Keeping glass in contact with mold crystal clear

[deandv]

Hi all, dean here, product designer/maker totally new to glass forming.

I'm slump forming 3/16" float glass over a graphite mold, and I'd like the result to be as clear as the original glass. The glass comes out of the oven though with a hazy, somewhat rough, surface where it was supported by, or even near, the mold.

• the mold is graphite, new, pretty darned smooth
• no kiln wash or paper
• 300°/hr to 1400°F, hold 40 minutes; AFAP to 900°F, hold 60 minutes; 100°/hr to 700°F; oven off.

Is it even possible to have a perfectly clear final surface where the glass contacts the mold? Any tips on how I can get closer to that ideal?

thanks!
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