Thomas Wentworth wrote:
I was looking at a site that showed a home builder's sailboat. He had some
plans, set up a frame on the ground and made a cross piece frame ..

He used plywood to sheath the boat. Epoxy on the plywood.

Two things ... when building a hull, do you first need a backbone,,,
keel,,, or whatever??

Another ,,, if you use plywood, can you glass over the ply and the ply
becomes a core?



Bolger's "Instant Boats" (books and plans available from H.H. Payson, )
offer an easy construction method that does not require lofting (Look
into this if you plan to build a traditional boat -- means drawing the
plans full scale so that you can find the mistakes in the measurements
given in the published plans and so that you can make patterns for
actually building. Many first time builders get so discouraged in the
lofting phase that they never get to the actual building phase.) or a
strongback (the cross-piece frame).

BTW, traditionally, what you are calling a frame is usually called
"molds" (or "moulds"). In traditional terminology, frames are a
permanent part of the boat.