TIL a cheap harbor freight heat gun can fix a small crack in a punty seal

I was working on a small vase last week and got a hairline crack right where the punty attached. My usual torch was too big and hot for the spot. I grabbed an old heat gun I use for shrink wrap, set it on low, and slowly warmed the area for about two minutes. The glass smoothed out and the crack sealed shut without messing up the shape. Has anyone else used a heat gun for small fixes like this, or is it a bad idea for bigger pieces?

2 comments

2 Comments

umamurphy2d ago

My friend who works with borosilicate tubing uses a heat gun for annealing small joints. He sets his to 750 degrees Fahrenheit and moves it in slow circles about an inch away. The key is letting the glass cool in vermiculite, not just on the bench.

the_hugo2d ago

Heard a guy on a glassblowing podcast say he uses a heat gun for touch-ups on lampworked pendants. He said the wider, softer heat is perfect for when you just need to relax a tiny stress point without blowing out the detail. Definitely seems like a solid trick for small stuff, but I'd be nervous to try it on anything with much thickness. The slow heat probably avoids thermal shock better than a pinpoint torch flame in some cases.