Plywood decking

['57launch]

I am trying to restore a boat my grandfather built and first launched in '57. It's primarily a plywood boat and there was extensive damage/rot to the bottom, which was repaired using fiberglass cloth and epoxy, what a system!
Now i'm putting on new 1/4" plywood on as sheathing/decking and am not sure the best fastening method. I'm looking at old pictures of the boat and can't see any screws or nails, is it possible to fasten with just epoxy?

[Alan D. Hyde]

1/4"???

Will that do any good?

Alan

[Pelican]

Are you replacing 1/4 inch with 1/4 inch? How big is the boat?

[JimD]

hard to tell from the description just what the 1/4 inch ply is being put on. Sure its possible to glue with just epoxy, clamped or weighted in place, presumably thickened with silica, but keeping in mind if such thin plywood isn't up to the job the plywood laminations will likely fail long before the epoxy will. That's why fasteners are usually added. Can you provide a more thorough description of job?

[WFK]

As like every one else,......one layer of 1/4"?
Depending on what exactly we're talking about here, you can no doubt use plywood and fasten with epoxy only. If you don't want fastenings, the way to go about this is to temporarily fasten by nailing through 1/4" pads or strips over your plywood then after your epoxy has set, remove your nailing strips. You could use sheetrock screws to really pull things together, but the drawback here is that they leave a bigger hole to fill.
Good Luck!

['57launch]

The boat is a 17' long lake boat with an outboard. And yes I am replacing the old dry rotted 1/4" plywood with the same. However, after reading some of these replies and a little further investigation, I am going to use some fasteners. Anybody have a strong feeling one way or another on the type of fasteners? Right now i'm leaning towards flat head brass screws.

[Tar Devil]

It's primarily a plywood boat and there was extensive damage/rot to the bottom, which was repaired using fiberglass cloth and epoxy, what a system! I'm a little more concerned with your initial statement... Did you just cover the rotting wood with fiberglass/epoxy, or did you replace the wood first?

Later,

Phil

[Bruce Hooke]

First off, just to double-check, you are pulling the old plywood off first, right? You're not trying to overlay it? It sounds like you are probably taking the old plywood off, which is the right way to go, but I just want to make sure.

As to the fasteners, this is not that critical since once the epoxy sets that should be the primary structural connection, however, if I was going to leave the screws in place I would use flat-head bronze wood screws because brass has a bad habit of falling apart in salt water. This probably wouldn't matter that much in your situation but it sure would be annoying if you had to take the screws out somewhere down the road and the head was too shot to get a grip on with a screwdriver. Another option would be bronze ring nails, if the structure of the boat can stand the pounding necessary to put them in, but, of course, ring nails are a real pain to take out if that ever becomes necessary. You could also use drywall screws and plan to take them out after the glue sets and then fill the holes. Wide crown pneumatic staples would also do the job (possibly supplemented with a few drywall screws where more force is needed) and they would also be removed after the glue sets. Narrow crown pneumatic staples would also work but they would probably get left in place so you would want to use stainless steel staples. All things considered, I would recommend going with the bronze screws. They are a bit more work than the other options but they are the most reliable way to go, especially since they will provide some long-term back up to the glue joint.

['57launch]

I actually mis-spoke, the rotted areas on the hull were removed down to good wood and filled back up using fiberglass tape and epoxy. Then the entire hull was glassed using cloth and expoxy, so the hull now is in great shape.
All the dry rot was on top, because the boat was left out without cover, so all that plywood has been removed.

['57launch]

I actually mis-spoke, the rotted areas on the hull were removed down to good wood and filled back up using fiberglass tape and epoxy. Then the entire hull was glassed using cloth and expoxy, so the hull now is in great shape.
All the dry rot was on top, because the boat was left out without cover, so all that plywood has been removed.