"Mike" writes:

Can you use any kind of plywood for boatbuilding ort does it have to be
marine ply? Surely if you are planning on glassing and painting a plywood
hull it wouldn't really matter?

If you are going to use it in the hull, marine ply is the only way to go
since it has no voids and can be bent in a continuous curve which other plys
will no properly do.

If you are talking structural core material such as bulkheads, floors and
sub soles, that's a different animal.

I used 140 sheets of 1/2", 4 ply, CDX plywood sheathed with 50 oz of knitted
glass and epoxy to build my boat.

In my application, could give a hoot less about the voids since the ply was
strictly core material, the glass carries the load.

HTH

Lew