Lost Password :: Posting Pictures :: Who's Online :: Stats :: Memberlist :: Top Posters :: Search
:: :: Vacuum forming/grooves
Unsubscribe From Newsletter



Welcome, Register :: Log In Welcome to our newest member, Agent67.
Users active in this forum:
Users active in this thread: Guest

2 people online in the last 1 minutes - 0 members, 0 anon and 2 guests. (Most ever was 29 at 13:36:32 Sat Aug 3 2002)

Pages: [ 1 ]

[ Notify of replies made to this post ][ Print ][ Send To Friend ] [ Watch ] [ < ] [ Add Reply ] [ > ]

Julianh
04:27:32 Sat
Jul 11 2009

Offline
8 posts
Reply
Vacuum forming/grooves

These are questions for people with experiance vacuum forming or otherwise building sluices with grooves to trap the gold instead of riffles. I Want to build a 24"x72" vacuum former for experementing with different riffle designs, but I am not sure about what to use to actualy heat the plastic. There is no way I could fit more than the corner of a sheet inside my oven, and I hear that heat guns dont work so well. I could rig an array of skillets that would heat the whole sheet, but would this be the best way? Also, I am planning on using some relatively thick plastics 1/8"+, so will I need to heat the sheet from both sides? My other question is what groove paterns sem to work best for catching fine gold. I am going to be doing LOTS of experementing if I ever get this thing going, but I just want a basic idea of what has been working so far.

  
eightymesh
12:10:42 Sat
Jul 11 2009

Offline
222 posts

Reply
Re: Vacuum forming/grooves

My neighbor set one up a few years back to make some hobby boat hulls and used an array of oven elements to hang over the sheet and a large shop vac for the vacuum part, worked pretty well actually. the hanging array of elements were a bit frankenstein but it worked

  
overtheedge
01:15:52 Tue
Jul 14 2009

Offline
600 posts
Reply
Re: Vacuum forming/grooves

Go to Lindsay Books on the web. Not sure of the web addy, but they specialize in machining and early technology books along with some off the wall subjects.

Anyway, I got my book on vacuum forming from them. It details a fair size vacuum former and uses oven elements for the heat.

Good luck, building it is on my roundtoit list.
[1 edits; Last edit by overtheedge at 01:16:33 Tue Jul 14 2009]

  
Julianh
05:36:26 Wed
Jul 15 2009

Offline
8 posts
Reply
Re: Vacuum forming/grooves

I figured out plans for the former, here is an image of my prototype sluice if anyone wants to comment on it.



  
dredger
11:13:18 Wed
Jul 15 2009

Offline
2604 posts
Reply
Re: Vacuum forming/grooves

Hey Julian,

Mate, don't worry about a slow response to your thread subject, VFG, I think most of the guys that have started vac forming are away getting gold, should be away for a few months, :confused:. which I suggest will produce alot of first hand reports on how good gold recovery is on those particular designs, I am looking forward to that,

As to comments on , here is an image of my prototype sluice if anyone wants to comment on it.

I love anything i have not seen before, 3 sections of ?? ( we can say riffles/ grooves ?? ) with slick plates and flared too, very innovative, varying energy levels in each riffle /slot due to the flare, very interesting , :smile:.

Could you please share your thoughts on what classification of gravels you have in mind, how much water might be required, are we talking hy-banker, or dredge , ect , also any and all thoughts you have , please, :devil:.

Sorry mate, gotta run, dredger,

Ps, I suggest anyone that who might be thinking of building a vac former to " tests " their recovery ideas , which would first require thinking up a idea, then building the mould , might be able to get someone that already has a vac forming set up working, to form a their working proto for them, ( from their own proto/concept mould ) I am sure there is alot of work and frustration/money to and before successful forming, ???.

Thanks for sharing Julianh, :smile:

" so will I need to heat the sheet from both sides? ", I like that idea. please share more info / ideas..


  
Julianh
04:27:01 Fri
Jul 17 2009

Offline
8 posts
Reply
Re: Vacuum forming/grooves

I just figured out what to call them! it has been on the tip of my tongue forever, but I think the proper word is "Flutes". Anyway, Flutes require MUCH less water flow than riffles because they work on a different basis. The idea behind a flute is that when the gold goes over it, it will sink to the bottom of the flute and becomes trapped. It does not require any kind of vortex or eddy in order to work. For this reason, flow on the order of 20-30 GPM should suffice, which would allow you to run this sluice box off of a bilge pump and a car battery for several hours without recharging. I would definately screen the gravel I ran through one of these, as these flutes could easily become clogged with large garnets/ hematite / bb's/ etc. You mentioned different energy levels caused by the flair, I think that the main duty of the flair will be to evenly distribute material across the sluice and allow a dampr to be used wothout completely stopping the flow. It would also provide a goot spot to put a Vortex Induced Vibration (VIV) generator because it would have the strongest current in the slucie box. As a highbanker, this would pretty much be the same thing as a G-1. I do not think that it would be viable for a dredge because a dredge has WAY to much flow for one of these. Maybe you could rig it up as an over/under sluice but I am still not sure. Anyway, I was just thinking of using this as a river sluice for now, but if/when I feel I have a very strong design, I might consider marketing them in local prospecting stores. The best part about these things is that they will cost me only about 15 dollars a piece to produce, which is even cheaper than the sheet metal I would use to produce a regular sluice. Plus, once you have the vacuum former rigged up well, it takes about 5 minutes to make one (plus some time for the plastic to cook). In any case, I think that molded plastic sluices like this are soon going to take over the market. They are easy and cheap to produce, some are very efficient, and they dont even require carpet. Also, prices of sluices should drop dramaticaly because anyone can make a vacuum former and start producing these large scale for only about 200 bucks and the time it takes to rmake a mold for an established design. .

  

Pages: [ 1 ]

[ Notify of replies made to this post ][ Print ][ Send To Friend ] [ Watch ] [ < ] [ Add Reply ] [ > ]

 Total Members: 11956

  • Can start a new thread. (Everyone)
  • Can't start a new poll. (Mods & Admins)
  • Can add a reply. (Everyone)
  • Can't edit your posts.(Everyone Registered)
  • Register :: Log In :: Administrators

    The time is now 10:17:30 Thu Dec 9 2021

    Powered By BbBoard V1.4.2
    © 2001-2007 BbBoy.net
    :: :: Vacuum forming/grooves

    [Most Recent Quotes from www.kitco.com]

    [Most Recent Quotes from www.kitco.com]