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Old 03-30-2005, 08:55 AM
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Pete VanderLaan Pete VanderLaan is offline
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Originally posted by Robert Mickelsen
glass. For instance, there is an opal green that is notorious for crackling when incased. But the measured LEC is dead-on that of clear boro glass. Why doesn't it fit?
Fascinating discussion folks. Please continue...
When you say it is dead on, who measured it and how. Is it a pull test? I simply do not trust pull tests in opal/clear matches as even remotely reliable. They only work in formulas of similar composition. It would require dilatometry or a ring or trident seal test to get accuracy here. Chrome glasses are refractory in nature and the problem is compounded by opacity. If it is a boro supplier, I have so far not been overwhelmed by the current group of suppliers being terribly thorough. It's a comparatively young industry when it comes to color and actual batching of colors.
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