Dealing with bubble in glass

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BennettS
Posts: 1
Joined: Wed Aug 06, 2025 2:52 pm

Dealing with bubble in glass

Post by BennettS »

I've been working on this bowl and got a huge bubble when trying to full fused some frit on it. I was hoping to slump it into this bowl mold.
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Is it possible to just slump it into the bowl as it is? Seeing it, it feels like the bubble has just done some of the work so far but I'm very new to glass and especially bowls, and I'm aware that that's probably not the right way to do it. I've been told that I could drill a hole in the bubble and add frit (I'm unclear where or how to add the frit and what that would do) and fuse it again to let it sink back down but I'm getting that information 3rd hand and no one in the Makerspace I'm at has done this before.

I think I figured out why I got the bubble in the first place (there was a tiny air pocket underneath and I didn't bring it up slow enough) and have heard some good techniques for preventing it in the future but I'm hoping to still recover this piece. I know it'll look funky but I'd really still like to try and get it into a bowl.

Does anyone have any advice or guidance? Thanks in advance!
Brad Walker
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Re: Dealing with bubble in glass

Post by Brad Walker »

In general, it helps if you give us the firing schedule you used that caused the problem.

The bubble was likely caused by firing too fast between 1200 and your top temperature. If you share your schedule we can answer more definitively.

Slumping the piece won't fix the problem. And you can't fix it by just popping the bubble and adding frit. It's more complicated than that -- you need to flip it upside down and refire, then see what you have.
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