DRY PLY VRS. OUTDOOR GRADE PLY

[Baxter1982]

The only kind of plywood I can get around where I live is either dry ply which has a waterproof sealant on it or the outdoor grade plywood which has a sanded finish on one side... I'm needing the ply for the transom and flotation boxes, you can see my thread http://www.bbcboards.net/zerothread?id=659515 My concern is that the glass won't stick to the waterproof coating... So if anyone out there knows about this please help me out and let me know which one to use and why.... Thank you all so much....

[BASSCAT7]

You cannot use the DryPly plywood. It has a waxed based coating on it for the water repellency and that would not allow a good secondary bond with the resin/mat.
If you can't get marine ply the outdoor ply will work, just try and find a piece without too many voids in it.

[Baxter1982]

Basscat you've saved me again....

[tjonas1]

Im using the indoor project plywood for my stringers and transom. You can get it at Lowes or Homedepot. It is a sanded plywood and has very little knots or voids. The 3/4 runs around 29.00 a sheet here in VA.

[mideerslayer]

i used dryply last year and had no issues with fiberglass not sticking to it

[BASSCAT7]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by mideerslayer &raquo;</td></tr><tr><td class="quote">i used dryply last year and had no issues with fiberglass not sticking to it</td></tr></table>

Well good luck with it. Hope it holds up well for you.

Did you sand down the plywood before laminating it ?

The Water Repellent Coating they use on the Dry Ply is a Latex-wax emulsion.
Wax and Resin do not mix well together.

DryPly is made for use in sub flooring and sub roofs, and from what I have seen on it they recommend that it not be painted.

[slinkeey]

Why do you want to sand the plywood?

Wouldn't a rough surface give the resin something to grab onto?

[Baxter1982]

dry ply is not rough.... it is sanded and has a waterproof finish on it...

[BASSCAT7]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by slinkeey &raquo;</td></tr><tr><td class="quote">Why do you want to sand the plywood?

Wouldn't a rough surface give the resin something to grab onto?</td></tr></table>

I was referring to the DryPly only. Wondering if he sanded the coating off the wood to get a better adhesion surface.