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Old 04-17-2015, 08:58 PM
Steeveedee Steeveedee is offline
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Default Melting Copper and its Alloys

Hello all,

I have a bunch of brass and copper bench shavings that I'd like to consolidate and pour for a casting. My copper and brass working to this point has been with a hammer or mill or lathe. I have cast aluminum and lead in the past, and know how to make wood, sand, and lost wax molds. I have limited experience in the copper and/or brass casting arena, though, and would like some helpful hints on the melting and pouring process and elimination of dross, etc.

Thanks,
Steve
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Old 04-18-2015, 11:52 AM
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I have lots of interest, but no advice.
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Old 04-18-2015, 04:51 PM
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I would check You-tube for a video. There are probably some there that will answer all your questions. If you have the ability to reach the proper temperatures it just procedures after that.
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Old 04-19-2015, 10:37 PM
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Quote:
Originally Posted by Steeveedee View Post
Hello all,

I have a bunch of brass and copper bench shavings that I'd like to consolidate and pour for a casting. My copper and brass working to this point has been with a hammer or mill or lathe. I have cast aluminum and lead in the past, and know how to make wood, sand, and lost wax molds. I have limited experience in the copper and/or brass casting arena, though, and would like some helpful hints on the melting and pouring process and elimination of dross, etc.

Thanks,
Steve
You will need a crucible and a makeshift furnace can be made of firebrick and a tiger torch.
The most important thing is to use a flux to lift off impurities and seal out oxygen. All metals were formed in the absence of oxygen and oxides are their normal state in nature.
A flux can be made by using Mule Team Borax in sufficient quantity to cover the melt material.
You can do without Nitrates and calcium flouride. A bit of broken beer bottle will give you enough silica...too much and the flux is gluey.

Here is my recipe for gold, it should work well on any non-ferrous metal
1, anhydrous Borax, 5 parts. [regular Borax from the supermarket will do the same]
2, #70 silica sand, 40 parts. [get it at any home depot]
3, soda ash, 10 parts.
4, sodium nitrate, 20 parts [oxidizer].
Calcium floride (Florespar) for more liquid melt
5, Now mix all of this together and store for when needed in a closed container,"keep it dry".
6, When ready to smelt your cons, add 1 to 2 parts of Flux to each part of Concentrates. Mix well and put the heat to it.
7, Put flux/cons mix into crucible and dampen with rubbing alcohol.
8, Fire up with a torch.
9, Once up to good hot temp take it up to 2000*F and hold until molten bright yellow white.
10, Prepare pour [ steel or cast iron] mold by drying it out and heating it up [few hundred degrees] and burning off a little bit of motor oil in it to carbn up the mold and make the brick come free.
Note, if the pour is to thick add some more borax to thin it out.
11, Get on all of your safety gear, face mask,long sleeve gloves, apron, also have a fire extinguisher.
12, Once ready to pour, put grabbing end of tongs into torch flame for a few seconds to heat them up, [avoid themal shock to crucible].
13, Now grab crucible and begin to pour into mold in one continuous pour.Make sure you have enough mold for "ALL" of the smelted material.
14, Once poured, set crucible on warm surface, not on cold [thermal shock].
15, Let mold cool, let crucible cool and be sure you turned off the torch.
16, When cooled gold will be in the bottom, borax glass on top, pop it out and flip it over. Tap gently and it'll come apart.
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Old 04-19-2015, 11:55 PM
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Gerry,

Parts by volume or by weight?
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Old 04-20-2015, 08:17 AM
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Gerry,

Parts by volume or by weight?
By Volume...5 cups borax, etc.
I should have thought of that.
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