators, and 350 to perhaps 450 hp processing plant, please note ,the excavator /s x 2 or x 3 will be very economical due to the fact that most of the time they will only be using just above half throttle.

Sg of those gravels would have a factor if not for the extreme velocity, My line of thought is a simple scenario of getting a foam tub slighly smaller then my heavy duty wet dry vacuum cleaner say a few feet long,and feed it in the nozzle, thump it is gone, ,

Sorry gotta run back asap. dredger.

kaveman
02:44:32 Thu
Jul 15 2010
Re: Dredging w/Hydraulic Excavator
It would take 31 meters or nearly 101 feet of 8" hose to contain one cubic meter of water/slurry.

baub
13:24:08 Thu
Jul 15 2010
Re: Dredging w/Hydraulic Excavator
If you can get a sufficient water depth, a simpler method might be an airlift style dredge. Uses 2 pipes and a large air compressor. One small pipe for the air going down and a larger one for the upchuck from the bottom. Needs 30 feet plus water depth to work properly and the deeper it is, the better it operates. Works well with loose stuff.
If complexity is not an issue, and you want to penetrate the bedrock, using this in conjunction with your 30tonner would require 2 people minimum and let your machine head stay down, reducing cycling time.
Action Mining has a compilation of articles from it's old magazine, Popular Mining. Volume 3, page 127 has an article that descibes this quite well. There may be additional articles as well. I would suggest reading this first and see if any of it applies to your situation.
The complete set is about $150 US plus shipping etc
Action Mining Services in Sandy Oregon, USA

b


dredger
20:16:49 Thu
Jul 15 2010
Re: Dredging w/Hydraulic Excavator
Hey Baub,
Thanks , and I hear what your saying, but I am focusing on the situation in my area, which is “shallow to bedrock “ river gravels, ( 4 - ? 20 feet deep ) line of thought with that is “ erosion “ is my friend, cause erosion will transport and concentrate most gold into a “ run “,on or above the bedrock, ( and collect in crevices, ect ), as it moves or erodes from the source or sources, and shallow bedrock means I only have to move the least amount of gravels to get to bedrock, actually I am intending that the whole operation excavators / processing plant all on tracks, will dig and work the work hole , and back fill the hole progressively at about 1.5 meters per hour, perhaps faster, ( work hole would or could be say 35 feet wide, x same front to back, )
So, basically a airlift dredge is unsuitable for shallow work, HOWEVER, thanks for the inspiration, AIRLIFT, AMAZING, I have been search for two answers, to two ??. irritations,
1, being what to do or what can I do with with the exhausted air blast created from the wet /dry suction dredge bucket nozzle concept,
2, being how to “ wash out “ ( or fine mud and clay, silt, fine light Sg gravels , and yes, fine small flaky flighty gold, and clean all other gravels in preparation for classifications, like when ya wash the dirty water off when panning,
3, possible line of thought is to add “ some airlift to the gravels washing process, I like it , thanks for the idea,
Thanks kaveman, 101 foot, wow, meaning around 33 foot hose would be around or just over 1/3 of a cubic meter of water, and 330 kg, also allowing for Specific gravity for the lighter gravels to black sands,??? Kg,rough guess, ouch, traveling at extreme velocity, :smile:.
Another factor is the suction will only be sucking inside the bucket for the or around 2 and 1/2 secs, in a roughly 6 second cycle, that will give me a few seconds to empty the sucked materials, and not suck water without gravels,
Also, arr, forgot, no, How many cub meters of screened undersized gravels are there in 3 cu meters of river gravels in " my area ", to make my point, a scenario could be,
1, i have a 2 cub meter bucket, and am capable of sucking 1 cub meter per 6 second or 3 cub meter cycle, in my area, river gravels are at a ratio of 1 cub meter fines of below screened size, Mixed with 2 cub meter of over size, ( just guessing ).
2, Same excavators and same sucker bucket processing unit on a beach, where mostly all is under size sand, and definitely not much oversize, resulting in this concept not working, due to suction cycle, which is related to processing,
3, However I would suggest that some river and placer / areas have different % of under / over size river gravels.
4, These above variables could be tuned by having a interchangeable sucker bucket screens which focus on screen size and total surface area of the screen,
So , the above is related to the bucket suction manifold , which I was previously talking, and I have been trying to find time to think about, please also note, that the bucket suction manifold, and suction hose connector fitting , will be incorporated with the high pressure bucket blaster concept hose connector / fitting, to back flush the screen inside the bucket,
To enable the operator to flick a switch , that will give the operator 3 settings on the suction hose, ( 8” ) “ VALVE / GATE “, first setting , AIR / SLURRY FLOW into processing unit, second setting , allows fresh air to enter the hose at the fitting, ( this is to stop further fine materials ( or small rocks ) passing through the screen while the over screen size gravels are being dumped into the processing unit hopper, ) third setting is to block the suction hose , which also engages / diverts / the or a high pressure water blast into the back though the suction screen in the bucket, and backflushing the screen, “ over the hopper “.
Out of time, but there is also a quick release and quick engage mechanism for the suction hose, and high pressure from the processing unit hoses,incorporated at the bucket,small package, thinking about it, do some drawings,
Sorry gotta run, docs again, back asap. dredger.




baub
21:58:18 Thu
Jul 15 2010
Re: Dredging w/Hydraulic Excavator
You're welcome. Good luck Dredger and pls keep us informed.

b

dredger
01:28:28 Fri
Jul 16 2010
Re: Dredging w/Hydraulic Excavator
Hey B,

Yes mate, thanks, the more I think about it, the better it sounds,:smile:. will do the best i can,

dredger.

dredger
05:20:41 Fri
Jul 23 2010
Re: Dredging w/Hydraulic Excavator
Been thinking about it some more, airlift , so a scenario could be, I want to thoroughly wash gravel, especially i want to wash out all super fine silt, clay ,fine flaky gold / splinters of any goodies and dissolved forms of heavy metals, ( quickly ) that do or can be washed away in a ? say 4" dredge sluice, actually any sluice due to overloading ect,, ( even though in alot of cases, a very good percentage is recovered by experienced and lucky miners ), and leave say 50 micron and up ball or chunky fine gold, ect, good heavy chunky gold will stay in the wash,
((( Please note, I will also or already have a low pressure/ high volume of water rising from below , so all dirty water slit fine gold will be lifted and will flow backwards and in to screened drains catching the over flow, so the dirty water / fine slurry flows into the overflow drain, and is high pressure hydraulically / filtered , and used for 4 purposes,
1, At low pressure is slowly pumped to the blaster slots /screen, to displace dirty water , so the lights and camera, inside the blaster and screen, give good vision at bedrock level
2, to displace or wash out the the gravels being washed,
3, please note , If I am sucking 1.5 cu meters of gravels, and there must be a % of water/gravels in each suck, also 2 cu meters of over screen size gravels , which also must have or contain a % of water, ( also please note I am referring to the water volume / capacity of the processing plant only ), so I am expecting heaps of water to filter and have to discharge off the moving processing plant, ))) which I am thinking is to spray the water / filtered over the back filled rehabilitated gravels , which should be pretty washed and layed to original contours, any way, please note the blaster will also require some 1.5 cu meters of water , per excavator, per 6secs , guessing, guessing,
Please note, everything, silt, ect that is washed out of the initial ( and final ) washing process is dewatered and further processed as a wet slurry, so lots or hopefully all fine gold , and also some accuracy in separating fine and flaky gold , actually all undersized, from the oversize materials being washed, a new thought is, ( just got this one, )??. How about a fluid, and air lift concept that washes away Black Sand, or washes black sand and larger size gravels onto over size black sands “ screen “ , allowing the average black sand size to pass, and larger size quartz and lighter larger gravels to be returned to the wash plant, ??. imagine that, the final oversize cons and gold could show or prove all black sand size black sands in those over size cons, has been removed and processed in or with other concepts,
So, some scenarios on theories could be, I get a plastic pan, large, and a same size, same type plastic “ dish “, and plastic weld the dish under the plastic gold pan, then turn the pan up the right way and drill say lots of 1/64" holes in the bottom and sides of the pan, and add a air fitting in the bottom of the dish,
Two possible scenarios,
1, Standard same size plastic gold pan, I would sit on a rock on the side of a river, and wash most of the dirty water out the pan while washing the or all the gravels clean, and ready for classification or further panning off, all b/s remaining in the pan, possible loss of small % fine or dissolved heavy metals, ??.
2, Same size gold pan with hydraulic and air lift bubbles while using the previous washing a pan with some clay, method,??. would that be faster washing, ?.
3, increase air and water lift to
Would the air bubbles streaming up help the washing process, ????. and attach to dissolved forms and or not fully forms of heavy metals, as well as ultra fine dust or silt particles, snacked by air bubbles as they rise, ??.
Over, and above water being also being pumped in from below,
While thinking about that , I also think about what sizes the sucker bucket screen “slots “ , and variables that could be interesting, as to width of the slots, deck height of the slot, ,
In other words , and first point of interest, the bucket could be 5-6 foot wide or more, ( standard 30 ton excavator and manufactures specs, ) , so I need 8” dia surface area across 5-6 feet of bucket, with screen slot sizes /widths somewhere in-between ½ “ to maybe 3” wide, ???, what would the deck height of the screening slot, the math’s makes me oozy, and dizzy, so my first thought is to half the problem and make / build a 2 cu meter bucket ( with sucker bucket manifold built in ), that is 3-4 feet wide , with the same or close bucket pivot point ,from and to the bucket teeth, measurement. Or distance,
Ok, for the new guys, a 3 foot wide bucket on a 20 ton excavator, moves loose, or ripped or blasted ground well, but when the ground is hard or packed river rocks and gravels, “ time is lost “ feeling and picking around the hard ground, and then moving up to a 30 ton excavator, the bucket doubles in width,, usually , but the total weight of the excavator only increases by 10 ton,
Back asap.


dredger
01:33:06 Sun
Oct 17 2010
Re: Dredging w/Hydraulic Excavator
Sorry , been real bussy, fact is i am still bussy, :confused:

Latest ideas on the size and shape of the suction screen inside the bucket are still coming,

Right now I have given considerable thought to " visual confirmation " using a vibrating feeder chute,

Please note, this concept is not a tuned recovery device, it is simply a device to give visual confirmation that the materials dug some few ( to 14 ) seconds earlier, " Do or do not " contain gold, please also note. my line of thought is there should be a vibrating feeder chute for each classification, x about 4-5 separate classifications, also please note each device will be mounted or situated behind the primary classification screens , and also have a closed circuit cameras, x 4-5, that feed visual conformation into a programed computer,that will convert and roughly quantify the amount of gold and also the screen size of gold passing from the primary classification into the secondary concentrating units,this info then can be transmitted to the operators by means of a 4-5 light panel, which would glow brighter for good gold, and not glow at all for no gold,

please also note, my focus with a concept 18 - 40 ton processing plant is to concentrate and provide surprising large amount of cons, containing hopefully surprising amounts of ultra fine gold,as well as the larger more usual catch-able gold, please consider I am hoping that the surprisingly larger amount of cons will be relative to the surprisingly high volumes of materials processed per hour,

Ok back to a sketch ,please note the chute dimensions would be or be much bigger, relative to the or which ever screen size,


please also note each screened sizes will be vigorously washed and contain no turbid /dirty water, mud, clay, light Sg fine materials, including very fine or small flat flaky gold, ect,as it passes over or along a vibrating feeder chute,

(1) back asap. testing.

:smile:

dredger
00:21:33 Thu
Oct 28 2010
Re: Dredging w/Hydraulic Excavator
Ok, lost a big one, so start it again,
And I put the numbers in the wrong place, sorry,
(3) is a hopper, which
(4 ) materials will be any of 5 different classifications, 0- 25mm/ 1”, 0-1 mm, 1-2 mm, 1-3 mm, 3-10 mm, 10-25 mm, screens,
( please note , I have some great ideas on “ revolving orga speed screening ΄ more later “, ) ,
Opps, got a few thoughts on , ?? a revolving ( orga or screw ) speed screen , ( please note, there are or will be 5 different or separate screen sizes, or 5 revolving ( orga or screw ) speed screens, ( self cleaning ) interesting possible points , are to first test, if the screen can be adjusted or tuned to give a %99.99 classification in less then or the first %25 of the length of the screen, ??. then be adjusted or tuned to give %99.99 classification using up to % 95 of the total length of the screen, ( maybe 10 -15 feet long x ?? 2 feet dia, ) resulting in good wear or long wear factors of the self cleaning revolving screen surface, HMM, and easy maintained, and easy hardfaceing to extend the life of the screen , there is also a question of “ what screen RPM would promote the best or most efficient tumble action to present under size screen sizes materials the screen “ gaps “, guessing, I would suggest 15-30 rpm for the screen , and 0- 10 orga rpm, please also note , the “ FIVE “ above shaking feeder / visual confirmation / revolving orga /screw speed screen and final fluid concentrating / process units, are focused on the “ under 0-25 mm or 1 “ size materials “ ,
Also please note, it will be my intention to wash “ off “ all silt / mud / clay, “ dirty water “ , fine flat flaky gold held in or have some tendency to be held in suspension for any seconds, maybe a lot of attached fine particles,, , and dissolved forms of all heavy metals, “ in the primary processing unit, “, MEANING there will be separate multiple processing recovery concepts/units focused on the fine materials washed off,
1,“ dirty water “ ,and dissolved forms of heavy metals, and filtered water recycling,
And 2 , “” “ all silt / mud / clay, fine flat flaky gold held in or have some tends to be held in suspension for any seconds, a lot of attached gold to fine particles ( quartz ) ,””.ect.
PLEASE ALSO NOTE, AND NOT FORGET THE OVER 1” /25MM SCREEN SIZE MATERIALS , and multiple processing concepts, still working on those concepts,

Better post, back asap, dredger.


dredger
05:57:50 Wed
Nov 3 2010
Re: Dredging w/Hydraulic Excavator
Ok, lost a big one, so start it again,
And I put the numbers in the wrong place, sorry,
(3) is a hopper, which
(4 ) materials will be any one of 5 different classifications, 0- 25mm/ 1”, 0-1 mm, 1-3 mm, 3-6 mm, 6-14 mm, 14-25 mm, separate screens,
( please note , I have some great ideas on “ revolving orga speed screening ΄ ,
Opps, got a few thoughts on , ?? a revolving ( orga or screw ) speed screen , ( please note, there are or will be 5 different or separate screen sizes, or 5 revolving ( orga or screw ) speed screens, ( self cleaning ) Interesting possible points when first testing , are to first test, if the screen can be adjusted or tuned to give a %99.99 classification in less then or the first %25 of the length of the screen, ??. then be adjusted or tuned to give %99.99 classification using up to % 95 of the total length of the screen, ( maybe 10 -15 feet long x ?? 2 feet dia, ) resulting in good wear or long wearing factors of the self cleaning revolving screen “surface “, HMM, and easy maintained, and easy hard/faceing to extend the life of the screen , there is also a question of “ what screen RPM would promote the best or most efficient tumble action to present under size screen sizes materials the screen “ gaps “, guessing, I would focus 15-30 rpm for the screen , and 0- 10 orga rpm, please also note , the “ FIVE “ above shaking feeder / visual confirmation / revolving orga /screw speed screen and final fluid concept concentrating / process units, are focused on the “ under 0-25 mm or 1 “ sized materials “,

Sketches coming , asap,

Also please note, it will be my intention to wash “ off “ all silt / mud / clay, “ dirty water “ , fine flat flaky gold held in or have some tendency to be held in suspension for any seconds, maybe a lot of attached fine particles,, , and dissolved forms of all heavy metals, “ in the primary processing unit, “, MEANING there will be separate multiple processing recovery concepts/units focused on the fine materials washed off,
1,“ dirty water “ ,and dissolved forms and semi dissolved heavy metals,
And 2 , “” “ all silt / mud / clay, fine flat flaky gold held in or have some tends to be held in suspension for any seconds, a lot of attached gold to fine particles ( quartz ) ,””.ect.
Again, please note, washing off dirty water, silt, mud, clay, will mean the gravels ect being screened through each of the 5 screens will be clean washed gravels ect,
PLEASE ALSO NOTE, AND NOT FORGET THE OVER 1” /25MM SCREEN SIZE MATERIALS , and multiple processing concepts for over 1’ materials, , still working on those concepts,



:confused:



Better post, back asap, dredger.

dredger
21:16:45 Sun
Jan 9 2011
Re: Dredging w/Hydraulic Excavator
Bump, back asap.

dredger
08:29:00 Mon
Jan 24 2011
Re: Dredging w/Hydraulic Excavator
Just take a break from the above vibrating feeder chute,sorry,


Kaveman,

Sorry but the penny just dropped concerning your post,

Re: Dredging w/Hydraulic Excavator "It would take 31 meters or nearly 101 feet of 8" hose to contain one cubic meter of water/slurry ".

