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Cracks when slumping

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Cracks when slumping

Postby tallteacher64 » Fri Mar 23, 2018 11:38 am

Hi! I am a newbie and could use some help. I made a 10" bowl with a sunflower by adding pre-fired petals, 1/4 " dots, and frit to one layer of Tekta clear. Everything went great making the blank, but after slumping I have several cracks running through parts of the bottom layer of Tekta. Here is the schedule I used:

300° 1000° 10
300 ° 1260° 10
9999 950° 45
125° 700° 0

What caused the cracks? How can I avoid this in the future?
Can I repair the cracks by heating it to a tack fuse in the mold?
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Re: Cracks when slumping

Postby jestersbaubles » Fri Mar 23, 2018 7:54 pm

I see you got answers on a FB forum, but to recap... In your schedule you are ramping too fast and not annealing long enough. A good rule of thumb for a safe, conservative annealing time is to take the recommended time for the largest number of layers and then double that.

Dana W.
Dana Worley Fused Glass Designs
dba Jester's Baubles
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Location: Logan, UT

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