FWIW, I had originally worked out a design in a foam-cored rudder mainly for ease of workability and for fear of having so much bronze in the water to get eaten. Two things stopped that, which was finding out how bad an idea the carbon fiber near/touching bronze would be and also finding about the effect of buoyancy and weight vs. what we percieve as part of the weather helm issue, i.e. a heavy rudder as the boat heels.

New plan is shockingly like sage Ebbster's bronze sheet idea, welded up with bronze sheet stringers inside to hold the shape and improve the tie-in to the shaft, then glassed and sheathed in kevlar and faired. This is actually much simpler than the previous plan and even simpler than constructing of plywood...the only difficult part is finding a reliable welder who is familiar with TIG welding on bronze! The form of the thing is an easy one, just a 2:1 taper...NACA foils do not belong on this type of rudder and are apparently counterproductive.

The rudder is to be counterweighted internally as well in order to try for the most neutral average helm feel possible.

I think...at long last...we are finally ready to build the pair of them.
One mod is the one-piece rudder shaft (almost 7' long!), and the Ariel type rudder shoe and support strap (straps, in my case, we're using two in the same locations as the recesses lie for the gudgeons). Here's hoping!

Dave