True but i thought I would keep the super tuff, ( and most probably super stiff ) 8" suction hose between the bucket and the wash plant about 30 to 50' long, my line thought is exactly the same concept as a " wet dry vacuum cleaner ", where if the vac'ed water storage area in vac, is say 1 gallon, I can suck 3/4 gallon of water "continuously " and the hose fills up, and dumps into the wet / dry vac water storage area and fills up to 3/4 gallon, please note, most wet dry vacs have a cyclonic affect and separate the water / materials from the vacuum, which just blows out of the fan, vac air pump, I will follow the same concept, which seems to work well on my wet /dry vacs, Re: Dredging w/Hydraulic Excavator It would take 31 meters or nearly 101 feet of 8" hose to contain one cubic meter of water/slurry.

So the scenario could be, I pull the bucket into the work face, and hit a button which throws a valve to divert the vacuum to the bucket on No 1 excavator, I hope water and mostly under 1" materials are sucked through the screen in the bucket, and up say 30' of suction hose, and into a ?? 2 cubic meter cyclonic separator, it will continue to suck until the bucket is about to break the water surface and just after, 1 and 1/2 to 2 and 1/2 seconds, then the vacuum will be diverted to the other excavator suction bucket which is being pulled into the work face, giving or having a 3 second cycle between two excavators every 6 seconds, :devil:. :smile:. sucking about 1/3 of a cu metre up the hose at any time, ??.

Please also note , it is my intention to have a very powerful vac pump,

dredger.

RUSTY_HAPPY_CAM
18:10:52 Mon
Jan 24 2011
Re: Dredging w/Hydraulic Excavator
Dredger, sounds like a neat idea. However you are mixing to different types of suction systems. The wet-dry vac is a simple example of air conveyance. With that type of system air flow is what moves the material, the more CFM moving up the hose the more slurry you can take with it. Most city sewer cleaning trucks use this type of system. They can lift bricks from over 100' deep if they have enough power. The other type is pure vacuum. That type is often seen on septic tank trucks and require a completely sealed vacuum rated tank, similar to a boiler for the slurry to deposit into. The best vacuum pumps are rated to pull about 28" of mercury. This system works great at moving liquids. However the draw back is a pure system can only lift liquid about 22'-26' vertical at sea level.

dredger
00:23:08 Tue
Jan 25 2011
Re: Dredging w/Hydraulic Excavator
Hey Rusty,

Thanks for bring up those points, reminds me I was not quite clear in my description of a wet / dry vac, I did forget to mention included in my ideas on " this " "or the vac pump " I intend on using is also , a vacuum pump used in Australian Opal mining, it is a dry vac,

Strangely enough Aussie opal Miners call it a blower :confused:.

They use a 4-5' dia impeller / "fan " housing with a 100 -200 HP diesel engine,and I intended on using about 7-8' dia air pump / blower and at least 350 Hp, to produce extreme line velocity, I am not sure how much I will be able to suck in such a short time, but I really want the maximum line velocity and Torque, ( if Torque is the right word, ?? ), you know "grunt ", if it pulls 1/2 cu meter in 2 secs ?? maybe 3 secs, it will be a useful tool. if it pulls or sucks 1 and 1/2 cu meters in three secs, I will be very happy,

I also have ideas on a very quick hitch concept for the suction hose and high pressure blaster hose line, where it attaches to the bucket,( and stretches up to the wash plant, ) so that I can very quickly disconnect and connect it, I am looking for is the fastest quick hitch ever, meaning or involving 2 concepts, No 1, being when the excavators are working a 6 sec cycle, the distance between bedrock and the top of the hopper , in the full production mode, sequence, the hopper will be continually presented to the bucket by the mobile wash plant, deep in the hole, while in full production or digging mode, the bucket will travel the shortest possible distance in the shortest possible time, maybe 3-4 meters, with perhaps only a few inches clearance,between bucket and hopper, the cyclonic separator would be very close to the hopper, so I am hoping to the suction hose will end up being as short as 3-4 meters, well that's the plan anyway, it is also the idea that the hopper will reach down into the hole, and maintain a few meters from or height to bedrock,

No2 , is the fact that continuous 6 sec cycles will not happen for any more then a few minutes, I am hopeful for lots of minutes before the operator has to disengage the quick hitch ,and reach or push a large rock or log,ect further away that is not intended to go in the hopper,but rather cleaned and placed / stacked / pushed on the other side or back of the work face, and be the base on bedrock level for back filling the work hole,

So, My line of thought is build a "electro- magnetic " quick hitch, for the suction hose /high pressure hose, between bucket and the wash plant, the E/M quick hitch could be mounted a feet above the bucket, and mounted to the dipper, a few feet above the bucket, with a flexible coupling to the bucket, the end or the bucket end of the suction / pressure hose would be attached to retractable cables, please note this is the other half or part of the E/M quick hitch and remain suspended near to the the hopper, as the operator returns from pushing or moving bigger rocks to the work face, he quickly presents the two half very briefly, and the electro magnet will place and lock in both half's, this should happen while or as the excavator arm passes and not have to stop or slow down much to attach the above hitch ,Practice makes perfect, and electro - magnets work in split seconds,

With a little luck, I will be able to back it off the vac pump enough to get a fair suction and fuel economy, and production, we shall see,

Ok, considering I purchased a 40' shipping container yesterday, cheap too, pics coming but the camera NOT WORKING,yet, so they will have to wait, however I am thinking about how to set up a mobile wash plant,using 20 -30 -40 shipping containers, and where the advantages and disadvantages may be theorized,

back asap,
Ps,
Hey Rusty, what do you think, please.

, :smile:

dredger
01:58:59 Tue
Jan 25 2011
Re: Dredging w/Hydraulic Excavator
So the idea is crazy, but lets look at it anyway,

One of the things i like about a Mobile set up is it is meant to be moved easerly and quickly from site to site, and test hole to test hole,

So,


testing,

dredger
02:22:50 Tue
Jan 25 2011
Re: Dredging w/Hydraulic Excavator
Arriving on site, 2 x 20-30-40' shipping containers, please note the containers are in blue, the red lines on top of the containers are heavy bracing and supports,disassembled and packed on top of each container for transport, the thick light blue line is weather proof walls that fold out and assemble as weather proof control and work areas, maintance area,ect, ,

Option No 1,
.



RUSTY_HAPPY_CAM
02:36:36 Tue
Jan 25 2011
Re: Dredging w/Hydraulic Excavator
Excavators and wash plants are out of my comfort zone. I do have a 30 year background in the use of fan and PD blower vacuum work. You will need to do a lot of study on just how the opal mine blowers work compared to your idea. Basically a positive displacement or PD blower is about the same as the superchargers used on drag cars and older diesel trucks. They are the middle ground between high CFM fan units that are normally used for dry suction and the low CFM high vacuum rotary vane style used on septic units for liquid pumping. The high end PD blowers can approach a pure vacuum rating and still move high CFM but they are very expensive and require extensive safety systems on them to prevent any dirty air or God forbid water from entering the compressor chamber.Their tolerances are so close and they spin so fast that even small amounts of debris can cause catastrophic damage.Here is a web link to the largest supplier of blowers. http://www.dresserroots.com/

dredger
07:19:53 Tue
Jan 25 2011
Re: Dredging w/Hydraulic Excavator
Ok Rusty, thanks for the heads up and i will do further investigation,

Better to get some good help here , before I waste money Aye, ??.

I understand the PD ROOTS TYPE concept, and agree is basically out of the question, but I still like the Australian Opal blower fan, cause of the much shorter suction hose, along with say 3 cyclonic separators before the fan bladed pump,??,i would expect some condensation to reach the pump.

Anymore thoughts please Rusty,

RUSTY_HAPPY_CAM
18:54:39 Tue
Jan 25 2011
Re: Dredging w/Hydraulic Excavator
Fan type units in use here in the states remind me of multi-stage squirrel cage fans used for furnace blowers. Here is the top name in the 3 stage fan cleaner units.http://www.vac-con.com/ There are larger units and units with more stages that have been made. I just can't find a link right now. The 3 stage fans move around 8000 CFM and pull around 10" of mercury up an 8" hose. I have several thousand hours on this brand of equipment. I don't believe it will do what you envision. The problem is you are sucking a submerged slurry. Fan type units really need air flow to move the material. Since you are using a submerged hose you are going to be better off with a giant rotary vane pump or PD system. However both will have a limit of how high they will lift without air injection.

dredger
01:01:28 Fri
Jan 28 2011
Re: Dredging w/Hydraulic Excavator
Thanks Rusty.

You say, " The problem is you are sucking a submerged slurry ".

yes, I think the bucket will be submerged, and a short distance up the dipper, say to be safe 2-3 meters submerged, , do you think would kill of make that big a difference,??.

I also hear what you are saying here, "Fan type units really need air flow to move the material " . .and agree and suggest watching the / a suction and water/ materials traveling along my suction hose is less velocity and gives a more visible confirmation that materials basically only move along the bottom of the hose, so as you say , alot of air flow is required to carry a tube of slurry.,
, But I did want to really the fan much faster then ?? what is the usual for all other purposes, and have a rather large " fly wheel weight " inline with the fan as well. I also have seen how slow the opal blower had to be feed, but was thinking it was slow because we could not dig so fast,

Also this could backfire and if i did get enough suction to pull a cu - meter, that high velocity might just block the screen, by pulling bigger rocks onto the screen , I was thinking as the bucket crowds or fills, larger rocks would be forced across the screen and keep screen clear, ??.

Another point of interest here is I very much appreciate your help, so please note, I have another ?? concept .different from the fan type concept, if the fan concept fails, I was going to plumb into the high pressure water blaster, system, similar to a nozzle jet for a 8" dredge suction nozzle, a sort of a blast and suck concept, :devil:, and if my bucket sucker idea does not work I can still fall back on a excavator being able to deliver a cu - meter in seconds, and two excavators delivering a cu -meter in

Any way Rusty , thanks for the help, and I would appreciate any other comments please, it all boils down to me not wasting money,

Back asap. dredger.



More wild ideas on a mobile wash plank coming asap,

ME
18:33:23 Fri
Jan 28 2011
Re: Dredging w/Hydraulic Excavator
Any way Rusty , thanks for the help, and I would appreciate any other comments please, it all boils down to me not wasting money,

Who are you kidding Phil? We all know you Aussies are made of $$$ haha. Good to see your still exercising your brain. I'm thinking of jumping back into the pool this season albeit the shallow end since I can't just break off a finger and buy a new dredge. Take care, Mark

dredger
01:33:40 Sat
Jan 29 2011
Re: Dredging w/Hydraulic Excavator
MARK, what a great surprise, :smile:. how ya been, :welcome: back,

Great to hear ya getting back in the water, you better do it right this time, and actually catch some gold, :devil:.Haha.

Mate, I hope ya gonna keep coming back to the forum and keep posting, you know you enjoyed the fun before,

And I wanner get you back for that " Who are you kidding Phil? We all know you Aussies are made of $$$ haha, CRACK,HAHA, pm ya soon.

aNYWAY FLAT OUT FOR TIME, SO BACK ON SUBJECT,

Rusty, mate , sorry, i have a reply to ya post I have not quit finished, just gotta check it , I will post asap, thanks again for ya help.

Just wanted to quickly show a few more ideas / /sketches on mounting shipping containers on a mobile base, or large excavator undercarriage,

I like this idea better, because over all side mounting, 40 foot containers x 2 will allow me more floor space, and upper deck space,

And the chance to build a fairly strong base for mounting or side mounting 2 containers, the same size as a 40' container, so that the about 3 x 40' containers, say 8' x 3 = 24' wide x 40' long, 14 to 16' wide track base, 4' -5' over hang, on each side, ?? . I would suggest it could would be very stable for moving around considering the would be 1-2 x 30+ ton excavators to even the ground where would travel to access each test hole, and rehab where required,



So, we arrive on site with two containers and the center unit mounted on tracks, also already carrying a container size portion of the wash plant, ( basically all the heavy pre- wash and classification heavy machinery/ motors, ect,ect, ) this will keep the bulk of the weight in the center container area, over the undercarriage,

Please note , the total or moving / mobile weight of the complete wash plant will be much lower when it is not loaded and actually washing dirt, I am guessing assembled wash plant weight around 35 ton, I would suggest at 35 ton, the wash plant would be very stable and able to move from assembly point to and for many miles,

However, when the wash plant is processing, and full of water and gravel, the weight will increase, ??. I am guessing when i suggest, the wash plant will perhaps hold about 20 cu-meters of rocks and slurry, ( point of interest here is it would be my intention that the filtration system would or will work very quickly under high pressure, and the dirty water filtration and " heavy metal recovery concepts " will hold as little water as possible, and as little excess weight as possible , meaning the 20 cu-meters could be or weigh up to a scary total weight, but, considering the larger track base, and the intention that the wash plant will lay or drop it's own washed gravel base to track over,at and from bedrock level, from experience I would suggest laying the base gravels for the wash plant would result in a very stable machine, and safely carry heavy wash plants, blar,blar. ,

My line of thought would be to use a 45- 65 ton excavator track base,
'

Ps, new guys please note, working in a water way or river can flash flood, in my experience I have around 12 minutes to clear my work site before a flood washes most away, so it will be my intention to while the wash plant lays the gravels to track over , it will also back fill the hole in original contours, as well as leaving a "ramp " for the wash plant to reverse out in times of floods,
testing.


dredger
01:36:08 Sun
Jan 30 2011
Re: Dredging w/Hydraulic Excavator
Top view shows No1 as a area, where the primy wash and classification is intended,

No 2 would be motors pumps ect, all the main weight in the center , ?? pod, ?? over track base,.with both 40' containers attached, 960 sq feet floor space, lower deck, ,

No 3 and side view shows " upper deck " weather proof, area for final clean up. ect,

Please note, the red lines indicate,



Also please note, the upper decks will slew, or rotate, on the track base, and will also tilt, front to back ,

back asap.

