Waterproofing door panel

[Granitedrop]

I’m planning on starting my build this summer. My plan has my door made out of 3/4 plywood. I want to keep it “bright” meaning the wood grain showing. I’m looking for opinions on how to best achieve this. My first thought is epoxy and a single layer of 6oz fabric. I’ve used polyurethane resin on a canoe repair but hear it isn’t favored. I also have read about “the mix” on this forum. Would it be sufficient to protect the plywood? Other thoughts? Thanks!

 

[Tony Latham]

Epoxy/fiberglass it with 4-6 oz cloth and then coat with spar varnish for UV protection. Polyester resin will leave the color of the goo and won't adhere like epoxy.

Tony

 

[Granitedrop]

Thanks! That confirms my initial impulse then.

 

[Pmullen503]

Do both sides to prevent warping. You want both side to be equally "waterproof". Really what you want is both sides of the plywood to absorb and release moisture at the same rate.

 

[Granitedrop]

Definitely. Is there a concern that the sheet might warp in the process of applying to one side? Do I need to apply a light coat of epoxy to both sides before I start laminating?

 

[Tony Latham]

Is there a concern that the sheet might warp in the process of applying to one side?

Nope, but I agree, doing both sides is a good idea. You should probably do the other side the next day.

Tony