Re: Exterior wood finish
built my splashwell and casting platforms from birch ply , the stuff sold at home depot.
Unless its really completely protected it will not hold up, edges have to be resin soaked especially. Try about 6 coats of poly resin on the exposed edges and let it really soak in, keep applying it til its completely saturated and filled to a smooth finish when cured.
on the flats I applied 3 coats of poly resin, 1 coat didn't do the trick at all.
those wood "treatments" are ok for interior work, galley etc, but you need a physical barrier if its exposed.
I like the finish of that wood however it is not exterior grade wood.!
But I can tell you, if its done right with the polyester it looks very decent.
I didn't use any cloth except at the joints for reinforcement.