RUSTY_HAPPY_CAM
17:42:07 Mon
Jan 31 2011
Re: Dredging w/Hydraulic Excavator
Dredger have you looked at the thread "NZ mining"? I think picture #40 may show one of your opal blower units. That unit is a single stage centrifugal fan. The link I gave you to Vac-Con shows 2 and 3 stage units. Their parent company made 6 and 8 stage units. Normally each stage increases the suction power. However that type of suction system loves air, the more air in the suction pipe the better the material moves. No air like in a submerged suction will limit the lift to whatever inches of mercury your unit can pull. With a maximum lift height at sea level of about 22'for a full vac rated unit.

dredger
07:20:01 Tue
Feb 1 2011
Re: Dredging w/Hydraulic Excavator
Thanks Rusty,

Funny ,opal mining on NZ dredging thread,:smile:, why not,

NZ excavator dredging, been there done that, don't know why I left,

I hear you and am trying to do a few sketches,

Thanks again, back asap. dredger.

dredger
01:30:21 Wed
Feb 9 2011
Re: Dredging w/Hydraulic Excavator
Hey Rusty,

Been thinking about it and ya right, the dry /wet vacume may only work enough to be a pain,



1, being a " inline air pump " I was thinking of building both the opal miners and the inline pump to see which would work the best, interchangeable . ??.

2, is some materials being sucked up useing the opal miners pump,

3, could be my larger modified home made air pump, slightly more vac and materials,

4, is you are right , i can not be sure I will get the grunt to vac a tube of wet slurry, so I will add an educator jet concept too to lift , considering the force the jet of water will have,

5, A large hyd ram, ( boom ram off a 65 tonner ).


6, a 1 and 1/2 cu meter piston cylinder with the hyd-ram forcing water at extreme pressure to ,

7, a eductor " type concept " jet built into bucket screen/nozzle , ?????. which should be well submerged, when the ram forces water to the jet, ??. the orifice could be around 3", with a 3" line with that much pressure ??, trick would be timing the high velocity air vac with the high pressure jet, ??. it has to work, with the added bonus of leaving the vac on in the hose longer then the high pressure jet , leaving the vac to ensure the line is keep clear and clean, between each cycle ready for the next cu-meter gulp of undersized or screened slurry, ??.



Another mad idea i had, was actually a compromise, arrrm , :smile:


I have struggled with a excavator about 35 ton, and the single mindedness that the bucket should be only 1 meter wide, with a 2 cu meter capacity,

35 ton machine in my mind is as big and fast enough with a 3 cu meter lifting capacity, and really swing it about,

So I am suggesting my line of thought is a 35 ton excavator could have a 3 cu-meter capacity and a 1 and 1/2 meter wide mouth, or width, please note the larger machine sits very stable while ripping through a work face in my river gravels situation ,

And 20-25 ton excavator could have a 2 cu-meter capacity and be 1 meter wide, is capable , it is a little more unstable which the operator should adapt , and have some fun, :confused:

Back asap, thanks Rusty, what do you think, please,

RUSTY_HAPPY_CAM
03:08:16 Wed
Feb 9 2011
Re: Dredging w/Hydraulic Excavator
Most any of the ideas will work to move material. The question is is it feasible. The rotary vane pumps and the PD blowers can suck as close to pure vacuum as you can get. The problem is that is only good enough to move a solid column of water about 22' vertical at sea level. To increase the velocity and the lift height air induction at the nozzle end works well. A high CFM low PSI compressor works best. You may have seen this principal used with treasure divers recovering gold from shallow wrecks in the ocean. As the air bubbles rise up the tube they expand and lift anything in their path also bringing cooling air to your suction units. However the big problem as I see it is the shear size and complexity of your set up. It is fast approaching a full time job for a large crew.

overtheedge
06:17:47 Wed
Feb 9 2011
Re: Dredging w/Hydraulic Excavator
For the most part, you all are thinking outside my knowledge base. A couple thoughts though.

Air-lift pumps don't start to shine until water depth hits 30-35' or so.

Hydraulic elevators work from 0' to over 100'.

So a thought is hydraulic elevators shielded by guards under the bucket. After all, hydraulic elevators are just reconfigured suction nozzles. If you need more boost, use inline jets. Except for the pivots on the boom, all the slurry could be in pipe with hose at the pivots. Put the jets in the fixed pipe.

Keep in mind that the quantity and pressure of the injected water (6&7) is limitted by the GPM of the hydraulic pump. The question becomes one of complexity and risk. Using an inline jet with water is straight forward and no risk of hydraulic fluid escaping into the environment. Keep in mind that the cylinder pumping the water is cyclic. Boost- nothing - boost - well you get the idea. Why not just use a high pressure water pump for the inline booster jet?

Ask yourself this, "Are the potential hassles and expenses of a possible environmental clean-up worth the additional use of petro-based hydraulics for boosting the material to the sluice when water is so easy to use as the medium?"

Now consider the fabrication costs. Hydraulic pump v high pressure fire-fighting water pump. 3000 psi @ 50 gpm v 125 psi @ 150 gpm are close to the same price. Hoses? Fluid? EPA? Cycling of your system v continuous boost?

Just my best guess. Do whatcha gonna do.

dredger
03:21:59 Thu
Feb 10 2011
Re: Dredging w/Hydraulic Excavator
Wow this is great, guys, thanks for thoughts, I have read them a few times, and i think I need some ram specs, and hyd pump specs, which I do not think i can find, :confused:., I think the hyd pump I have is a gold cup series, around a 100gpm and I think around 5000 psi,chatter box ect, ?? requires around 350 HP +, AUD $32,000 should be plenty to fast forward ( and reverse ) a big ram, and in turn force a piston into a cylinda, No 5 and 6, spit out 1 and 1/2 cu meters of water in a few seconds,

two things that sticks here is,

Overtheedge you say " Keep in mind that the cylinder pumping the water is cyclic. Boost- nothing - boost -",

I was thinking it is boost or rather compression, then on the return cycle is the suction, to refill the cylinder with water, No 6, ready for the next compression,please note, I need the suction cycle to suck basically dirty water though a or several, " self cleaning or clearing filters ", please note, there will be many, ?? or as many as required no 5 and no 6 units,( hyd ram and water compression and water suction piston and cylinders ),?? Maybe six - 9 in all, many electric/hyd valves to control hyd ram speed and distance which it travels, , and some serious thought about compression/suction cycles, a few seconds each within a 6 second pass, which is a 6 second cycle ?? So I am suggesting the massive engine, massive hyd pump, and hyd ram,annd water piston / cylinder. along with a "hydraulic elevators are just reconfigured suction nozzles ", built in the bucket,as you say, ( I like that, deliver after testing various Jet orifaces about 3/4 and or perhaps more then a cu-meter of "extremely " high pressure filtered water into the jet, over say 2 and 1/2 seconds,
2 points of my interest here, blar, blar,
1, I will bet money that considering the bucket will be submerged, the bucket position or angle, will mean the hose after the jet will be straight, and stretched stiff and straight, ( I also like your suggestion ) on inline jet, I will do that, above the hose coupling, and have one jet in the bucket, and another inline, maybe half way up the hose, I like it, with another my ram piston cylinder compressed high pressure concept,delayed a split second, very good,


So 2, that is 3/4 cu meter clean water, and how much slurry, ?? , and how much water can or will be sucked into a excavator bucket that is full of gravel in order to wash /suck all or most under screen size , I really want at lest a meter of under screen size b/s and anything under say 1" or perhaps under 3/4" , please note, both the under size sucked up and the oversize up to anything that fits in the excavator bucket are both then feed together into the primary washing / classification, hydraulic elevators are just reconfigured suction nozzles,

And , Rusty , you say " It is fast approaching a full time job for a large crew. ", no mate, one man excavator, one man wash plant operator, and one man wash plant tender, who will remove the concentrates, refuel, and rotate with the other 2 operators, please note my line of thought is the wash plant carry as little concentrates or b/s as possible to allow more room and less weight in and on the wash plant, please also note when I refer to a mobile wash plant, I really mean a bulk concentrator, which i hope will supply me with bulk high grade concentrates, which will basically be trucked out 3-4 times a day, nice small truck, ok I am dreaming the tender truck backs over the level rehabed river gravel, and attaches to the wash plant using a tow ball hitch , the truck is then .

Oops sorry gotta run , back asap.

Thanks guys,:smile:

dredger
22:28:42 Thu
Feb 24 2011
Re: Dredging w/Hydraulic Excavator
and attaches to the wash plant using a tow ball hitch , the truck is then .

Pulled along with the mobile ( slowly moving, ) wash plant, the truck would be fitted with a hi-ab ( truck hyd crane arm, ) with a 44 drum clamp, and load empty concentrate drums onto the wash plant, and or load fuel drums as required to keep the wash plant and excavators running, with a emphases on having a few hours fuel on the or weight of fuel on the wash plant, again please note this concept is a wash plant and bulk concentrator, meaning the tender truck would be continuously removing 44 gallon drum size containers of concentrates,from the wash plant, with the emphasis again on keeping the weight of the concentrates off the wash plant, asap, please note, that is my intention to be ready a lot of concentrates, 2 reasons being, if , I can dig and suck say 3 cu-meters per 6 second cycle, x 2 excavators, that could be around a cu-meter per second, yes, I know there will be reasons why I will not be able to maintain continuous cycle after cycle for long periods, " big rocks ", dead buried trees, cleaning crevices at and on bedrock. ect,ect, but , if I am able to maintain short bursts, over a 10 hour shift, a scenario could be both excavators dig and suck 3 cu meters each or x 2 excavators for 1 minute, wow, ( I am worried too, ) 60 cu-meters, straight, one after the other, about a second apart, Ouch,

Assuming the wash plant is or has a + or - 20 cu-meter slurry capacity larger rocks, as well as a 20 cu-meter dirty and clean water capacity, 20-25 ton wash plant and under carriage track base, weight , 60-65 ton loaded all up, I might have about 20 seconds to concentrate each cu - meter, to how much concentrate,????. to retain all the gold in that concentrate,and not wash or loose any gold out of that concentrate in the wash plant, by "any" I mean 99.9% gold retained in the cons, meaning a lot of " extra " cons, perhaps starting recovery of con cons at 1 ton per hour, maybe 5 ton of great cons per hour " recovered ", ??. nothing larger then a few inches, separate 44 drums marked (1). few inches cons, (2). one inch cons, (3), 1" - 1/2" cons, (4), 1/2 -1/8'cons, (5)1/8- 0" cons,(6) Heavy Sg dirty water residue and iron heavy Sg residue cons, ?? heavy Sg sludge.

So with some practice I will have to be ready for alot of cons,in short bursts, the tender truck will remove the cons drums to a short distance and stock pile, , where they will be transported to a local secure location for final processing,

Point of interest here is the drums will be sealed before leaving the wash plant,

More on that asap,

Another reason for drums is, sorry gotta put this here to remind me for next post,



:smile:

dredger
23:19:17 Wed
Mar 16 2011
Re: Dredging w/Hydraulic Excavator
Back asap. for sure.

cmoelcmoecom
02:15:48 Fri
Mar 25 2011
Re: Dredging w/Hydraulic Excavator
kaveman
got access to ca. claim for rec. mining.
how much is too much to qualify for recreational
operation?
cmoe

kaveman
22:00:30 Fri
Mar 25 2011
Re: Dredging w/Hydraulic Excavator
Sorry, I don't know anything about recreational mining nor do I accept that such a thing exists. You're either mining or you're not mining IMHO.

cmoelcmoecom
22:40:10 Sat
Mar 26 2011
Re: Dredging w/Hydraulic Excavator
point well taken.
cmoe

dredger
01:52:23 Sun
Apr 10 2011
Re: Dredging w/Hydraulic Excavator
Drums of cons will be sealed and transported for further processing,

Ok, Just a few suggestions and pics on my back –up recovery concept for “ dredging with 2 excavators “ this is a small prototype concentrator , the line of thought is having several different recovery systems build ready to be changed over if the first concept fails, this is my line of thought , ,
Please note some points of interest,

1, this is a concept that is still in manufacture stage , absolutely no actually testing has been carried out, the line of thought is “ if the concept “, works, it can be duplicated to big enough cope with high production,
2. I would expect some very fine silt be caught in the lower storage areas, meaning I would expect a dirty concentrate in the bucket,
3, the concept is suggested and hoped to improve on the Popandson mat and mesh concepts by improving or hope fully improving gold storage capacity, of above concepts, New guys please note , I would suggest the easiest way of setting up ya first river or what ever sluice is to consult the Popandson guidelines, it is a tried and proven , with easy to follow guidelines.
4, further suggested that the “increasing the gold storage areas “ in small concentrators up to ?? 8” suction dredge, regardless of what ever mesh and matting you are using, perhaps even with riffles that use mating for gold storage, could should increase gold recovery as well as time in-between clean out,
5, this mechanism, has several different possibilities, or capabilities,
A, to increase gold storage areas at will , quickly and easily , GRADUALLY , increasing gold recovery, and time between clean outs, the scenario could be working a small high banker, and every ??? 20 minutes, you increase the volume of storage area matting to drop the heavies already caught in the matting, deeper into the matting. And present more open storage area,
B, is the line of thought that suggest if it is possible to increase the storage area at will it may be possible to decrease the storage as well, so creating a situation where the matting in constantly live, and moving, on a very miniature scale, the line of thought here is the moving matting gold storage area will keep it and the cons moving as well,perhaps nearly fluid. with in and below the live sorting area caused by the or a vortex , hopefully creating a situation where the matting is live, and causing heavies to settle deeper into live matting, and “ lift lighter Sg cons back up through ( displace )in the matting to the live crescent under the vortex, and be rejected, constantly,
C, as a result of compression and de-compression of the matting, I would suggest an added bonus here is “ displacement of water “, so the matting is physically live and massaging gently the mating which is just sorting by Sg the cons with -in the matting, , and the matting is also subject to an adjustable “ lift and drop “ “ blow and suck “ water displacement from below, ( how and why with pics following ),





the above pics show small sponge with fine scorer material similar to stiff / hard miners moss, and patches of backed miners moss materials that i have removed the backing,

Other pic show small squares of different grades of expanded alloy mesh as well as perforated or punched sheet, the idea being , having as many variations of mesh and matting for testing, and fine tuning,.

testing ,



dredger
09:57:47 Wed
Apr 13 2011
Re: Dredging w/Hydraulic Excavator

Please note , following 2 pics are close - ups of the shaved backed miners moss, or plastic spaghetti weave matting found in household and industrial door mats, these are a more open weave, and would / could have more compression and ultimately more gold storage area,

First a close - up pic of the scorer / sponge pad, please note the white hair is approx 90 micron,


Next is very closed weave, plastic spagetti weave,

Then the thinner more open weave shaved from the backing,

please note the 90 micron hair in pics,

testing,



Here is a few pics of the compression arms fitted or pivoted by 2 holes in the sides of the box, ,

dredger
10:24:51 Wed
Apr 13 2011
Re: Dredging w/Hydraulic Excavator


Please note, the two arms are pulled together using a push bike brake grip handle, via a cable, and the brake handle has an adjustable screw, this allows me to compress the mating and sponges and hold them there, I had also planed to drill and tap a bolt into the handle to stop the sponge being over compressed, and keep the compressions from a fraction of a inch, to a 1/4 ", or what ever is required, with the view of on a larger scale electric eccentric mechanisms could be fitted,

Closer look at the arms,


testing,

dredger
10:39:52 Wed
Apr 13 2011
Re: Dredging w/Hydraulic Excavator
Next pic shows the sponge and open weave matting is compressed.


