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Old 03-19-2004, 03:17 PM
Brice Turnbull Brice Turnbull is offline
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Location: Salida, CO the Happy Little Town of my Happy Little Dreams
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Richard - the 5 minutes sounds short, until you consider that it's all the way down at 1700. It takes hours to drop that far, and then about 2 1/2 hours to get back to work temp. You could probably drop to 1775 and hold for maybe 2 1/2 hours and maybe get the same result.

Actually, this is a good question - I used to squeeze at 1950 for 5 hours, but still found seeds. A couple weekends ago I was at a marble show & talked to Drew Fritts, who recommended a drop to 1500 for the squeeze, but that was in a 15 lb. crucible, and I thought it would take too much power to get back to work temp from there, so I tried my own plan at 1700, and in the two melts since then I've found no seeds down to a depth of about 6" from the surface. First time in a few months I've had glass that clean.

As far as fatigue on the elements, I recall about 4 more melt cycles without too much trouble after the recovery gets slower. I've pushed it to about 7 melt cycles also, but I think it draws a lot of electricity, and it takes a long time.
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