Breaking glass while soldering
by Nicole Deslandes
I am soldering a large copper foiled panel.
What can cause breakage? I have two broken pieces and don't understand.
The breakage happened about 10 inches from where I was soldering at the time. I know that too much heat will break the glass, but from 10 inches away?
I am very upset because those two pieces are very intriquate and will be hell to replace.
I put everything on hold and won't touch it for a while
I don't want another broken piece if I am doing something wrong.
Thanks for your help.
I can't believe you're doing anything wrong with your soldering, I believe it all started at the cutting table.
Most often the breakage is cause by a small fracture in the glass that happens when you break it out. It will be so small that you won't see it until it starts to run during soldering.
Tapping is one way to cause these fractures. If you do tap the glass, I'd recommend using running pliers instead. There are very few cuts that can't be run with running pliers.
You mentioned that the pieces are very intricate. Did you cut them out with a saw or a glass cutter. If there are extreme angles, the glass will eventually run just because glass likes to break in a straight or gentle curve, not an angle. This is very true when using a glass saw. The fracture won't start to run until you start soldering.
You said 10 inches away. It may have started running when you soldered that area (still invisible to you), then continued as you moved the panel during the rest of the soldering.