More blar blar coming, back asap. dredger,

Please also note, the mesh and matting are in small squares, the idea is there are 6 squares per lenght of each box, and or 12 sponges , ( all brought from the cheap shop, ),

Each of the 6 squares or compartments will be seperated by a thin plastic sheet, to stop gold dropping deeper into the matting storage area, and migrating down to the end of the box, :confused:.

dredger
02:05:20 Thu
Apr 14 2011
Re: Dredging w/Hydraulic Excavator
Please note the sponge is compressed to about half thickness,this is not an indication of where or what thickness to begin testing,

The line of thought here is I can simply compress the sponge more, or quickly release it a little, giving me good or many variations of compression for when the time comes to test, please note compressing the sponge will result in water being forced up through the layers of 1, matting, and 2, metal expanded mesh,3. the heavy cons and punched sheeting as shown in above pic,also please note the " brown colored expanded mesh " is pressed to a shape that i believe will direct water " bursts or squats " at an angle, so by turning the the brown fine expanded mesh around I would suggest I will be able direct the water pressure at about 45 degree angle either up or down the box, into and through the matting and expanded mesh, please note the line of thought is the compression stroke might only be 1/16" or maybe bigger or smaller, and may be a very slow or even fast compression, resulting in a strong or weak current or movement of water up and down through the layers of mesh and matting,

At this point I should mention that all this fine tuning and liquidizing of heavy Sg storage areas withiin the mating, ect, in my situation it is my intention to run screened 1mm or 1/25" and under materials , with a focus on recovering under screen size in 3 different type of under screen size categories, chunky , med , fine, using 3 separate boxes ,
.
testing.

peluk
01:27:59 Fri
Apr 15 2011
Re: Dredging w/Hydraulic Excavator
I've seen and thought about fluidized beds Dredger but this is all new.The problem is that the information/design concept may be missed by some and it is very novel.I would like to see this under a new heading that concentrates on this development.It is getting too far from the "Dredging w/Hydraulic Excavator".It is an design concept that can be used by onshore equipment as well.

I'd even look at the possibility of just hardware cloth over the moss rather than the expanded metal.That way,if you threw flatter specimens up with the pulsing,they would settle back more readily in a flatter flow.If there were a tumbling action overhead,it might pick up those flat specimens and carry them further.
I know there are people here on the beach that use moss over carpet alone but it packs up and requires flushing often.This pulsing,if not too robust,might be just the ticket to a richer concentrate.You could leave the mats in longer.

I am no longer going to use my Proline Big Bankers for recovering large and small specimen gold.I'm going to use them for screening and washplant duty,capture the -1/8" or even -1/16" outflow in tubs and set it aside.Then,I'll work it at a speed and flow appropriate to small specimen recovery.
The old saying that you should move more material if you want more gold makes sense.It only makes sense however if you are doing so because there's not a lot of gold in your material to begin with.You don't want use that method to compensate for losses.

Here's a concept that may be being missed by the mining community.Ebay sales should be a clue.Upgrading material by removing a larger portion of the waste,makes it a saleable item as is.That means,a lot of the coastal deposit here for example could be shipped out as valuable ore in the form of fines for someone else to work.It would be prepped in other words but the man hours to bring it to a finished product would not be expended here.It could go out on barges....or crates.

I knew this would get away from us but your idea looks good to me.It looks like an improvement on a jig.

dredger
09:00:16 Fri
Apr 15 2011
Re: Dredging w/Hydraulic Excavator
" you say " I've seen and thought about fluidized beds Dredger but this is all new.The problem is that the information/design concept may be missed by some and it is very novel.I would like to see this under a new heading that concentrates on this development.It is getting too far from the "Dredging w/Hydraulic Excavator".It is an design concept that can be used by onshore equipment as well.

dddddddddddd I agree Peluk, I am sure just about any sluice any where or on anything could be easerly and quickly fitted with compression arms, riffles or mesh or what ever, I am sure it would have been of benefit on my 8" dredge,wish i had of thought of it then, haha. and yes I had thought of a new thread when i finally get time to do some testing, for which i need a fresh batch of cons, and new camera, and as this concept is the back-up for a totally different concept for dredging with a excavator, if the first concept does not work , plus I have been working on these boxes for too long, plus the fact I have had one beaut car accident, I just had to before another car gets me, haha,

I'd even look at the possibility of just hardware cloth over the moss rather than the expanded metal.That way,if you threw flatter specimens up with the pulsing,they would settle back more readily in a flatter flow.If there were a tumbling action overhead,it might pick up those flat specimens and carry them further.

dddddddddd, yes, I hear what you are saying, and was thinking,the compression stroke could be relative to the height of the mesh or riffle,or more to the point the height of the working vortex, and tune the stroke height and energy to basically only displace or momentary fluidize the materials at and in the sorting area, at the base of the vortex, so at a guess I would suggest the compression stroke be less then 1/4 to 1/2 distance to the mesh /riffle height being used, my line of thought is Randy Clarkson said that bed armoring would could occur or start occurring with in 12 mins in a riffle at the start of dredging, My experience is that when I start running my dredge, on occasions have had another dredge dredging my tailings, and I have found that in this triple sluice,

Which completely packed up in about an hour, and started loosing gold,
For the new guys my drift on that is natural Armour bedding or bed armoring is when gravels pass or washed over a gravel bed or bar, the flow of the water (start of a flood ), , places finer smaller gravels in between larger rocks, and creates a very hard smooth layer of finely packed gravels, which do not really allow gold and heavy Sg metals to just fall through,in fact most gold will ride /skid, roll over this hard packed skin, Clarkson simulates the same or similar hard packing behind each riffles in sluices, so my focus is on just 1 possible use for this concept, right in and at the bottom of each and most all vortexes, mesh or riffle, ect, where the energy in the vortex scorers the top of the matting,and where the vortex can jamb or fall gold into the matting, and where the amour or had packed occurs, this where just a few short compression strokes with just enough energy to displace or lift the lighter packed Sg's materials only enough to present them to the base or bottom of the vortex, and defiantly as you say not lift them into the upper flows, I agree. ,


I know there are people here on the beach that use moss over carpet alone but it packs up and requires flushing often.This pulsing,if not too robust,might be just the ticket to a richer concentrate.You could leave the mats in longer.

dddddddd I agree,and Actually, this concept was inspired by Nome Beach samples, and yourself as well as many others on this forum, 3-4 years ago, may be we can call this concept,

" THE NOME SQUEEZE "
" THE ALASKAN COMPRESSOR ".

Mmmmmmmmmm, richer concentrate, could be better then $&#.( at our age ),

I am no longer going to use my Proline Big Bankers for recovering large and small specimen gold.I'm going to use them for screening and washplant duty,capture the -1/8" or even -1/16" outflow in tubs and set it aside.Then,I'll work it at a speed and flow appropriate to small specimen recovery.

dddddddd After seeing Kevins ?? tooth size chunky gold to day, I agree mate, keep working on those little chunkies,


The old saying that you should move more material if you want more gold makes sense.It only makes sense however if you are doing so because there's not a lot of gold in your material to begin with.You don't want use that method to compensate for losses.

Here's a concept that may be being missed by the mining community.Ebay sales should be a clue.Upgrading material by removing a larger portion of the waste,makes it a saleable item as is.That means,a lot of the coastal deposit here for example could be shipped out as valuable ore in the form of fines for someone else to work.It would be prepped in other words but the man hours to bring it to a finished product would not be expended here.It could go out on barges....or crates.

dddddddddddd Excellent idea Peluk, Nome Beach sands could be a president for testing concepts, considering the amounts and fineness of Nome Beach gold, and e-bay is a good clue, I like your idea, do it.

I knew this would get away from us but your idea looks good to me. It looks like an improvement on a jig.

dddddddd Thanks Peluk, incentive from such a connoisseur of fine gold like your self is very much appreciated and treasured , and if not an improvement on a jig, perhaps an improvement or open doorway into matting, ( we will never know, if we never go there ).

:smile:

dredger
09:29:47 Fri
Apr 15 2011
Re: Dredging w/Hydraulic Excavator
So the three " inline " boxes would start with the chunky gold under 1mm classification, , recovery, using only just enough energy generated by a " compression stroke ",to only retain chunky shaped gold,and reject as much as possable med and fine floaty shaped gold, ( larger expanded mesh, open weave matting, many layers of mating ,)

Into the middle or second inline sluice, smaller mesh and matting, less and slower compression stroke, slightly reduced box angle, with enough energy to still move the bulk of the fines into the third sluice,

The focus is to eject as much fine gold out of the first chunky gold storage area,first box, my line of thought and suggestion is that where fine and course gold are in the first stage of fluidized, the fine gold will get under the bigger gold, and lift the larger gold,,

A test scenario might be to load the the first box with screened chunky under 1mm gold, then run fine gold, I would suggest after some time the finest gold would work it's way under the larger gold, especially in or if the matting and gold storage area, is alive and moving, (gently) all or most of the time,

I would also suggest " if " this concept works, after alot of testing,the end result will be increased gold storage, longer time between cleans outs , and less percentage black sands to gold percentage in the cons at the end of the day, or experienced with a standard non-compression, while still having the labour / time required to dissemble clean and reassemble mesh/ matting,

Back asap.


dredger
06:06:18 Tue
Apr 19 2011
Re: Dredging w/Hydraulic Excavator
Yep ,lost another one,:confused:.

So, from the start, again, the line of thought is to develop a concept, that can be used differently in different situations, mainly because the mechanism ( compression arms ) is greatly variable, matting and mesh sizes,

Concept being, compression of the matting, and sponge, to " liven -up " the matting ", ( hopefully to settle the heavier Sg's ) and with a " accurately adjusted " ( stroke and rate of compression )on the sponge to force water " up " through the matting to help lighter Sg's be represented to the base of the vortex, and ejected,

First possible application, simply use the concept,just a few gentle compressions to settle the heavies, at the end of a batch, and before clean out,to basically and gently float off the dirty water and silt,
Second , is to use the compressions of a few compressions to settle the heavies in the matting, say, every 10 mins during the day, or half days work,to keep settling the heavies in to the matting,
Third is to use the compressions full time, or while your are run materials,

Please note , the line of thought is those compressions strokes are ( guessing, ) 1/4 the height of the the thickness of the mesh and matting,

Now changing the compression concept to a different situation, not a flowing sluice, with a flow of water carring the gravels, not that,

Using the same box, to process " wet milled or wet classified gravels ", wet like freshly mixed cement,

In this application,The box is " level ", the compression stroke and energy is increased, the stroke is ( guessing ) 1 and 1/4 the height of the mesh or riffle, ect, and the focus is the create a strong " fluid bed in the matting and just above the mesh or riffle level " , please note , all crushed / milled or river cons are classified,and the classification is relative to the height of mesh, ( thickness of matting, would be relative to how many hours of processing is required,). and further " stroke and energy tuning could be requried as the heavies build up in the storage areas,/ mating,
The scenario could be, three boxes in line and laying flat, the first box, is meter feed with a wet cement consistency, the "inlet " or beginning of the box is blocked and the meter feed slurry just builds up as it is affected by the strong Fluid bed, ( please note, the pulsing water squeezed from the sponge as it compresses,or is compressed, )will lift or fluidized the layer water and materials, on and above the mesh, ), please note again, the water being displaced due to the compression will be directed vertical, please also note with use of a particular expanded mesh in the above pics, the vertical force of water can be learned forward , or backward to the flow, the line of thought here is if the compressed water flow is directed towards the out let of the box, It may cause the lighter Sg's to move fast towards the rear of the boxs,
Another option my be over the length of the one box, or over the 6 separate mesh and matting square sections in each of the 3 boxes, (18 square section in total,). It may be interesting to use the directional mesh to test different ideas,
1, to direct lighter Sg's out of the box, quickly or at a rate of production that is viable,
2, to direct the fluidity back up the flow, so the when the box angle is increased from level to a few degrees , the direction of the fluidity again becomes vertical, while the box is on a slight angle, which may be the key to good flow and production through the box,????,
3, is perhaps to alternate each section to flow towards the outlet, next section is reversed,
4, perhaps it may be worth testing on or in a tilted back box, and increased compression forces, ??. but I think it is worth testing if not to just prove there is no advantage, ,

Oh Yes again, my line of thought is " fluidity " is at all times a fine tuned compression and energy / mechanism, focused on the separation of heavy bulky fat chunkiest Sg's from all other lighter Sg materials, while maintaining a low pertange black sands in the mechanism " in the first box, each 6 separate sections of gold storage, are tuned to retain heavy chunkier and reject flat flaky , and fine gold,black sands ect, to the second box, the second box is tuned to handle reject black sands and fines, and retain flat flakes small chunkiest, third box is tuned to again rejects black sands and hopefully recover all fine gold,

Please also note, the above boxes are a scaled down proto type concept that I hope i can scale up to large enough to handle dredging with a excavator mobile wash plant,, also please note, the above size screens , meshes and mats would be used for a under 1/25" screened materials, it would be my intention to process or sluice all 1/25" up to 1/8" washed gravels in a slightly scaled up in size mesh and matting sizes, as well as slightly wider box, and slightly more energy,deeper water, ect, and again scaling up for 1/8" to 1/2" screened gravels, and up again to 1/2" to 3/4", multideck sluices for bulk sluicing situation is required,

Next would be cleaning or the quickest way to disassemble , clean the mats, and reassemble, of which i have few ideas, and the reason why this concept is second choice primy processing unit for the dredging with a excavator ,,first choice coming soon,few ideas and a few pics,

Also, I was thinking, about , ?? how many options there might be when fitting the sponges matting and mesh layers, I could start with the standard metal mesh layer on top of say miners moss layer or layers, and on top of the sponges,

Or I could test several layers of metal mesh to create a deeper hole in the mesh, resulting in a deeper vortex and distance to the matting for that mesh size, and I suggest that compressing and releasing several layers of mesh, would resulting in the or each alloy mesh layer moving in relation too each other , and hopefully creating moving peripheral case for the vortex to form, and maintain that energy constantly, and over the operating period, , and not allow any packing up ,perhaps several layers of matting for a large gold storage, and the sponges, ??. just ideas.

