Thread: How to undo glue?

I see this thread is quite old, with no replies, so hopefully you have sorted this out now. It would be interesting to see photos to be able to assist you better. Around 30 years ago (i.e late 1980s to 1990) the most likely adhesive would have been PVA or epoxy I think. The wonder of hide glue had been lost by then (though renewing new). A lot of water will soften the PVA (and remove most finishes) but epoxy is non-reversible as far as I know.

What style are the chairs? I once, in ignorance in the late 70s, got saddled with some repro cedar ballon-back chairs. They were ghastly (in hindsight, with much improved knowledge) and definitely glued with PVA. Around that time there were some repro rail-back cedar chairs made by a company started by John Buttsworth. They would have a label on them to that extent. He was a knowledgeable collector and, though I have no certain knowledge of what adhesive they used, there is a chance that hide glue was it. I was repairing antiques with hide glue back then so it was available.

There's quite a spectrum of different chemistries in modern adhesives, many far beyond straight woodworking (construction adhesives.)
The hide glues are still the glues of choice in the musical instrument business. I know of at least 4 different ones.
The biggest supplier has been Stew-Mac (Stewart MacDonald.)
Just today, I got an email from Lee Valley with their newest luthier's catalog, including hide glues.

My understanding is that Titebond 3 dries to a brownish colour. If it is then it is not water resistant/proof????

Titebond wasnt available here in Oz back then.
H.

Everything can be undone, its just the collateral damage that is the issue.

Adhesive De-Bonding | Removing Adhesives | Adhesion - Permabond

Have a quick read.

Originally Posted by gnu52

Hello,
Someone has sent me a chair in the hope it can be repaired, part of a reproduction set made in cedar. It is certainly less than 50 years old & probably more likely 30. Country of manufacture unknown.
The leg is glued to the rails using m&t joints, not very tight. It is necessary to undo this joint to make the repair.
The glue is the colour of milky coffee is inclined to flake off where it is accessible. I have tried using a hot air gun, not successfully.
My next attempt is probably steam or hot water to penetrate the joint.

Any other suggestions?
Thanks, Bill

the glue is possibly resorcinol formaldehyde -- I'm not sure that anything short of a really big hammer can break a resorcinol formaldehyde joint

Hello,
Ended up using a heat gun, wrapped the job in a wet rag & heated to the max.
Cleaned joint with small hooks, solvents no help.
Needle & syringe to replace glue.
Holding so far
Regards, Bill