Waterproof plywood

[Dave-R]

Hello all; I am reupholstering some seats and a sundeck in my boat. I need to replace the plywood on the sundeck. I bought a sheet of 3/4" CDX plywood and I wondered if I need to seal the plywood. If so, what do I use to seal? Thanks, DaveR.

 

[wellcraft-classic210]

Re: Waterproof plywood

It will last longer if you can seal it. Thier are many choices.


I brushed all my pieces with epoxy ( 2 coats on end grain ) and was happy with the outcome.


The experts here will probably have something to add.

 

[Woodonglass]

Re: Waterproof plywood

Yep Epoxy is great for sealing the wood. If you maintain your boat well and keep it covered during the offseason, you could just use Rustoleum Oil Based Paint, Thin the first coat 50% with Mineral Spirits so it will really soak in well, then follow up with 2 - 3 full strength coats. With proper Care that will seal the wood for many many years. Easy to touch up later if need be.

 

[fishrdan]

Re: Waterproof plywood

How well is the boat going to be maintained in a dry environment, it's pretty dry up in Nephi, right?

I'm in Vegas and did the Rusto paint sealing that WOG suggested and the plywood still looks great after 3 years, no checking or delamination of the plywood. I hose it out a couple times a year, it sits out in the driveway covered, so while it stays fairly dry, it does get a good dousing of water every now and then. If you were in a wet/humid environment epoxy would be best, but Rusto will probably work just fine (as long as you don't leave the boat soaking wet). A couple things to consider;

Rusto = cheap
Epoxy= expensive

Rusto = good bang for buck protection
Epoxy= best protection

Rusto (3 coats) takes a long time to dry (a week so it doesn't scuff easily, a month before it's cured and hard)
Epoxy cures quick

For the leftovers-
Rusto you can use for a lot of other things that need a coat of paint
Epoxy has limited uses

 

[Woodonglass]

Re: Waterproof plywood

You can buy and add a hardener to the Rusto Paint to make it dry to the touch in about 4 hours and cure in a week. If you have a Tractor Supply near you they carry Majic Paint that has it's own Hardener, Reducer and if you want Clear Coat. Basically the same paint as Rustoleum. Same Price too!!!! This link has some helpful info..."Paint Your Boat for Under $100 Bucks"

 

[fishrdan]

Re: Waterproof plywood

I wished I could have found that hardener in my area when Rusto'ing my projects, I tried, but couldn't... :grumpy:

 

[a1964rn]

Re: Waterproof plywood

I like to use Spar Varnish. Lowes has it for less than $15 a quart. Just brush it on and you're done.

Shop Cabot 1-Quart Spar Varnish Gloss at Lowes.com

 

[matt167]

Re: Waterproof plywood

I wished I could have found that hardener in my area when Rusto'ing my projects, I tried, but couldn't... :grumpy:

Finish 1 brand hardener is available at Napa. Any Iso hardener will work in Rustoleum/ common Alky'd Enamel. I have even used leftover PPG hardener in rustoleum with good results.

 

[fishrdan]

Re: Waterproof plywood

Finish 1 brand hardener is available at Napa. Any Iso hardener will work in Rustoleum/ common Alky'd Enamel. I have even used leftover PPG hardener in rustoleum with good results.

Good info there! I have almost a whole bottle of automotive paint hardener left over (had to buy a whole friggin pint for a transom re-paint), but not sure what type of paint/hardener it is off hand.