Stiffness of the hull in torsion

[topherdawson]

My incomplete hull is very floppy in torsion. i.e. I can waggle the bows right and left without the back end following. I can see that the completed hull will have closed rear buoyancy compartments which will be strong and stiff in torsion but from the bulkhead H1 forward, it is an open shell without closed compartments. I can see it will stiffen up a bit when complete, but it will still be an open shell.

Do these craft flex in torsion during use? Is it a problem? Vertical inner panels from the floor to the coaming and rigid decks would make closed triangular tubes along each side of the cockpit, and they could have small openings without too much weakening too much, to get to storage. It would add weight I can see.

Cheers, Topher Dawson.

[bphillip2]

Van2side.JPG (41.19 KiB) Viewed 2756 times

It gets stiff when you add the wood framing to the deck.