If the joints are properly done, they'll be about as strong and stiff as the
stock. No beefing up will be needed.

Patrick wrote:

I need to scarf 3 sheets of half inch ply together before I can start
lofting, for a stitch and glue boat I,m building.
How strong is the joint once glued and will I have to beef up the joint with
battens to enable me to handle the ply once together?
Patrick
8-1 was the ratio I was going to use.