Another test might be several layers of mesh, and no matting except the fine matting attached to the sponge /scourer material, to do small batches of cons, and cut down the percent of black sands, when doing small batches of cons, ?? ,
back soon,.

peluk
17:36:14 Tue
Apr 19 2011
Re: Dredging w/Hydraulic Excavator
Here are some thoughs on your concept,Phil....
1)Often the idea of vibration in a sluice is suggested as a way of getting heavy specimen gold to settle or even small specimen gold.I think it merely packs the sluicebed.This sponge layer and moss and screen guard w/compression arms would be the way to lossen the bed of black sand and garnet.This looks promising.
2)Will the sponge layer be able to be flushed of fine gold thorougly?I don't have any handy but I wonder,would manufactured sponge burn to an ash capable of panning at season's end....or does it melt into a blob?

3)Reflecting on your optional layer of stacked screens on the moss, over a sponge bed in a smoother flow...I wondered about weak points in the idea.One would be the joint between sponge sections.They could be cut to interlock as in siding strakes(house construction).The side of the sponge against the sluice wall would depress inward with the compression stroke.It could be cut with an interference fit to compensate.
4)Now that you've mentioned the tentative timelapse between compression strokes,I see there is a span.I see as a possible alternative this possibility, especially since the compression device is complex.
The sluice bed would be bounced by an eccentric device.Suspended just off the screens would be a weighted screen with downward protruding bridge spike heads.The sluicebed would be bounced by the eccentric and the spike heads would punch the screen surface as it comes up to meet them.The sponge bed would send a pulse up and your action would be mimicked,with a slight variation.
In a simpler form,the bed could have weights on the screens but you'ld have to be able to get them to bounce.That would be a task.

Generally,for me,I see the sponge base with its capability to induce a pulse through the bedding as the major feature of your idea...no matter how it is achieved.

This could be tested with blacksand and silt to see how it flushes to begin with.This problem has puzzled me and your idea is very exciting.

dredger
11:25:07 Wed
Apr 20 2011
Re: Dredging w/Hydraulic Excavator
( 1 )Very interesting, and I agree vibration or a constant vibration as well as the natural phenomena of Armour bedding quickly increases packing,and of course the gold rolls or skids right over packed gravels, however another thought might be a intermittent shock wave,but an low energy shock wave would be quickly adsorbed in wet gravels, :confused:.
I like the word loosen alot,, rather then fluidized, if the gravels are loose or loosened, the gold will keep falling, loosenized, loosening, ?? someone should chisel that on a stone somewhere,
( 2 ) yes the sponge looks good, fines will get into the matting scorer part, and the sponge really only likes water ,so no fines really get right into the sponge, my line of thought is to flush the scorer matting is to place it scourer side down in a pan and just compress the sponge a few times, it appears the the water fills the sponge when submersed, when I compress the sponge with my hand, forcing the water down and through the scorer matting, blasting anything in the matting into and on to the pan base, I am thinking or remembering that they would not be a problem until they got real old maybe then they might be worth burning, I am unsure of the abrasive material attached to the fine matting, but the fine scorer matting is plastic,
here isa pic,

Again the hair is about 90 micron, so the plastic scorer matting could be about 60 micron, and yes melted plastic blobs do burn away slowly, so burning a sponge I think you might end up with a lot of black soot, and some fine scorer grit at about 7 Sg, for your interest I use sponges when cleaning or basically sucking the water away in the front section of the boxes, basically if there was fine gold there, I did transfer any last b/s and the gold by sucking onto the sponge,then straight in a pan full of water,couple of squeezes and back for the next lot, it was not so much the picking up of the gold, it was get all the grit out so I could get the riffle rack back in, easier, also I think my backed open weave sapgeti matting is easy to clean then miners moss, since I cut / scraped the solid/ thick plastic backing off, it is really no trouble to wash, another something that might interest you was as the gold dropped through the screen, and was split to the top of the side boxes, the flow was fast, and occasionally left some pickers when I shut down the dredge, sometimes ya could see pickers moving slowly, so I used or rubbed the alloy floor of the sluice in the picker path with the scorer at a off 45 degree angle to the flow, which sort of directed the pickers or a lot of pickers out of the main flow, sort of a party trick, but it was nice to see some nice clean ( no b/s )pickers piled up when shutting down the dredge,??. or running clean water.

( 3 ) Ok, the joint in between the sponges, or the 2 sponges in each of the 6 separate sections, for each box, I thought i would cut lengths of a thicker plastic bag, or plastic off a shirt box, then heat to fold square so each short length, 1 sponge long, and the depth of the sponge matting ,and short vertical end layed on the back of the previous section, and along and under the sponge, to basically stop gold traveling between the or each sections with a vertical thin plastic sheet, I am thinking a stiff plastic sheet would stay tight enough not let gold travel between gold storage sections,and you are right, stopping the gold what ever size from migrating to the end of the box, and into the next box is a critical factor in the concept,
I thought the sponge expands under compression and would rub more on the box wall, ??. and I would also suggest that the new guys please note, my line of thought is in a jig situation, the surface of the flow, is usually choppy , and rough, due to the water displacement or jigging action,, where I believe with this concept, the surface of the flow should be relatively smooth,and relative to the depth and height of the mesh / riffle, and not choppy, due to the fact the matting and mesh are compressed up and down through the water, at a lower level then the flowing surface, meaning, the water level running through the sluice will not rise or fall with each or any compression stroke,, whooo, :confused:
( 4 ) I hear what your are saying with a punch, but punch means or could mean knock out, and I want to go with what you said before, Loosen , so I am thinking " gentle massage loose " to keep the gravels in the live sorting cresent at the bottom of the vortex, and the gravels in the matting very loose, with a slow massage, and slow short stroke, with a or the right compression energy to compress the the water in the sponge,up though the 1, scorer matting,2 some or several layer of matting, with a up lifting force,to or that clearly and accurately targets below and above 12 Sg, and basically has enough force to lift or keep loose gravels ( highly classified ), with a low Sg, and not really Hinda High Sg materials from settling,
Also please note, I am referring to this concept, which is really all about classification, and the or my theory of the / a vortex, as a specific gravity separator, V= D/a, or vortex = diameter / acceleration, which i suggests leaves out the very relevant bits about size or classification,being relevant to the diameter and acceleration of the vortex,to "expect maximum accuracy possible" to start with, which then is very relevant to the last part of the this concept, Compressor ,The distance of the stroke, and the energy required to gently lift just a little lighter Sg materials,at the base of the vortex, (prevent packing,) but not enough energy or lift to hinda heavy Sg materials from settling down further into matting gold storage areas, which are also continually alive, or even perhaps only come alive for a few compressions every ?? 5 or 10 mins, BUT, PLEASE NOTE,

Sorry mate, back asap,phil.

Ps, I will leave the below words to remind me to finish what I was saying,


The above box has been reclassified, which means I have had time to think about previous

peluk
18:41:20 Wed
Apr 20 2011
Re: Dredging w/Hydraulic Excavator
Corrections noted,dredger.I forgot the scouring layer on the sponge.Whether the sides of the sponge that butt against the sluice force outward or bend inward at the top edge can be observed in a dry run in the R&D stage.

I'll watch it develop.

dredger
23:49:53 Sun
Apr 24 2011
Re: Dredging w/Hydraulic Excavator
Hey Peluk, thanks for reminding me I left out a few thoughts and pic,,



The above pic shows hair laying on 90 micron stainless mesh, my line of thought is use perhaps a 20 micron stainless mesh on top of the scourer material,or just 20 micron mesh on top of the sponge materials, no scourer material, and or to really restrict the size of silt that can get below the matting, and into the sponge, and building up,I am still looking for fine perforated material like thin metal or thin plastic perforated sheeting too.to test, again I think even 20 micron wire mesh would have or allow good water flow, and restrict fine b/s from passing / falling into the sponge, I am glad you picked up on that mate, thanks, .

Please note, if the concept or part of the concept is to accurately increase the gold store area in the matting by periodically releasing the overall tension on the over all compressor arms, ( while still maintain the same compressor stroke, )I am guessing to start testing, the compressor stroke might be 1/16 " and to increase gold storage area in the matting, adjust over all arm mechanism UP say 1/4 to 1/2" , ??, something like that, leave both restriction bolts the same distance, then adjust both or one of the screw adjustors on the cable, which will basically just raise the the mesh layer and although more room in the matting,also please note the above pics compressor mechanism has one adjustment screw integrated or molded into the handle, it was my intention to drill and fit another screw to accurately restrict to travel of the handle, that would be the 2 compression stroke travel restrictions, and the 2 other adjustable screw on the CABLE are the height control, plenty of adjustment in both,

I agree the ? seal from the sponge to the box wall should be tight, less gaps ,less silt, so I will make a note,good advise, here , " all future prototype sponges should be wider then the box, and squeezed in to provide a tight seal ", ohh, speaking of seals it was mt intention to fit a say 1/4 beveled plastic C channel "around " each mesh sheet,plastic weld the 4 corners,fiddly but might be worth it for a good seal,and slid, i hope,also another thought is a plastic beveled edge, may cause a gap in between layers of mesh, the gap would be squeezed and flexed with each compression and hopefully gently cause the heavies to settle and displace lighter materials,

Sorry mate.gotta run, back asap, phill/

dredger
22:22:02 Sun
May 15 2011
Re: Dredging w/Hydraulic Excavator
Bump. excycling new idea cooking, back, asap. dredger.:smile:.

dredger
05:08:15 Thu
Jun 9 2011
Re: Dredging w/Hydraulic Excavator
Sorry that idea developed a snag, that I just can't think of a solution, I have been exceptional busy, in toooo deep actually, :smile:.

Never the less, I am trying to do some sketches to explain the snag, I really do want to develop this concept, because it will be a a lot quicker to clean the matting, in fact it will be auto cleaning, as opposed to cleaning to many sq feet of matting, used in the previous compressor concept,

Any way, I will try to get some sketches and pics to show the " snag " , Sorry, back asap.

dredger
22:20:03 Fri
Jun 10 2011
Re: Dredging w/Hydraulic Excavator
Just thinking out aloud, and in circles.

The previous " compressor " concept, I wish I had on my last 8" dredge, " side boxes ", and if i ever set up another 8" dredge with a classifying screen again, I will use that concept, to keep the matting just fluid to maximize gold storage capacity., and I was looking, well actually finding "all" the boxes pictured above, so maybe I might get a chance to test it, ??.

My focus remains on a basically water flowing sluice,? table, that I will not have to worry about cleaning matting ect,

Please note, matting used as a gold storage device, has to be remove, cleaned and replaced, and my focus is high speed materials handling, requiring, ( don't worry I am just talking " my self " into this, ),and it is getting complicated, ), a automatic cleaning factor, so, no matting, but still using the or a vortex and small gold storage area, as the main concept gravity separator,or V= D/A, ( Vortex = Diameter / Acceleration, Acceleration meaning the velocity of the water spinning in the vortex, and also always relative is my line of thought, is V = D/A is always relative to the classification " size " of the pay gravels sands, meaning to me, the smaller the classification, the smaller and less energy the vortex should be required, but still not forgetting that " overloading " of Black sands, will effect the velocity of the spinning water, vortex, I would suggest small % of BS would effect the velocity in some way, and over loading with BS would effect the velocity in a greater way, as well as the over all amount of gold per cubic yd being processed in each cu yd,

As well, there is high speed materials handling factor 2-3 x 30 ton excavators and a mobile processing unit ( floor space 3 x 40 foot containers, ) plus, so far my line thought is " not so much " the target number of cu yds per hour, but how many seconds I can maintain 1 cub yd Per second, meaning, 1 cu yd of materials would be forced into the mobile processing unit, the unit may have a say around 30 cu yd capacity, ( suggesting high speed or quick classification 9 seconds, and sluicing, 17 seconds, 3-4 seconds to extrude or eject processed materials), resulting in many cu yds of processed concentrates would have to be removed from the processing unit per hour, while moving,

And back on subject, many cu yds being sluiced over a large area of many sluices, for each classification, in ?? 17 seconds, suggesting some points of interest, 1 , being the length of sluice will be relative to the angle and velocity of flow for each classification,

Sorry to late, and tired,will post , back asap,

Ps, reminder to me, Auto cleaning factor, and reducing sluice surface area required, with auto cleaning factor,for each classification, and the idea that tuning the auto cleaning factor to the gold present in the or any particular area may further reduce the total Sq or area of sluice required,

Also hold thought for near future clarification, on the second hand movement on a watch face, focus on the hand moves from one point to another, every second, 60 points at which the arm stops each for one second, then moves to the next point,

:confused::devil::smile:

Hope everyone is having a good day,

dredger
23:24:18 Mon
Jun 20 2011
Re: Dredging w/Hydraulic Excavator
Sorry , I am nearly dead, but not quite,

Back ASAP, dredger.

Ps, Swiss coming down under, - Oct -Dec, let the good times roll.

Psss, oooh, Son,s Wedding around then,??.:confused:.

dredger
15:00:57 Thu
Jun 30 2011
Re: Dredging w/Hydraulic Excavator
Ok, sorry bussy as, Can not help it , and perhaps I will be off line, 3-6 months, July 7, ??.

