non-toxic waterproof ply

[Andrew Gabriel]

Need to replace plywood bird table top. I already have some ordinary plywood -- is there any varnish which will make this waterproof enough to use outside without peeling apart (as the current one has)?

[Andy Dingley]

Kids' poster paint on the top surface, epoxy resin around the edges. As always, water gets in through the end grain, and in the case of plywood through the inter-lam gluelines. Seriously though, you can use almost anything on top, but do those edges well.

Then make the edge lip so that the corners are gapped and give it a slight slope so that water doesn't pool.

[Rad]

Dear Andrew What is wrong with "weather and boil proof" [WPB]? There are no chemicals classified as toxic in it Chris

[Bob Mannix]

It's just the name on the product, it isn't at all really. Bit like 100m water rated watches. Personally I would use marine ply and seal the edges (or just use the cheap stuff covered as suggested, and replace every now and then).

[dennis]

What's wrong with them? You don't think the 100m is something to do with the depth do you? It isn't.

BTW I used some chipboard to make some temporary shelves in an aviary. They only needed to last a bit so I wasn't worried. I chucked them in March after being out in the weather for three years and they were still sound. I have no idea where I got the stuff but it must be all resin.

[Bob Mannix]

Err no, that was my point - do you deliberately argue with people no matter whether they agree with you or not?

[Andy Dingley]

Always had you down as more of a belfry chap...

[Andrew Gabriel]

The bathroom grade chipboard is like that. When I moved in, a block wall was soaking (shower leak), and the skirting and carpet grippers in next room all rotten, and thus presumably like that for years. The chipboard floor on which the wall was standing had a large wet patch and larger stained area, but that's all still rock solid.

[PCPaul]

But the 100m *is* a proper tested (well, designed and sampled) value - the fact that most people don't understand the concept of static pressure isn't a reason not to use it. Although maybe it should be.

But imagine a world dumbed down to the point where *everybody* understood everything. Yuck. You could say goodbye to cars, the Internet, TV etc. etc.

[Andrew Gabriel]

What type of paint is kids' poster paint? I would have guessed it's something designed to wash out, but that doesn't seem to make sense in this context.

Cheers.

[Steve Firth]

Flowcoat it with epoxy (not polyester resin), then carnish it with polyurethane. I've had a WBP plywood hatch treated that way on my boat for the last twelve years, it still looks like new.

[The Medway Handyman]

ROFLMAO!

[Martin Bonner]

I think Mr Dingly was trying to suggest that the paint on top doesn't need to have any water resistance at all. It's all about whether the endgrain is protected or not.