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Old 11-25-2003, 12:11 PM
Pete VanderLaan's Avatar
Pete VanderLaan Pete VanderLaan is offline
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Join Date: Apr 2002
Location: Chocorua New Hampshire
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the rules change in squeezing small pots. They don't squeeze well, I can tell you that. You have a dual problem of melting an antimony and nitrate free batch and melting it too cold. 2250 is too cold for a copper ruby. I melt them in the 2300's overnight, so thats like 12 hours at 2325. That fines out. I don't like using sodium fluoride because I don't like extra sodium coming from anywhere. Fluorspar is cheap and you can get it at your local pottery. 50 grams in 15 lbs is plenty. Good luck, you are going to need it. Ruby in a wire melter is an exercise in hematic livery reds anyway. They really want good old gas reduction. I don't know why the silver opals work as well as they do in electric. Silver transparants are hard. You can add the antimony to the melt but it doesn't function well without the nitrates andyou just can't add the nitrates. The bubbles you are seeing in the red are almost assuredly carbon dioxide. Hard to dump.
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