If you search the Forum for Kirk Fredericks or maybe Farback you will find his download for full size frames. If you search "Sea Flea" you will find discussion of stringer lengths (there is no fixed length, you just make it look right). If you search Ric Moodie you will come across some posts I made re the Sea Flea I made last summer. It is easy and fast to make. I chose a length closer to 11' because then I could build it from a 12' plank.