Glue Sealing Exterior Ply Edges

Re: Glue Sealing Exterior Ply Edges

Tom Norton

My thinking is to "waterproof" the dge. Solid hide stain will be the final finish.

Re: Glue Sealing Exterior Ply Edges

Don Stephan

I have sometimes wiped latex caulk into the plywood edges to try to fill voids, before painting.

Re: Epoxy 100%

TomD

Assuming we are talking about some grade of wooden boat epoxy, it will be superior to anything else you can use. Plywood edges are made up of 3 materials, endgrain, side grain, and glue. Epoxy will penetrate or bond to all 3, and boatbuilding epoxy is actually formulated for that purpose. It will sink deeply into the endgrain, which is the main thing that will suck in the water. Sidegrain, not so much.

There are different grades of epoxy for this purpose. If you are doing this as an afterthough/overkill, then basically anything marine will work. If you want it to really help add longevity to your structure, you need to consider something like WEST, RAKA, MAS, or other at least 2-1 formulation, not a 1-1 formulation.

It gets more complicated if you have a bunch of materials you are dealing with. If you have frame and panels, with solid wood that needs to be dealt with, or metals, or vinyls.

I had a door that rotted away from ground contact. Damage up to a foot off the ground. The framing lumber in the door was fine. So rather than do a door replacement, I just scarfed in new plywood, then I wrapped in fiberglass. Another option is to build up a thick layer of epoxy where the door meets the ground. Form a trough in the lower edge and coat the wood, then level with epoxy putty.

Titebond is not designed for this purpose. I haven't used the 3. I have a lot of experience with 1, and with other similar glues. Basically they cure through evaporation which provides pathways for moisture. They are hard to finish (you can test this with your specified finish). There is probably some kind of primer, maybe for PVC pipe that would work. I know it works to get epoxy to stick, but why bother.

A better bad option would be poly glue, or even poly construction adhesive. A material that is good is 3M 5200, but unless you have an open tube, I would not go there myself. With 5200. you could even bond a wear strip of plastic or metal to the bottom of your door. If you ever watch shows like Bering Sea Gold, you have possibly noticed their DRYsuits (which get a lot of wear due to crawling on the ground) are repaired with some white stuff. That is 5200.