Repair blisters in mahogany veneer

[Don Hein]

I am preparing a 40-year old Singer sewing machine cabinet up to the point of refinishing. It is largely made of 11/16 mahogany ply. The cabinet backside was apparently exposed to the sun over time, and there are several small blisters in the veneer surface, which runs vertical. These are up to 1.5" long and maximum 3/4" wide, and not more than 3/32" raised.

I am considering using a fine medical hypodermic. I would thin my Titebond just enough to pass through the fine needle in order to load the hypo, then inject the glue into the blister. Then I would weight the blister area with something heavy and flat over waxed paper. The blisters are too far from an edge for clamping.

Will this solve the problem? Should I slit the blisters to help flatten them?

Any thoughts/alternatives are most welcome.

Don

[Lee Schierer]

Pushing PVA glue through a diabetic type syringe requires lots of thining and the holding power is reduced. A larger 8-10 gauge needle can be pushed into the wood like raising a chip to hide a nail pretty easily.

[Cliff Rohrabacher]

PVA will Bleed through. Thinned PVA should REALLY bleed through

I'll bet it won't stick anyway cause the original glue is prolly Hide.

Can you get some hide glue?

[Thomas Knapp]

Is there any way to see what the original glue looks like? If it is Brown and fairly transparent it is hide glue and that would make it easier to fix. Hide glue will reactivate and stick to old hide glue. You could use either the liquid hide glue or hot hide glue. If the weight doesn't keep the blister down an Iron set on cotton will reactivate the glue heat it with the iron and roll it down with a wallpaper seam roller.White glue will also soften with heat and may stick down a blister. Slitting the blister may help get the glue under the veneer and help it lay flat.

[Frank Drew]

Don,

You could try to reheat/remelt the old glue; if that doesn't work use new glue.


Slitting the blister may help get the glue under the veneer and help it lay flat.

I agree, then some way to apply localized pressure.

[Ed Howe]

I tried this (hypodermic needle and thinned wood glue), after trying unsuccessfully to reactivate the existing glue, and it does require a lot of thinning as Lee pointed out. My results were not all that great. Another thing I tried was to take a sharp x-acto knife and cut along the bubbles, with the grain, and insert some full-strength glue. I got mixed results with that as well. The cuts aren't noticeable, but I still have some slight bubbles.