solvent-based removal of old window putty
So after all the reading and thinking and hemming and hawing (yes I've over-analyzed yet another project!), I re-glazed my first window. I used oil-based primer and Dap 33, and it went reasonably well. I told dh, the glazing was easy, it's the prep that was killer.
The single hardest thing was getting the old glazing out. Looking around at options, I've seen physical and heat-based options:
Prazi drill bit
dull chisel and 5-way tool
heat gun (20% glass breakage or more)
steam and heat softening (John Leeke's video, he claims 4% breakage)
What I wondered was, what about a solvent-based option? But what would dissolve old hardened glazing? Turns out, old hardened glazing is basically dry linseed oil and lime that has more or less turned back into limestone (OK I'm hedging there, but that's my best info.) Apparently the solvent for dry linseed oil is....linseed oil. And the solvent for limestone is...bleach? I'm not so sure about the second one, but I trust the first one.
So, I'm going to test this out and report back. But I just wanted to share what I've found with the forum in case anyone else has already tried it.