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6 mm rule

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6 mm rule

Postby mksanders2020 » Sun Dec 24, 2017 6:05 pm

My goal is to make the walls of my large bowls as thin as I can. I'm using two layers of thin Cloud Opal. I slump into a shallow mold and then the deeper (custom) mold, using Steps 1 and 2 of the 3-step slumping schedules. Due to the 6mm rule, the glass recedes...about an inch from the top of the mold. If I use a slower rate will the glass recede less?
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Re: 6 mm rule

Postby marykaynitchie » Thu Dec 28, 2017 10:05 am

My guess is that with a deep mold, the glass will recede even if you fire it at a slower rate, or lower process temperature. However, it is impossible to do more than guess unless we know the mold style number, the cycle you used, and the size and dimensions of your glass blank.

Feel free to post again if you want to share those details!

Mary Kay
Mary Kay Nitchie
Bullseye Glass Co.

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