Auto cleaning, and the movement of a second hand on a watch face, ??, well the watch face is relitive to the rotation,or direction of the conveyor belt, meaning a conveyor type set of riffles, please imagine, a sluice, with riffles,working with water / gravels flowing down, and the riffles move back down the sluice, as if and because the riffles travel as part of a conveyor belt, concept, the line of thought is as the conveyor riffles or vortexes move back down the sluice, and reach the end or specifically just before the end of the conveyor / riffle section, there will be a gap, where the concerntrated cons recovered in the riffle / vortex / gold storage area, would drop through the gap, into and out of the flow. gold storage tanks and be transported, as gold, with the minimum none gold gravels " percentage ", so if the gold percentage in the gravels ( per square yard are low ) the conveyor riffles travel slow to ensure the vortex and gold storage are basically full of gold before they reach the gap, and drop out, if the gold in the gravels is a high percentage, the speed at which the riffles /gold storage areas move is increased,perhaps the speed of the riffles/ vortex /gold storage could or might increase and decrease as the excavators dig from left to right, of the gold run,

So the line of thought is , gravels / gold , all and only chunky or fat , say, 1 mm to 3 mm, or 1/25" to 3/25", no under 1mm, grit or dirty water, no flat flaky , focus is chunky and fat, riffle or conveyor section /lenght say about 10 feet, maybe 3 feet wide, at first guess, inbuilt 6" or maybe less, 3" wide/long slick plate deck, suggesting 20 to 40 riffles exposed to the flow over or along 10 feet lenght,each moving back down the sluice /flow,toward the gap, so by adjusting or tuning the speed of the conveyor riffles,moving to the back or down the sluice,will give control over the percentage of the gold / none gold gravels that drop through the gap,

Another consideration is when the run, of gold, stops or jumps, and there is no or very little gold percentage, the conveyor or speed of the conveyor should stop. food for thought.

I like this line of thought, please note, 1am and very sleepy, will ponder more,

Note to self, water filter or high velocity particule seperator, inline, not relivent to the flow velocity.stop / start, ??, back asap.:confused:.:smile:'


dredger
14:01:29 Thu
Jul 7 2011
Re: Dredging w/Hydraulic Excavator
Ok, Photobucket will not let me copy and paste, and I am not sure if they will let me put sketches up. either.??. and i am still busted for time, and 7 July moves to 29 july, maybe take a rest from it all. ???.

So the thinking out loud has moved from a conveyor line of thinking, to a back ward / forward motion, still has a slick plate in front of and behind each riffle / vortex /Au storage area,at this point i tried to post some of my old red sluice pictures, , and specifications and some further info, but photobucket will not co-operate, so I will refer to a stand back eye view of a sluice,so imaging a 10 foot long section of a 30 foot long sluice, I remove the 10 foot long right angle riffle rack, and sweep the floor of the box clean, then place boards across the flow, I use say ??, a 36 mm gap, ( 1" and 11/25", )the gravel classication is 1-3mm ( 1/25 - 3/25". ) gold gravel, no under 1mm,already has been classified out,
{{{ Ok, my formular / best guess for the gap or distance between the front slick plate and rear slick plate is 12 times the size of the classification,
under 1mm or 1/25" classifcation gravels is mulitiply by 12, = 12mm or 12/25",gap between slick plates,
1-3mm class gravels is x 12 = 36mm or 1 and 11/25". gap between slick plates,
3-8mm class gravels is x 12 = 96mm gap between slick plates,
The line of thought is to only sluice 1- 14mm classified gravels, each classification having larger and larger gaps and specifications,}}}
Please note, 2 relivant points here, 1, being please do not forget I am trying to crame in a cub metre per second into the processing unit, ,meaning maybe 1/4 - 1/2 cub meter of gravels with in the above classications of gravels have to be sluiced ,possable solution being the " new " back / forward motion, concept ,line of thought, ( new ), basically, yesterday,

So back to laying say 3" wide x 1" boards, across the flow ,in the sluice box. where the original rack of riffles lay, I say boards because wood or fine grain wood would suffice for testing, and hard wearing plastics or metal for high production, the boards / slick plate would wear quickly considering the joke about 1 cub meter per second, Guidline,
So the cross flow board sections are gapped at 36mm, and attached to each other, and able to move / slid backward say about 1/2", slowly, the line of thought here is the heavies laying in the gold storage area, will be slowly pushed back and forth to increase gold settling possabilties, and supposing that works, there could be a suggestion of increasing the back forth motion, ??
:confused:
might actually settle or sort the heavies ?? quickly, in the gold storage area,by basically rolling, ?? or pushing the cons over the floor of the box, again supposing that works,and supposing after much testing, and due to a few other factors, I can fairly accuratly know, when , or calculated when that gold storage area was full or perhaps 75 percent gold,25 percent B/S, I could then pull the slick plates back a further 3/4 " and place the gold storage areas over slots cut into the floor of the box, the heavy cons / gold drop through as well as being flushed through the slot and drop into manifolds, and piped or screwed away, and the slick plates move forward, and close /seal the slot, imediatly begining the slow back forwad motion, ?.

Sorry gotta sleep back as asap, as I can ,

dredger
13:32:36 Tue
Jul 12 2011
Re: Dredging w/Hydraulic Excavator
Ok. supposing that works,

I will need a way to know when the storage areas are high % gold small % black sands,

So please check out the previouse page and note the diagram showing a shaking chute feeder with water blowing the lighter Sg gravels off the heavier Sg gold, also please note I forgot to explain the figures 6-7-8 in that sketch, ( Sorry about that, )

No6 is a camera, directed on to the exposed gold,
No 7 is or a computer receiving the pictures,
No 8 is a light on a light board, that will grow brighter when when or as more gold became visiable, the line of thought is a camera for each shaking chute, for each classication,about 5 cameras and glowing lights mounted in the operators cabin, hope fully this will aid the operator in knowing roughly how much gold and what classifcation he is actually load and sucking into the processing unit, as he works across the run,

Also, I am thinking if that works, just supposing that works, , I might be able to programe the computer, to empty the gold storage areas as well as glowing a light, ??. :confused:.

So guessing that works the or a scenerio could be, the camera sees most of the gold,as it passes/shakes it's way down the shaking chute, and storage areas are close to full. calculates how much gold it sees, and knows when to pull back and empty the storage area, again if that might work, I can further b/s and suggest this would greatly reduce the surface area of the sluice, ect, maybe empty , and see and know when to empty the gold storage areas, quickly, maybe every 2 minuties, or 8 minuties, maybe the total gold storage area, could be a thousand grams, and take 4 mins to recover, concerntrate, and clean the gold storage areas,, ??. and requier only a small surface area compared to mat and mesh recovery, just guessing and thinking outloud,

I hope to discuss the camera / programmed computer ideas with someone very special, in 3 days,??. and 12 hours drive, LOL.
Back asap.

dredger
01:29:23 Tue
Jul 19 2011
Re: Dredging w/Hydraulic Excavator
Done it. back asap, dredger.

eightymesh
16:22:49 Tue
Jul 19 2011
Re: Dredging w/Hydraulic Excavator
just a thought

first off take a look at these scales they would occilate much like a fishing spoon in the flow and with the crowned shape would self clean allowing heavies to crawl back under leaf to the sponge





one source for scales and chainmail

caution: there are damsels

http://theringlord.com/cart/shopdisplayproducts.asp?id=84&cat=Scalemail+Supplies&websess=52356585316066

one more brain fart was either using fire place curtain or chain mail




:devil:

dredger
13:30:31 Sat
Jul 23 2011
Re: Dredging w/Hydraulic Excavator

Very interesting Eightymesh, very, scales ontop of chain mesh,sponge,??.
occilating,my line of thought is the gravels should classified and only under 1 mm, supercons, maybe a clean up sluice table, ??. larger gold might not slid back under, again just guessing,but iI like the idea. occilate the scales differently to the chain mail, perhaps resulting in a fluid gold storage areas, between the scales and the sponge.??.

The occilation might loose effect after perhaps the 3 rd row of scales due to b/s build. perhaps not,?.perhaps every 3 rows of scales would have to be occilated independently, ?.

Water flow may have to be slow, ( no vortex action required ?).

Scales appear to me to be concave, ?, but i have old eyes,

Ok got back from trip and as soon as I got there wireless usb crocked it, so I cannot show links,( I am on a friends computer) but did have discussion concerning programming a computer/camera to 1, recognize a moving run of gold, ( shaker feeder ) and determine if there is allot , or very little, and glow light to show how much, 2, program computer to record the flow or run of gold. And clean/open gold storage areas, according to total amount of gold passed in front of the camera / computer, for each classification,

Now, sticking point here is i am focusing on 1 say 2-3mm classification, and a recovery vortex concept that is or has a high vortex velocity, and targets only chunky fat gold of the above classification, all fine and or flaky are rejected, and move down the flow /sluice to their own recovery section, and the sticking point here is that this high vortex velocity concept with the back forth motion gold storage areas that enhance further sorting and concentrating with in the gold storage areas, suggesting that the number of vortex/ riffles could be reduced to one, and that gold storage area, be cleaned every few, ?? 5 seconds or 10 seconds, then concern is overloading more then one storage area, in order to allow more gold to more further down to the next riffle, that is provided the high velocity vortex concept is 100 percent effective, ????> have to think about that some more,

If that works, ?,, please note, there would be around 5-6 classifications, 5-6 shaker feeders, cameras, glowing lights and, independently operating cleaning/opening gold storage areas, for each 5-6 classifications /sluices, if that could work, :smile:

By this time, the two 30 ton excavators would have been modified / and act in a much faster and more force, then the standard, a bit stronger in the actual digging and filling the bucket and alot faster in moving the bucket to the hopper and back to digging position, so , so production should also increase,??,

Sorry back asap,


dredger
23:13:09 Tue
Aug 16 2011
Re: Dredging w/Hydraulic Excavator
I am trying, bussy as. back asap.:smile:

dredger
13:10:56 Mon
Sep 26 2011
Re: Dredging w/Hydraulic Excavator
So, the line of thought is to extract a good concentrated con, as the gold storage areas fills with gold, please note,by concertrated con, I surpose I would mean ? say %50 gold and %50 b/s, with a focus on extraction of cons, or emptying the gold storage area as it reaches 50/50 cons,( with tuning, I hope maybe 80/20, who knows yet what a camera and a computer can do, ??.)
Now to try and guess the total gold storage areas required, total sluice surface area, I would suggest 2 factors, first the above and it ability to extract or drop the cons quickly, ( still guessing,) say the storage areas could be emptied in or at intervals of say 5 minuties, down and to say ? 10 secs, that will be up to the computer,so the whole operation is finely tuned, and production ( at times ) is 1 cu yrd per second, ( in short bursts, ) of 10secs to 20 mins to :confused: depending on the gravel beds, ( for the new guys at this point, the thought that river gravel beds are soft easy digging if there are not too many big rocks, ), so in a 10 sec burst hopefully aound 10 cu yds of good paying gold run gravels are recovered, at say average 3 grams to the cub yrd,average, in a scenario 3 gram per cub yrd location,suggesting a 30 gram gold 30 grams ( roughly ) b/s, suggest 60 gram cons storage required, that can drop the whole storge in 10 secs, guessing, dreaming, over 5-6 sluices with each classication, a point here is the gold storage areas would be dropped into a large storage tank or container, so the frequency at which the storage areas are emptyed can be very quick, the storage tank or container would be monitored by the computer,

Note to self, on an attempt at a concept of " high speed screening ", 5-6 screens, a drawing would be great, except that I do not currently have time, but the picture in my head looks good.:smile:basically 2 moving parts, and very variable, and a RPM RANGE OF ABOUT 10 either way, clock wise and ant-clockwise, hope i can come up with a quick way of explaining concept soon,back asap,:smile:

Put a smile on ya dial.


dredger
00:59:53 Thu
Oct 20 2011
Re: Dredging w/Hydraulic Excavator
Ok please note, a VERY rough sketch , contains no sketches of feeders ,hopper, mounting points, ect. upper left, TROMMEL BAR SCREEN, 15’lenth x 18” id dia , is basically a flat grizzly screen as we know it , rolled or built , into a revolving trommel concept, and rotates ( screen gaps sizes, Perghaps 1” x 15’long, down to 2/25”x15’long ) about 5 trommel grizz bar screens in total, so this T B S concepts focuses on under 1” gravels, already classified down to 1”, all over size size say 1” will be classified and processed dry/wet, No sluice, and fine silt, muddy water, light Sg materials will be washed “ off “ before gravels enter the TBS screens, hopefully .
Middle right is an “ orga “, ( large post hole digger type orga ) perhaps around 17” ? 16” od dia, the orga is around 15’ in length, The idea is THE FLAT GRIZZLY SCREEN CONCEPT , IS rolled/built into the trommel bar screen concept, in the hope that revolving the screen will present ?? “ more clean or cleaned screen gaps to the gravels, with an option and suggestion to speed up the presentation, also possibilty
The idea of the orga, is, 1, force / push/pull. gravels or rocks that may jamb in the screen gap,along the gap, ( 15’ )and out of the trommel.
2, is to control the velocity,speed / volume of the gravel travelling through the screen,
3, present more materials to the screen surface,
Please note the trommel bar screen will rotate, I would build it to turn clockwise and anti-clockwise, as well as the orga build to run clockwise and anti-clock wise,variable speed, 1-15rpm, guess,
As well as being fully adjustable angle on the trommel, ,5+ degree either way of level. as well as changing which end of the trommel the gravels enter and leave, ( under size hopper/manifold not shown in sketch.
The idea being to “tune “ the right angle, rpm, gravel flow direction, for the fastest classification, possible,,

Sorry, I can't get the sketch from photobucket,working on it, back asap, dredger.


dredger
04:51:42 Sat
Dec 17 2011
Re: Dredging w/Hydraulic Excavator


Finally,

dredger
14:26:20 Thu
Jan 5 2012
Re: Dredging w/Hydraulic Excavator
Blue circles indicate roller wheels, which allow the trommel to spin, no covers or superstructure are shown in the diagram, also please excuse the orga diagram, it does not look much like an orga used as a post hole borer,

So the line of thought is a normal type trammel, thick wire screen or perforated /or rolled punched plate screen, standard as used in the past and present, "trommels" , say perhaps 6'dia,20' long, , from memory the gravels travel around/rolls around inside the screen until it finds a empty hole in the thick wire mesh, or punch plate, and the undersize gravel falls through, or a slightly bigger rock gets jammed, following gravels either pond it through the hole, or jamb it solid, ??,for some time, I would suggest any size trommel has it production rate, or trommel size equals amount of materials effectively screened per hour, this is a well proven method for classification, size equals cu/yd per hour,

As well as other methods, there are shaker screens, again size equals cu/yds per hour, ( slightly less blockages in the screen,). I think,

Please note , at this point, I would suggest a" bar orga" type trommel would not be suitable for working in slate type ground, where a sliver of slate might be 1/8" thick x 4" long x 4" wide, only suitable for river shaped gravels,

Got to be quick, so the line of thought is a " bar/orga type trammel concept, will be capable of a size equals cub/yds per hour, formula similar to above, but I am hoping that by increasing the speed, or rpm, the orga will increase the amount or cub/yds per hour, so, the undersize gravels do not fall or find a empty space to pass through the screen , they are actually forced into the screen gap, and forced through the screen by following gravels, the idea being, increase the rpm, increases the force/rpm, in turn increases/ the volume of gravels passing or being forced through the screen, ????? guess guess,

please note this concept is more intended for classification of gravels pre-classified gravels say 1" down to 5/8", another trommel bar screen for 5/8" down to 1/2", and smaller and smaller , say about 5 trommels in all,

One scenario " could be " that as the trommel revolves, the undersize gravels are forced through the gaps, at the point of contact with the orga edge/lip, and cause gravels to be or allot of gravels to be forced through the screen and shot out, some/allot smashed into undersize "size ",

In the same scenario the or each trommel would have to be fitted with a manifold or hopper under the full length, to catch and funnel the undersize to the next trommel, and a cover over the revolving trommel to stop water spray and high velocity undersize gravels forced through the screen with enough force rpm to cause gravels to be projectiles, make a heck of of alot of noise as the gravels, or volumes of gravels hit or strike the under belly hopper, and upper full length cover,

Please visualize a length of pipe 15' long, by say 18' dia, on an angle say 5 -25 degrees, guess guess, and a good fitting orga spinning at a rpm to cause gravels to be drawn up the pipe at a velocity, that causes a fountain of oversize gravels to pour out, the high end of angled pipe, now visualize the pipe is the bar screen,

Ok, so if, if, if ,that worked, I would guess all 5 bar trommels / orga would or could be classifying perhaps 10 times more 1" then two 32 ton excavators could supply, so the rpm of the bar trommel, and the orga could / should reduced 10 times, to perhaps 1/8 cubic yards per sec, of pre-classified, Sg concentrated, super cons, 1/8 of a cubic yard of cons divided or classified between 5 = 15' long x 18" dia bar trommels per second, ???>

Note to self, next is possible scenarios for wear factors, how often all 5 screens will need to be replaced, ect, ect, guess, guess, ???

