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Post by docone31 on Nov 19, 2003 21:03:05 GMT -5
Stones do not take that much heat to melt. 2300 degrees is quite sufficient. It is a question of atmospheric contamination. I melt silver in the microwave, I also make a kiln out of a clay flower pot lined with aluminum foil over a coleman camp stove. Single burner. That is what is so fascinating about this whole thing. There is flux induction for gem creation, there is pulling, there is reducing flame, enrichening flame. I melt metals, and refine precious metals. Mostly I use borax, heat, a graphite crucible. With small diamonds, when I melt gold for scrap, I melt the gold and keep heating. The diamonds will also melt and disappear. With metals, the more you heat and melt the button, the more brittle the metal gets. I would have to presume, the same applies to gem material. A melt would have to be done once, and correctly. 92.5% silver, 7.5% copper and you have sterling. The alloy once remelted gives up a percentage of copper. Making Hallmark silver. The key would be the melt temperature, time, and atmosphere. Gold is the same, 14Kt is 52% gold. Remelt it, and the karatage goes up, and the brittleness also increases. High heat turns it red. Black hills gold is just over heated karat gold. I presume the same applies to gems and manmade gems. Controlling the factors produces consistancy. Brown ziosite heated becomes tanzanite. Amythyst heated becomes amatrine.
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Post by hermatite on Nov 20, 2003 10:46:38 GMT -5
Okay, now I'm really intrigued. A clay pot and a coleman stove and you have a kiln? I've just tried my hand at enameling and would love to do more, save the fact that I am NOT about to invest in a kiln. But building one that sounds as simple as that...now there's an idea with merit. Are there plans somewhere on the net for such a thing? I'd love just to give it a whirl.
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Noah
starting to spend too much on rocks
Member since November 2003
Posts: 102
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Post by Noah on Nov 20, 2003 13:36:09 GMT -5
Actually believe it or not...i made a kiln out of a 3 yr old weber BBQ ...I closed up all the grease drainage pans...closed up the lighting holes...took out all the unneccessary parts...and then changed the burners to have larger burst holes...then I had a friend fill me a propane tank with 1/3 Methane 2/3 Proprane....Methane burns at a higher rate so it creates a hotter flame maxng at 1356 degrees...This is enough to do plain pottery kilning...but...i think if I wanted to i could do an add on shaft that would drop a chemical in like borax in...that would get the flame close enough to the proper temperature for gemming..then you have your environment, and just cut in two holes and install a set of what I love to call uber gloves...basically similar in design to the type of equipment they where in space...it resist 3000 degrees temperature
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Post by docone31 on Nov 20, 2003 22:19:01 GMT -5
You are on the right track with the Weber grill. Now, gas flame temperatures. Propane is 4300 degrees at "clean" burn. Acetelyne is 6300 degrees. The difference with the grill, and kilns is btu's, and displacement. There is a wonderful tutorial on the net, on making an aluminum furnace. They use a water heater, and one uses the grill. Using refractory firebrick and making small increases the available btu's. Acetelyne produces carbon even with O2. Propane, and methane is really clean. When I use a flower pot, and a coleman stove, I can get a clean 1500 degrees with a pyrometer. I made a small kiln out of six firebricks, nichrome wire, and a light dimmer, 1000 watts. I get a steady 2300 degrees. I have also stacked two propane torches, upside down, and got 2300 degrees. If you made the grill volume smaller, or increased the flow you would get an amazing temperature difference. The tutorials on melting aluminum give details on increasing the flow, and volume requirements. Very well designed. Very inexpensive. Sterling de-alloys at 1800 degrees. With flux of course. I have melted diamonds with a Bernzomatic torch. I had to use a reflecting medium, a shielded crucible, and they were just 1/2 point chips, but melt they did. It is all about volume, time, and flame.
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Noah
starting to spend too much on rocks
Member since November 2003
Posts: 102
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Post by Noah on Nov 21, 2003 2:24:33 GMT -5
Yeah the methane definately burns cleaner...I totally forgot about acetelyne...hmm... Well the BBQ works nice for when I play with clay...but going above 1536 might not let me use it as a kiln for clay anymore...unless I really had fun and made it have like variable temperatures...but I haven't messed with electronics in a while....
Off topic for a second, but does anyone have a site that sells unprocessed copper...i'm looking to experiment with some acids and copper. But processed copper has stuff added to it.
Thanks, Noah
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