inexpensive plywood

[indianbayjoe]

It appears that there is just a layer of some sort of resin or varnish. No cloth evident. That can be filled with some thickened edpoxy then covered with cloth or bi axial and it should be fine. Don't put the old piece of wood back in.

[lewisboats]

A little history on the wood. It has one quick coat of epoxy...it was applied basically days before I took it on vacation last summer and wasn't at all finished. It saw plenty of water over two separate trips last summer and I ended up dumping it once when the running rigging jammed and didn't spill wind fast enough. I will take PAR's advice and put some heavier cloth on it than I had planned but it is currently sitting in the Garage with a pile of stuff on it as it is still too cold to work on it. I took the picture to show how it separated from the glue line and how it checks...the fix is not hard just a bit more sanding and some more epoxy.

[Boston]

the only material that expands and contracts like wood is wood, so why would anyone suggest substituting a large chunk of epoxy for wood when uniformity of movement is key to stability and therefor longevity. Sorry to be the detracting party on this one and I'm sure I'll be land blasted for it but if you want anything resembling a homogeneous surface or of uniform flexibility then it seems reasonable to maintain a consistent product of a single material, IE thin layers of glue and laminated of wood. The moment you substitute a chunk of wood for epoxy you loose that uniformity and therefore the consistency of motion. Its like dropping a 10 inch boulder in a 1 inch aggregate mix. I may be the dissenting opinion in this one but I'll take it to my grave. either carve out a chunk of laminate and replace it or glue back in the defective piece if you want anything resembling the original flexibility, otherwise you beg a deformation over time.

[indianbayjoe]

I think bostons reply holds more true for planking than it would for plywood in our experence. Over the years anytime we have seen a patch like that in a planked boat, sometimes it might pop out or come loose on one side due to improper preparation but not so much on say a plywod lapstrake hull where a small patch was needed. The plywood moves a lot less and were in an area where over the year the weather certainly changes. The thickened epoxy seems to work well for us in those situations. There is nothing wrong with inserting a wooden plug properly epoxied though.

[Steve W]

While there is no reason not to glue back in a piece of veneer, unless you are going to go to the trouble of scarfing all four edges of the piece you dont end up with a better (or worse) repair. Most people will just fill it with epoxy and it will be fine, especially where you are going to sheath over it with fabric.
Steve.

[lewisboats]

Hey folks...look at the picture again...the so called chunk is about 1/4 inch wide and maybe 1-1/2 inches long and a hair over 1/16" deep. Some thickened epoxy to fill and a sheathing of glass and that ain't goin' anywhere.

[PAR]

Encapsulated wood, doesn't expand and contract to environmental changes, regardless of it being solid wood or plywood. There are several reasons to reuse a hunk of wood that has been knocked out, but most of these reasons are aesthetic or material saving in nature.

Plywood is a wood product, much like cheese whiz in a can. It's made from cheese, but don't get confused about the differences. Plywood is the same deal and not subject to the same issues that solid material is. Yes, it still can suffer the same indignities, but repairs and the way it reacts to these things are different.

Unlike solid wood Dan, plywood can tolerate a hunk of plastic embedded in it's surface. In fact, taped seam construction techniques employ this technique on the edges of plywood routinely, without issue. This is because of the manufactured aspect of plywood, which gives it it's dimensional stability. Unlike solid wood, though it will move with moisture content changes, this movement is so slight in comparison that it's a non-issue and divot repair with epoxy is perfectly suitable.

You are correct in that a solid wood piece should be repaired as you describe, unless it's encapsulated (stabilized) or an engineered material (sheet goods or lamination).