Thread: Color bubbles
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Old 11-01-2017, 12:39 PM
Ted Trower's Avatar
Ted Trower Ted Trower is offline
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I suspect that rapid cooling creates bubbles in color bars the same way they form in a Prince Rupert drop. The exterior solidifies before the core goes thru it's thermal shrinkage and somethings gotta give.

Also I work out of a public facility so the color box is always hot when I get there. I have found I get fewer cracks in my color If I set a cold piece of kiln shelf under it when boxing for warm up.
"It appears to me that glass men are the most given to drunkeness of any class of men I know" Peter Burt, recruiter in Europe, in a letter to Deming Jarves of the Boston and Sandwich glass company. -1826
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