Building a Rudder for 23' boat

[sailingdog]

Bob's suggestion of making a good, full-size, half template of the NACA profile you are aiming for is an excellent one..and will help prevent making an asymetrical rudder that has serious steering issues.

[GaryHLucas]

Originally Posted by sailingdog

Yes, fiberglassing the rudder will add some thickness..but you will be shaping the plywood to an airfoil shape (in an ideal case), and that will remove some of the thickness of the plywood... so starting at 1.5" thick would probably be better than starting off 1/4" shy of it.

The part of the rudder above the waterline probably won't need to be shaped. So I would think he is doing right with the 5/8" plywood with 1/8" of glass over it. Also by not cutting into the blade at maximum chord I think he'll find it easier to get an accurate shape.

[fatcam]

Thanks for the post, I had been pondering that as I draw very close to starting my project, and I had come to the same thought. I at least have a really good picture of my old rudder as I took some when I scraped and painted the bottom and rudder. That's what got me thinking. I appreciate everyone's tips and suggestions.