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Old 08-26-2020, 08:24 AM
Eben Horton Eben Horton is offline
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Originally Posted by Greg Vriethoff View Post
The answer is yes, but not because of the plaster itself, per se. As you pointed out with the binder fumes it has more to do with with the off-gassing of materials. Chemical water in plaster investment can take a long time to burn out depending on several variables. How thick is the mold? How long did it soak at temp.? If you ramp up really fast to your casting temp. there may not be enough time for the water to dissipate before your glass starts to soften. Then you're in the devit range temp.-wise, so it's a perfect storm-type scenario.
Plus the thermal mass of the mold will keep you at the de-vit temp longer no matter what.
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