I'm aiming this question to Jerry since he was the designer but anyone...feel free. I'm making a new rudder for my M12. The old one is great but I'm making a fold up one and I'd still like to keep the original. I like learning these things so that's part of the reason too. It's fun messing with splinters and fumes. Anyway, I was going to make something along the lines of a Naca 0012 as that seems to be a popular foil - not to racey but not a pig either. Measuring the original rudder it doesn't look naca anything but the thickness to chord length ratio seems really small...about 8.5%. Literature suggests that this rudder may stale alot without constant attention. I never felt that way about it while using it so I guess I'm just looking for some clarification or understanding. Any thoughts on this? Considering the wood I'm using is a little thinner then what I wanted my rudder may end up closer to a 10% ratio. Again thoughts? Ok, I know, I know that all this detail really doesn't matter since there's no M12 class to be racing against and my dad has said it's pretty hard to screw up a rudder. I'm happy to know the tolerances are fairly forgiving but I'd still like to understand the theory for doing it right and even understand what and why behind the original rudder design. Thanks Jared