:confused: :smile:


dredger
04:11:34 Sun
Feb 17 2013
Re: Dredging w/Hydraulic Excavator
http://bb.bbboy.net/alaskagoldforum-viewthread?forum=2&thread=1651

back asap,

Fleng
19:02:10 Mon
Feb 18 2013
Re: Dredging w/Hydraulic Excavator
Fascinating thoughts dredger. Thanks for the bump. Just spent the last hour reading the thread-couldn't stop!
Getting lots of good ideas from your experienced thoughts.

After seeing Tony Beets' oscillating sluice I must say that replacing expanded metal or hardware cloth is a necessary cost of operation. The ability to process large rocks must be weighed against their ability to destroy the processing machinery. i'm almost thinking that 1' boulders need to be classified, washed, and processed in a separate channel from the ordinary pay gravel.



geowizard
15:54:07 Tue
Feb 19 2013
Re: Dredging w/Hydraulic Excavator
Fleng,

That's an important point!

I agree, dredger has provided excellent information!

In my Maxi-Banker, I incorporate a grizzley into the screen. The screen is supported with cross pieces spaced about 11 inches apart. The screen is angled away from the plant and the loader. The cross pieces are 1" Unistrut (aka Telespar).

- Geowizard

dredger
06:24:40 Wed
Feb 20 2013
Re: Dredging w/Hydraulic Excavator
Sorry guys, I am working on it, :confused:

dredger
10:10:50 Wed
Feb 20 2013
Re: Dredging w/Hydraulic Excavator

Hey guys, sorry,I have been so dominated with other stuff for so long, :confused:
However, :smile:
I added the shaker table thread with another line of thought, it is still relative, but considering Fleng and Geowizards and peluks kind words of interest in a compressor concept, thanks very much guys, I think we should continue with the above compression sluice concept, and hopefully some further development in construction,
I skipped through the previous discussion on the thread pertaining to CSC, and have the line of thought that i missed my line of thought concerning point of interest using the different mats, and a little tiny bit of theoretical theorizing on gold sizes and sources. And the question, could a compressor mesh and mat sluice be more accurate at recovering ultra fine gold better then a shaker table, ??, Or, could a mesh and matting sluice be place behind a shaker table to catch whatever the table loses, ??. And how to apply this concept to a high banker, or 8 dredge,
One source of gold that I have not heard much of is the gold mined through stampers, lots of stampers, lots of gold lost, there are lots of stampers in my area that erode into my river dredging operations, , it is my opinion that in my area, there were allot of stampers , mining records show allot of gold losses, So in my situation I believe there is a great deal of gold that is an added source to a natural gold producing eroding area, creek/ river,
And good reason for me to focus on its recovery, which in turn will improve fine natural gold recovery, and another good reason that might come back to me, soon,
So for the new guys the scenario goes like this,
Hard rock miners dig out a hell of allot hard rock and gold, put it through stampers, allot of gold is lost as free floating, a hell of allot as small balls of amalgam, washed off the copper tables covered in mercury, the crushed rock and gold washed over the table, gold is supposed to amalgamate with the mercury on the table, new guys please note, as a rule mercury and gold can amalgamate and the amalgam ball contain 60% gold, so if a stampers operator was not experienced, and or gold amount of gold in the raw rock rose without notice, the mercury would load up with fine gold quickly, and form balls that were washed over and down the table, and off, looking something like this,

testing

dredger
12:30:15 Wed
Feb 20 2013
Re: Dredging w/Hydraulic Excavator
this pic shows draining the liquid Hg off the metals.

this pic shows a wet /dry amalgam remains,

This pic shows dry amalgam ball, which is gold,
sorry got prob, basap.



dredger
00:36:38 Thu
Feb 21 2013
Re: Dredging w/Hydraulic Excavator
this pic shows top right, 3 dry amalgam balls,

this pic shows dry amalgam balls break up easerly.

More dry amalgam balls,

testing.

dredger
00:45:33 Thu
Feb 21 2013
Re: Dredging w/Hydraulic Excavator
I would suggest This pic shows a ball of amalgam trapped in a layer of gravels before it dried out,

dredger
00:49:07 Thu
Feb 21 2013
Re: Dredging w/Hydraulic Excavator
More signs that an amalgam balls dry out trapped in gravels,


dredger
04:23:25 Thu
Feb 21 2013
Re: Dredging w/Hydraulic Excavator
sorry having probs with photobucket. back asap.



dredger
04:37:34 Thu
Feb 21 2013
Re: Dredging w/Hydraulic Excavator
111, So, the bad news about thinking that amalgam balls could be a payable gold source, is a dry out amalgam ball contains very small fine bits of gold, which easerly are crushed by hand with a small rock, in a grinding fashion, meaning most dry amalgam balls are ground in to fine gold in by the creek, some like the ones I find are still complete and in a ball or peanut shapes, my line of thought is a few survive but most are ground to very small gold,
Please note, some amalgam balls shown above are made up of super fine bits of gold, ( Likely to have been crushed in a stampers), and some appear to contain small water worn flakes, (As found in creeks or beaches ), as seen in the pics above,
Please note I have observed both super fine and small water worn flake balls in my area, creeks and rivers, perhaps suggesting amalgam balls end up in a river in two ways, 1, from stampers,2, when Hg is used “ in” a sluicing operation often associated with hydraulic mining, , New guys please note, history confirms Hg was placed in troughs in large long sluice boxes. Around a ton of Hg in a big sluice was common,
So, the line of thought is crushed fine gold from stampers, and how small is the fine gold when the ball is crushed and ground by erosion, moving down creeks and rivers, ??,
This pic was very hard to take and there are 2 small black rocks, and a few tiny black bites, but the rest is tiny gold bits,


dredger
04:43:09 Thu
Feb 21 2013
Re: Dredging w/Hydraulic Excavator
Next pic, is refocused on the hair, shows tiny gold bits on the 90-100micron hair, some bits perhaps around 30micron, gold laying on or attached to the hair, are there, due to electrostatic effects,



dredger
01:31:57 Fri
Feb 22 2013
Re: Dredging w/Hydraulic Excavator
pic 1.


dredger
01:49:50 Fri
Feb 22 2013
Re: Dredging w/Hydraulic Excavator
pic 2.

pic 3.


dredger
10:11:51 Sat
Feb 23 2013
Re: Dredging w/Hydraulic Excavator
Ok, new guys please note,
Randy Clarkson, said and showed riffles /vortexes ( gold sorting crescents ) hard pack or hard pan in 12 minutes of starting up and running a sluice,, and flat flaky gold and or chunky round gold can simply ride over the hard packed gravels, and out the back, and I agree,
a couple of scenarios,
Fitting a compressor concept to any sluice, high banker , can be fitted with suction, or dredge sluice, I would suggest would be a big advantage, perhaps a very quick de- compression, fairly slow re-compression, perhaps once every 10 minutes, ????. Hope fully eliminating hard packing,
Line of thought here is the mating should begin sluicing compressed, and the decompression stroke be say ½”, depending on the number of layers of mating, maybe up to 1” or 1 and 1/2 “ , with the line of thought that as sluicing continues, the compression stroke is decreased, and the gold storage capacity is increased,

ok I think some sketches might be easier,
Back asap.


Coeur_D_Alene
20:45:19 Sat
Feb 23 2013
Re: Dredging w/Hydraulic Excavator
Kind of Off your main thought process but...What about some kind of a water hammer effect that will "drive/push" the fine gold and heavy's through a "P" trap type vent in the form of a sandy heavy slurry into another vessel/cons trap. Sorry probably thinking to technical.

dredger
22:32:46 Sat
Feb 23 2013
Re: Dredging w/Hydraulic Excavator
Hey Coeur_D_Alene

Bit tec for me, any chance of you doing a drawing please. :confused:

dredger
05:05:07 Mon
Feb 25 2013
Re: Dredging w/Hydraulic Excavator
The variation of number of layers of matting, and drawing the matting, variations in mesh, and drawing the mesh, perforated metal, and drawing the perforated metal, variations of water flow direction, and drawing the number of different water flow options, ??? and variations that could be tested to fine tune the concept is extensive, so I am thinking of some pictures, might be better, ???.
But first I should finish what I was saying, above,
Line of thought here is the mating should begin sluicing compressed, and the decompression stroke be say ½”, depending on the number of layers of mating, maybe up to 1” or 1 and 1/2 “ thick , with the line of thought that as sluicing continues, the compression stroke is decreased, and the gold storage capacity is increased,
Please refer to pics on previous pages, 3, and 4,
One Scenario, a good size high banker with 3” suction set up, fitted with the compressor arms, sponge attached to thin fine matting is laid in the bottom of the sluice box, on top of that can or could be a large hole ½”perforated sheet, on top of that is a layer of fine expanded mesh, the mesh open is facing back up the flow, on top of that is 2-3-5 layers of matting, on top of that expanded mesh suitable to is size screen usually fitted to this high banker, the compressor arms are fully compressed, sponge is fully compressed, layers of matting are also compressed,
Just one of many variations of “ operating methods for fine tuning “could be, the sluice is run for 10mins to move some top over burden, wait until the flow is clear, then the operator then releases the compression lever, slowly, the flow remains clear as some of the lighter coloured gravels moving in the vortexes are pulled down into the matting by the “ water /flow “ being sucked or displaced down through the matting, into the expanding sponge, the operator then squeezes the handle so as to compress 1/3 of the sponge thickness, causing the sponge to force water to displace upwards, and fluidize materials in the mating and lift silt and lighter material silt up into the flow and visually seen, repeating this 1/3 compression of the sponge should clear most all silt from the sluice, then the operator might vigorously compress the sponge 2/3 of sponge, and see light coloured sands being lifted and reintroduced to the flow, and move down the sluice, in turn vigorous pumping which compresses the sponge and matting should eject brown and dark colour heavier gravels back into the flow to a certain extent, he re-sets the compression lever to compress the sponge and the mating,
So the operator gets a feel for it,
And get to sucking or shovelling , for 15 minutes, then just let the flow run clean so the operator could see lighter gravel moving in most vortexes caused by each and many riffle like expanded raised sections of the expanded mesh,
((( ( right angle riffle also show materials moving around in the vortex action, )( new guys please note these rantings), = A vortex powers the live crescents and scourers the mat, and in my opinion is the optimum point where gold is recovered, the vortex must have enough energy ( spin) to scour the matting and keeping medium Sg gravels ( med dark to light colour) moving in the live crescent. However, once allot of black sands have been run through the sluice, b/s and heavies quickly build up under and around the live crescent and restrict it, and visually making the live crescent area smaller, these materials pack hard, and gold is rejected to the next vortex, so my suggestion is to keep checking the size and energy of all vortexes, ))) ( also have the thought, that when heavy Sg gavels are added to a given body of water, the body of water “ looses energy ”. )
At that point the operator could release the compression arm lock, and release the lever just enough to allow the mating to decompress and open more storage area in the “ mating”, “without compressing the sponge, or causing water pressure to be forced up though mating “, I would suggest the operator would see materials fall into the matting that were moving in the live crescent, recompressing the mating should be enough movement to cause heavy Sg gravels to sink below lighter Sg materials, re-present the lighter materials back in to the vortex, ??, after a few squeezes, but defiantly eliminating hard panning or hard packing in the vortex peripheral, freeing up the live crescent where heavy Sg materials are separated from lighter Sg materials, and forced into the matting for storage and further Sg separation,
Please note, in another scenario, perhaps testing will show that by allowing say 1/16” or 1/8” decompression of sponge in the above scenario or high banker sluice may encourage better or be more efficient Sg sorting in the matting, ??,
Rule of thumb concerning compressor concept is the sponge is only soft, and compresses easily, layers of matting are harder to compress, and only begin to compress once the sponge is completely compressed, that is how it works, works meaning there is an accurate separation by specific gravity with in the matting and below the forces of rushing water above the matting, as mentioned earlier, the compression stroke can be steady increased to increase storage area within the matting, , perhaps though out the day, or a few days, ?? Depending on the richness of the ground,

As to a high bankers or dredge ability to recover micron gold similar to shown above, I would suggest any micro fine or fine caught in my dredge was basically by chance because the water flow in my centre sluice was to high and fast, am I guessing in saying most fine gold travelled in the flow above and out of the level of flow that travels through and powers the vortexes, side box were a diamond pattern, may have caught by chance some extra fine gold, the screen was a joke and not designed for gold in suspension, and there was always some under screen size gold in the centre sluice,
Highbackers do also run high and fast levels of water flow over the riffles/ mesh, relatively speaking, so some fines must be carried away, but, if any super fines or fines or even small gold do travel in the flow that is powering the vortexes, I would suggest micro fine and fine gold would be subject to “ a better chance “ of be being forced into the matting, hit mating or other gravels and stop dead, and settle into and on mating, the chance of this happening can only be increased by having a good vortex, live crescent, and clear visible scoured section of mating, I guess.
I am still confident the sponge will not be much of a problem concerning silt build up, but you never know,
Next is some more blar blar on placing a compressor concept behind a Gemini table type shaking table,
:confused:

dredger
23:40:46 Mon
Apr 29 2013
Re: Dredging w/Hydraulic Excavator


testing.

