Is the puzzle joint curved to accommodate better bending characteristics or to provide more edge gluing surface or both?
The puzzle joint is a substitute for a scarf joint that happen to be easy to cut with a CNC machine. This boat will be available as a kit.
The goal is to smoothly transfer any forces applied on one side of the joint, to the other side with minimal stress at the joint. The joint will have increased stress wherever there are sudden transitions.
So, the goal with the puzzle joint shape is to minimize sudden transitions. Straighter lines are bigger stress risers, so I tried to avoid straight lines. Tapering parts transition the load gradually, so I am trying to create tapers.
I am also trying to come up with something that is visually interesting. Some sort of joint is required and they will be visible, might as well make them interesting.