Sandy bought a very old bentwood sewing machine case, destined to keep the dust off a very old sewing machine. The case looked (mostly) in good condition:
The end where the lock is located looked good, even though there is some damage to the veneer – it has a hole that allows insertion of a key, to lock this top to the bottom:
Some damage is apparent when the case is turned on its side – the veneer layers have partially delaminated from the end of the case. On inspection it appeared that hot hide glue was used to apply the layers of veneer – very brittle, and softened by water:
The screws securing the lock required a little manipulation, but I was able to loosen them to remove the lock:
I had already re-glued the veneer at the other end of the case – but this side was easy:
When I removed the lock I weighed the options on how to proceed.
The problem: a large hole that accepts a key, to allow locking the top to the base.
Why is it a problem? Because any glue used to repair the veneer will seep through the hole into the mortise for the lock.
Options: I thought about using a wooden plug, or a cork plug, etc.
Sandy’s solution was brilliant: use foam to keep the bulk the glue out of the mortise during the glue-up.
That is what I did. I used thick wooden cauls, to distribute the clamp pressure evenly along the edge – they are wrapped with packing tape, to prevent the liquid hide glue from sticking to them:
Late yesterday I replaced the foam layers, as just a tiny bit of glue had seeped through the hole into the mortise. I will find out later today how well this repair turned out. Please stand by!
Glue used: Titebond liquid hide glue.
My best guess about the glue used originally: Hot hide glue.
— Al Navas