Re: 1/8" ply repair on a 1958 dinghy
I'm curious, what design dink is it? Is it flat or round bottom?...glassed only on the outside? Back in the plywood boat days quite a few dinks and skiffs were made from exterior ply. With that came the ocassional blister/delamination/bubble or whatever boatheads want to call it. It wasn't considered a big deal and repairs endured long lifes...of course long life for a plywood boat in my neighborhood was only 10-15 yrs if painted every year and rainwater kept from standing in it. If left outside holding water it was maybe 5yrs max. Epoxy was in it's infancy back then and wasn't big in the boat repair picture either.
The way I learned to fix (and did) these was cut the area out from the inside, leaving a generous area around the delam to remove compromised wood, let dry a couple weeks, bevel on the inside (no bevel needed these days if you use epoxy) the edges back about 5times the thickness of the wood, make a wood patch to fit and glue back in. Finish the exterior with a glass patch. A repair like this is flush on the inside and outside...and can be hidden inside with normal primers and paint.
Getting the wood dry is the deal killer on patching and plywood likes to wick in. There are ways to help it get it dry. It's expensive but K2r is an excellent product that sucks water and oils out. It's about half acetone with another evaportor type cleaning fluid, talc and corn starch. Spray it on the raw wood, let it sit a few minutes and dust it off. Repeat until it doesn't wick. Let sit overnight and treat again. Plain acetone can be used but it doesn't draw moisture out like K2r (K2r is lightyears better in drying water and removing oil than plain acetone). Cutting the bubble out with an exacto, drying and filling with epoxy/glass should work too...It's way easier...but my concern in just digging the bubble out would be getting it dry.
1/8" ply or 1/4"?
bp
