Waterproffing is not the problem here. Pretty much ALL plywood is made with
waterproof glue. Marine plywood is about the highest grade of plywood due
to it's ridgid spec requirement. Most plywood contains numerous cracks,
voids, and large knots in the interior laminations. Often they will be
repaired on the outside layers only. Marine plywood has very few cracks, NO
voids, and knots must be under 1/2 inch. Pay the extra money and only do
the job once. Cut this cost corner at extreme risk of failure.

Jon


"Pop" wrote in message
...
Has anyone used the 1/2 in. plywood from China, Home Depot has this but it
is interior grade, colud it be used for boat building if it was completely
sheathed in a waterproof material.