dredger
00:26:04 Tue
Apr 30 2013
Re: Dredging w/Hydraulic Excavator
When buying a excavator all pins should be checked for wear, and asked if any pins have been replaced, bushes, or turned, in my experience there allot of people either do know pins can be turned, and allot of people do not know or care, odd or fresh shades of paint could be a clue, or similar brackets or extra holes more clues, some may say the pin has been replaced,? But it has only been turned, some people replace pins and bushes when only half worn, ?, So basically any pin could be any condition,
So if you do not know, to extend or get extra life of your pins and reduce the machine slap with worn pins, usually they need to be machined and turned, and welded again, big dollars, or you can make a bracket or drill the pin or pin collar, as follows,
1, being one type of pin lock, (and bolt) top view, this pin cannot be turn unless you machine it, turn it , then welding again,
2, being side on view ,
3, being made up bracket that fits over the original pin lock, that has been turned 180 degree,
4 is top view of made up bracket,
5, is another type of pin lock,
6, is the pin,
7, is extra hole drilled in the collar allowing the pin to be turned Ό at a time,
Back asap,


dredger
09:19:40 Tue
Apr 30 2013
Re: Dredging w/Hydraulic Excavator
Ok, sorry, got to change direction again but still on thread “dredging with a excavator”, focus is re-focused on a sucker nozzle due to a few interesting new ideas,
This concept of “dredging with a excavator “ requires,? a excavator, large vol, thin v-bucket, 1m wide with 2cum capacity, a sucker nozzle which is fitted with latest modifications, and a large sluice, that all, just a sluice, or large volume processing unit,
My line of thought is the latest mods ideas to the nozzle will increase production heaps, 2 maybe 3 maybe 5 times that of a normal dredge capacity,
Please note, also, the line of thought is to move the dredge “pump” into the nozzle, and power the dredge pump (1500gpm Keene) into the sucker nozzle, along with a high pressure blaster pump ( 350gpm Keene ), hydraulic drive off and with the power of the excavator,

Point of interest, both pumps will be self priming, no troublesome foot valves, and controlled by the operator,
As much as I would like to think through this with you guys, I should be a little busy over the next few days, so as per usual next posts will be erratic,
Back asap.


klondike_jake
06:18:51 Wed
May 1 2013
Re: Dredging w/Hydraulic Excavator
why not do 90 % of the work with the excavator then flood the hole and use the dredge to just clean the bedrock good.


kaveman
15:10:36 Wed
May 1 2013
Re: Dredging w/Hydraulic Excavator
Quote: klondike_jake at 06:18:51 Wed May 1 2013

why not do 90 % of the work with the excavator then flood the hole and use the dredge to just clean the bedrock good.


That's exactly what we're doing. Been trying to do it for the last three years, but have gone at it from every conceivable angle and haven't succeeded yet. Tried dredging in 5-7' of zero visibility water/mud and failed. Tried several different iterations of the sucker nozzle(and failed). Now we're about a week away from trying to clean it up with a dredge in 1-2' of zero visibility water. I can see many problems with that in the near future, but will report what we find.

Mechanized would sure be easier, but I just couldn't seem to get anything through the nozzle from the excavator. I may have pictures,.....maybe even vids,.....but I lost everything from 2012 in a hard-drive crash and haven't sorted out what I've been able to recover.

dredger
04:09:44 Fri
May 3 2013
Re: Dredging w/Hydraulic Excavator
back asap :smile:

Fleng
17:38:22 Fri
May 3 2013
Re: Dredging w/Hydraulic Excavator
Anyone tried using a submericble slurry pump? Here's a used 6" for sale for $1500.

http://www.ebay.com/itm/Submersible-slurry-pump-/181128455376?pt=LH_DefaultDomain_0&hash=item2a2c18e4d0


ebay item [208 clicks]


dredger
03:20:48 Mon
May 6 2013
Re: Dredging w/Hydraulic Excavator
Sorry guys , been on the road 5 days, and busy as right now,
Hey jake,
I agree very much, but for the new guys information, we also have to consider which %90 we are talking about,
For example, placer situation, and the top layer is glacial silt, ect, with no gold bearing gravels, laying on layers of gold bearing gravels,
"Why not do 90 % of the work with the excavator
Then flood the hole and use the dredge to just clean the bedrock good ",
Agreed,
Another example is in my situation where river gold bearing gravels start at the top, so I dig a hole which is full of water and I wash everything, as part of the method of dropping in the gold as I dig the hole,
So new guys please note we are talking about removing gold bearing gravels and none gold bearing materials, and either having water in the hole or not, ??. so,

My line of thought right now is about getting fresh clean water in the work hole, filtering dirty water and even recycling filtered dirty water into the work hole,
More dredging with excavator stuff, please note the first sketches, tapping into the flow, and recycling filtered clear water back into the work hole,
http://bb.bbboy.net/alaskagoldforum-viewthread?forum=2&thread=506&postnum=0
New guys Please note in the aerial pictures (two sites, USA and Australia) the flowing stream there are small rapids, this indicates the water flow is falling at a good angle, that and the fact if you dig a hole out of stream in the gravels it will fill with some or allot of water, my point being you can tap into clean filtered water moving through the gravel bed, ok it is dirty when it is dug, but quickly clears,
Trench.

I cut this trench as quick as I could just to get clean water from the flow on the other side of the river, I also observed that soon more water was filtering with the high side wall of the trench then was coming from the river flow, which was enough to have clear dredging water, please note digging the hole and trenching results in dirty water for a short term, then the mud settles, 3-6” deep, so if you are a new guy and never actually dredged before, you will quickly learn to keep the water clear, you suck up the mud layer before disturbing it, it is that easy ,

Filtering dredge tailings water is in my experience is a little tricky, for the new guy with no experience, some good tips coming asap,

dredger
07:23:38 Sat
May 11 2013
Re: Dredging w/Hydraulic Excavator
I said,
Hey jake,
I agree very much, but for the new guys information, we also have to consider which %90 we are talking about,
For example, placer situation, and the top layer is glacial silt, ect, with no gold bearing gravels, laying on layers of gold bearing gravels,
"Why not do 90 % of the work with the excavator
Then flood the hole and use the dredge to just clean the bedrock good ",
Agreed,
Now the bit I forgot,
I should have been more specific and said " use the sucker nozzle attached to the excavator to clean and recover most gold on bedrock or on hard packed layers,, then the diver goes in and quickly checks the bottom, and does any crevices”,
Another new 30 sec old thought is to fit a clip on suction hose for the diver?? 5”, to the suction nozzle, ??. so the excavator fits the sucker nozzle, and starts sucking the bottom, after Ό of the hole /bottom has been sucked clean, the water in the hole will be clear, the diver takes his ?? 30’ of?? 4” very flexible suction hose, and attaches his hose to the excavator suction nozzle , and both the diver and the excavator operator can work / suck safely because the water is clear, and the excavator operator can see everything, and focuses on moving the machine slowly around the other end or Ύ of the hole, more on the new ideas on a super excavator suction nozzle coming,
Back asap


dredger
02:34:16 Tue
May 14 2013
Re: Dredging w/Hydraulic Excavator
Ok, am having trouble with photobucket, so I will have to leave the filtering tips until I get photobucket working,
One point of interest that sticks in my mind is about digging a hole in dry ground then filling it with water and dredging it,
Generally speaking to new guys, I suggest this line of thought be maintained, the dredge hole or more important the height of the water in the dredge hole is a important factor, as opposed to digging the tailings filter dam,
In fact, when the hole remains open over night, next morning the dredge hole will be full, and the tailings dam will be empty, drained over night,
So I would suggest to keep the work hole more like a swimming pool, as opposed to the tailings dam aka drainage pit,
My experience is to tap into the main flow, my observation was while digging the intended hole, it fills with water, the focus was on dropping the gold, by washing the gravels using the forces the excavator does produce, which forces most clay silt mud into suspension, and because the water level is as high as I can get it, that water is actually being forced through and out the surrounding gravels walls, carrying the silt with it, resulting the walls block up with silt, at which time you have to start restricting the flow into the hole,


Cooks on site



dredger
00:40:30 Fri
May 17 2013
Re: Dredging w/Hydraulic Excavator

testing

dredger
23:44:42 Fri
May 17 2013
Re: Dredging w/Hydraulic Excavator
Please note the height of the water in the work hole in both above pics, new guys please note the method being used, is focused on the sluice being placed or laid on an undisturbed gravels dam wall, the 12’ long x 6’ wide triple sluice basically has no frame, or floats, to get the sluice as low as possible, the focus is on raising the water “ under “ the jet to minimize lift in the expansion chamber, / jet, and level with the bottom of the box “at the head “, this improves dredge performance,
Please note top pic shows water level in the tailings dam is a few inches above the rear of the sluice, ( it takes a few hours of dredging to bring up the tailings dam water level, at which time I lift the engine pump frame up a few inches setting the level so the foot valves are only have a few inches lift,
Dig time was about 2 and ½ hours, rehab about 2 hours,
back, asap.

dredger
04:56:48 Mon
May 20 2013
Re: Dredging w/Hydraulic Excavator
Please note the height of the water in the work hole in both above pics, new guys please note the method being used, is focused on the sluice being placed or laid on an undisturbed gravels dam wall, the 12’ long x 6’ wide triple sluice basically has no frame, or floats, to get the sluice as low as possible, the focus is on raising the water “ under “ the jet to minimize lift in the expansion chamber, / jet, and level with the bottom of the box “at the head “, this improves dredge performance,
Please note top pic shows water level in the tailings dam is a few inches above the rear of the sluice, ( it takes a few hours of dredging to bring up the tailings dam water level, at which time I lift the engine pump frame up a few inches setting the level so the foot valves are only have a few inches lift,
Please note last pic, the dredge pumps are positioned in the tailings dam, also please note in the above larger picture, the rear of the sluice cannot be seen, but the 13hp red engine cover can be seen mounted in the frame, (petrol tank is removed) black exhaust cover can also be seen, please note motor sits in a s/s metal tray,
Please note the water level in the tailings hole will rise quickly, once the water level rises above the frame base, and the s/s metal tray more or less floats, this results in the pump inlet will only be a few inches above tailings dam water level, (less pump lift ) water level in the tailings dam is easy and quick to control,
Why control,??, = Minimum environmental foot print, and how long a tailings filtration dam has to be , and constructing a suitable efficient filtering dam to suit an 8 dredge water through put,
In my situation in my area, river erosion, rocks and all look roughly the same, as most other rivers, I would suggest a 8” dredge operation would require a 40’ tailings dam including foot valve area and 20-30’ filtration wall,
And I am guessing that a 10’dredge operation in the same river hole / materials might have to 60’ long respectively.
The length of the tailings and filter dam walls is relevant to the water through put of the dredge nozzle,
Back asap,


dredger
05:49:14 Mon
May 27 2013
Re: Dredging w/Hydraulic Excavator

Please note, the filtering dam walls stop filtering as the silt builds up on the inside of the filtering dam wall, my experience was to dig the hole shown in pics, then a few days of dredging and crevices. I would see the tailings dam water level rise up to the catch tray, ?? (New guys please note the catch trays under the motors are to catch any or all oils that maybe accidently escape from the pump motors, and is part of the EPA Lic requirement,) At which time I use the excavator to skim the built up silt, building up the filter dam wall, this can be done very quickly, just by setting the bucket to skim the built up silt off the wall, and walking or driving the machine forward 30’ parallel to the dam wall,, and back again, a few minutes operating the excavator clears the silt for a few days more dredging, or just by using a wide broom, to sweep the built up silt, down off the wall into the trench, 10 mins,
So, at that time, my observation, was I quite surprised to see amazingly clean clear water about 4” deep flowing freely along about 30 feet of dam wall, into the main flow, “ in the beginning “ or when I first started dredging with a excavator, I dug long 100’ tailings dams, which works great, with hardly any filtered water passing through the wall into the flow, in fact, the dam wall was placed between the tailings dam the main river flow to stop the turbid tailings water entering the main river flow at all, which evolved into the “ small environmental Key hole mining foot print, focus of keeping the foot print or total surface area to a minimum, this also reduces the or any “bond” or moneys paid for or to ensure rehab.
New guys please note, I observed enough to suggest the best dam gravels to filter silt is not the light Sg gravels found high on the river banks, only the gravels found or travel in the main flood run carry the heavies, ( black sand and Gold ), do provide quick working and efficient filter medium,
Back asap.

testing.:smile:

dredger
02:55:40 Fri
May 31 2013
Re: Dredging w/Hydraulic Excavator
Please note, I had already started back filling or levelling the rear of the rear of the tailings dam before I remember to take a picture, confused: sorry.
New guys please note, the large tree near the hole/trench, also in the river gravels as reference,
Please note the water height of the river,
On left of pic shows shallow tailings trench, with 3-4 foot wide base x 3-4 foot high filtration wall, on right side of trench.
Please note there is really no wall on the left side of the trench required, the rear of the trench I usually just curl the tail of the filtration dam,
Please note that the filtration dam and walls are basically very quick to dig, extend, modifying,
Sorry, back asap.


dredger
03:53:59 Sat
Jun 1 2013
Re: Dredging w/Hydraulic Excavator
I have been having trouble with photobucket, my fault more then theirs,
Work site clearly marked ,

Worksite fg,

Work site after rehab,

testing, :confused:

dredger
00:48:42 Mon
Jun 3 2013
Re: Dredging w/Hydraulic Excavator
Ok that worked, :smile:

I have been trying to get "to " these pics to post them for weeks, my fault,

New guys please note, if you click on reply, you can scroll down and see all the work site pics on one page,

I refer back to the pic showing the rear of the trench, ( and drunk sleeping it off ) my line of thought when digging the trench, is first I dig a deep hole behind the sluice, for the tailings to build up in, ( and i dig out those tailings a few times a day, takes a few mins each time, ),
Then continue 10 – 15 feet of straight trench to direct the flow from the rear of the sluice, then I cut a trench back, Y section, 15' trench back to the foot valves, make a PAD for the engine frame, then back to the main trench, where I leave a “ dam” in the trench, please note this first sections of the trenchs have to be deep enough to ensure there is water covering the foot valves in the morning, the dam restricts the flow out of the front section or Y section trench, the focus is as soon as the pumps start pumping, the jet starts moving allot more water down the sluice, around the Y section and feeds the foot valves asap, the water level rises above the trench dam and flows down the remaining length of the trench, to the filtration wall section,
sorry back asap, dredger.




Dredging w/Hydraulic Excavator
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