I've gone super-low-tech. The rudder is a 2 x10, doug fir, five feet long, crudely shaped with circular saw and surform plane to something vaguely approximating NACA 0045a.56 sub pagaraph 6b. In other words, thick at the front and thin at the back. I bought shaefer J-24 size hardware and bolted it on.
Yeah, it weighs 7-8-9 pounds but it cost next to nothing, and took me two nights in the garage with no-tech materials. To lose 5 pounds and make a really light and hot rudder would cost a lot more and take a lot of time. The theory is that I'll never use it, right? This is a get-the-boat-home rudder.
1968 Selmer Series 9 B-flat and A clarinets
1962 Buesher "Aristocrat" tenor saxophone
Piper One Design 24, Hull #35; "Alpha"