how to unglue for a repair?

[Benjimin Young]

I posed this question in a different way on another section and then it dawned on me that repairing instruments must sometimes require careful and tricky disassembly of glued parts. So I though someone in this group might know a trick or two for weakening wood glue prior to applying force for disassembly. In my case it is an oak cabinet door I'm trying to disassemble not an instrument but hopefully the tricks can be borrowed.

[Mel Fulks]

Good idea in theory . Instrument makers use weaker glue for parts most likely to need later disassembly . The glue on the door ,even if rated for interior use only ,will surprise you with its resistance to water. The sharp hammer blow is probably better.

[Sam Murdoch]

Very unlikely that you will be able to disassemble the door without setting the entire thing in a bath of warm water. More harm than good and probably not successful. You still need to resize the panel and the stiles and then reassemble. To what end? To save the finish? If you have the capacity to remake the panel and then build a door frame in some manner then simply bust/saw the frame apart - resize one edge of the panel and build a new frame. Less work in the long run. Easier to finish the new frames than to try to blend in to the old finish IMHO.

[phil harold]

heat will soften many wood glues

[Earl Sullivan]

Luthiers generally use hide glue, specifically because the joints can be broken relatively easily.

Then you use a hot knife and work very slowly and very carefully.

[Kevin L. Waldron]

Silicon Heat blanket will work wonders on most glues........... hide glue.... between 150 and 200 F to loosen...... PVC style glue...... 200 to 300..... ( usually 240 ) Water Proof PVC's around 275-350 and most epoxies..... 250 - 400........ haven't seen much that heat want loosen.... Reciprocal glue is one of the harder to get to turn loose..... but I doubt the doors where made with this..... Probably PVC... (Elmer's, Titebond)

Blessings,

Kevin

[Jim Creech]

On instruments the go to stuff that always works for me (except on epoxy) is hot vinegar. I take a lot of instruments apart for repair.

[Bradley Gray]

I have an old clothes iron in the shop for such occasions. Permanent press setting will loosen titebond type glues. If that fails, I cut off the tenon with a hand saw - a new tenon can be mortised in once the door is apart. This may sound radical but it works and it leaves the finish intact.