"Brian D" wrote in message
news:y_rpc.54753$xw3.3275430@attbi_s04...
In the book Devlin's Boat Building, Sam Devlin states that boats over 90'
have been built using these methods.

Brian

When I think of Plywood composite boats I think of plywood as the core
material for a fiberglass lay up. Plywood is stronger than most cores and
this strength is probably use in the structure of the boat so it is
important that it remain dry an rot free. Not easy things to do over a long
period of time. As long as it retains its structural integrity you can dry
out cores by drilling holes ever few inches and vacuum bagging the hull
until is stops loosing weight. The hot summer sun will help.

As a core material plywood is a pretty good one it is inexpensive, strong,
reasonably easy to work and not subject to catastrophic failure that plagues
some other core materials when they encounter slamming loads.

Even better is veneer that can be treated with a borate solution to rot
proof it and laid up with epoxy to water proof it for a lighter, stronger
more expensive and more durable core.

Gordon