Need Input on Casting My Own Dive Weights
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waveaction
16:19:28 Fri
Apr 11 2014
Need Input on Casting My Own Dive Weights
I had purchased a Trident Lead Weight Mold and I could use some pointers, but first this is what happened. I poured the melted lead into the mold, at about 3 minutes, turned the mold over and struck the bottom a few times with a hammer and the lead weight fell out. Great looking weights the first 2 that I made. Then the 3rd time the weight would not release and I cracked the bottom of the mold after striking it a few more times. Now I should have been smart and put the mold in the pan I used for melting the lead and remelted the lead in the mold. Anyway, I have a new Trident Lead Weight Mold coming in the mail and I don't want to make the same mistake. Any ideas from those that make there own weights. I read on the internet where folks use a candle to smoke the mold to use the smoke as a release agent. Sounds good to me.

JOE_S_INDY
21:06:18 Fri
Apr 11 2014
Re: Need Input on Casting My Own Dive Weights
Hey Wavie!

The lead weight releases because, in cooling, it shrinks more inside the mold than the mold shrinks. If you try to hurry the releasing process, before the temperature of the mold >>and<< the lead aren't both cool, the not-completely-cool/shrunk weight will stick in the mold.

Another 'thing' is the composition of the mold. Aluminum or Iron. Aluminum expands / contracts ~about~ twice that of Iron. (Al = 69, Fe=33, Pb=87)

http://en.wikipedia.org/wiki/Coefficient_of_thermal_expansion#Coefficient_of_thermal_expansion --- LOOK AT THE CHART

So, bottom line is to pour a weight and then go find a glass of Pepsi and check the forum. If the entire conflagration is cool enough to pick up without gloves it should be ready to pop out.

Two things, though - NO steel hammers - something softer like a wooden mallet.

Other thing - NO water to cool things - steam explosions make you blind and burned!!! :duuuh::eeekyellow::duuuh:

As to wax 'smoke' it ranks right there with Voodoo, Zodiac Signs and other pseudo-science things.

Joe

waveaction
22:10:50 Fri
Apr 11 2014
Re: Need Input on Casting My Own Dive Weights
Thank you Joe for your input. The mold is Aluminum and heavy duty. The first pour was into the mold without heating it. The 2nd pour was after the mold was empty and was warm to the touch after about 20 minutes, then I thought maybe it is best if the mold is hot so I poured the 3rd one in about 15 minutes and the mold was still hot.

Down at the camp I work in on the South Fork near Chicken there is a lot of old weights that need to be re-poured and I had a bunch of lead here at my place (Wisconsin) so it is a whole lot cheaper to make our own in this case. Thanks Joe.

Bonaro
06:45:39 Sun
Apr 13 2014
Re: Need Input on Casting My Own Dive Weights
I dont think there is a way to offer advice better than Joe did...spot on.

The mold should be hot but aluminum transfers heat so fast that it warms almost instantly. Having a hot mold actually helps the lead flow into all the nooks and crannies before it sets. Just set the bottom of the mold in the surface of the molten lead for a few minutes to preheat.

If you cant smoke the mold with a candle you can use a bit of cooking spray or some dry graphite lock lube.

I usually use two molds. After I pour one I start setting up the second. By the time I pour the second the first has cooled and I just turn it over an the weight falls out. Tap with wood block and bang it gently on the ground if you need to.

You should flux the lead before you pour. Most lead is not pure and contains antimony, tin and other stuff which will separate and float off.. you dont want it. Drop in a small marble sized chunk of beeswax and stir before you skim the dross.

No water anywhere near where you are working...ever

waveaction
11:18:54 Sun
Apr 13 2014
Re: Need Input on Casting My Own Dive Weights
Thank you Bonaro. Yesterday I went to the local dive shop. The owner was in and he said years ago he made some of his own weights and used silicone spray to help as a release agent. Also I found on the internet a mention of dry graphite spray which you mention as well. This forum is always so useful. Thank you Jim for providing the site.

Bonaro, do you use a respirator (half mask) or just let the wind or a fan move the air away from you when melting. I see 3m makes a filter # 2297 for such a purpose. The other day when I made a couple of weights I made sure I was outside and there was a mild wind blowing at my back. The owner at the dive shop just used the wind/fan method outside.

Bonaro
17:43:01 Sun
Apr 13 2014
Re: Need Input on Casting My Own Dive Weights
Silicone spray works but I did not mention it because when it burns off it freakin reeks and the stench doesn't ever seem to come off the weights...on the other hand, you cant smell them if you are underwater.

I just keep the wind on my back or side or use a fan. I rake the dross with a piece of oak which will create fumes/smoke I can actually smell. If I smell smoke I are standing in the wrong spot.

Respirators are a good idea

Do as I say and not as I do. :thinking:

907miner
06:49:52 Tue
Apr 15 2014
Re: Need Input on Casting My Own Dive Weights

I made about 220 pounds of 10 to 15 pounders
I normally just do out side with sun glasses on but
This day a buddy wanted me to make him some so
for some reason I grabbed my welding gloves and
Leathers and full face mask which I have never use
To pour lead . On this day I had about 40 to 50 pounds
Going nice in my large kettle. But I learned a big lesson this day I used
All my lead up and my buddy had brought his lead, they were 4 and 5 pound
Halibut weight got to about the 5th one and it must have had a drop
Of moisture in side the eye let . Because it was like a bomb went off.

It splattered hot lead everywhere, most was on my full face mask, once lead hits your skin it keeps burning into the skin. If I wouldn't have had a full face and hat on that day I wouldn't be here telling you of my mistake .
make sure you put all the lead you plan on
Melting put in a dry room days before and to ask your buddy's where they
stored their led . I still pour but will always were my full face that is melted
In reminder of that day

My best tip for weights coming solid and nice is I use hot plates to keep molds warm and scape the bottom of pot to keep the lead as clean as possible.


waveaction
08:18:00 Tue
Apr 15 2014
Re: Need Input on Casting My Own Dive Weights
The one thing I have read about on the internet (other than lead being toxic) is that you do not want any moisture at all to get into the molten lead. Thank you for sharing and glad you had a full face mask.

waveaction
20:00:16 Thu
Apr 17 2014
Re: Need Input on Casting My Own Dive Weights
Here are the Dive Weights I made today. Thank you folks for the input. Soon it will be dredging time.













Need Input on Casting My Own Dive Weights
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