Has anyone used 3/4 exterior grade pine plywood for stringers . I laminated three strips together and plan on using it instead of the pine 1x10 board that is installed now. Marine grade plywood would be the best but would the exterior grade be useable for stringers. Jp

From my understanding marine plywood and exterior use the same glue,marine plywood has less voids (knot holes ) and I believe marine has one or two more plies.I think if I had it I would use it because you are wrapping it completely with glass.Just make sure any holes you put in it are sealed so water can't get in and rot it. Just my 2cents. JOHN SR

Yeah, marine ply has the 'footballs' in the knot holes so no voids. I used something called 'arauco' or something similar for stringers and bulkheads. Marine ply for the transom.

Marine ply is certainly best but a quality outdoor rated ply is perfectly acceptable to save a few bucks, that's what I used in my scarab and I have access to just about everything. I have seen manufactuers use far worse. Stay away from dimensoinal lumber. The biggest thing is prep and a quality ballanced layup.

Dave ....whats up and how yah been .

when you say exterior are you talking about presure treated? Make sure you let it dry real good before covering it in fiberglass

No never use pressure treated with fiberglass.