Warning: Got a stuck blowpipe from a cold punty weld and nearly lost a piece

Was working on a vase at the bench in Portland last Tuesday. I attached a fresh punty to the base, but the shop temp was around 60 degrees and I think the weld was too cold. Went to crack off the blowpipe and the whole piece twisted sideways on me. The glass was still hot enough to sag and I almost dropped it on the floor. Had to reheat the neck carefully and use a jack to break the seal. Anybody else deal with a cold weld ruining a piece mid-shape?

2 comments

2 Comments

brookef732d ago

Man, cold welds are a pain. The thing nobody really talks about is how the shop temp messes with your punty more than your blowpipe. A cold punty weld on a hot piece creates a stress point right at the base, and that's where the twist happens. You need to warm that punty up in the glory hole before you even touch the piece, not just dip it in the marver. I've started keeping a small torch on the bench for exactly this reason, just to hit the weld area for a few seconds before cracking off. Saves you from having to reheat the whole thing and mess up your shape.

max_jones2d ago

Funny you mention that, my buddy Stan used to preheat his punty in the microwave till someone caught him.