Posted by Karl Mattson (128.143.139.62) on August 03, 2003 at 15:08:06:
In Reply to: New rudder for wing keel posted by Daniel Tradal on July 30, 2003 at 17:24:49:
Dan --
I had the same issue and fixed it last year. The problem with the stock rudder for the wing-keel version is that it's unbalanced and has way too much surface area on the upper, trailing edge of the rudder. The latter is primarily what accounts for the excessive weather helm.
Solving this problem is a matter of taking surface area off the trailing edge and adding it forward of the post. A general rule of thumb is that 18 % of total surface area forward of the post will balance a spade rudder. 18 to 20. Also, if you don't mind losing the 3 inches of gimme-space keeping the current rudder slightly above the keel, getting more surface area lower in the water also helps a bit. The more high aspect the foil is the better. Of course, you can only go so far with a wing keel.
Still, I believe it was well worth the effort and expense. It has made a big difference, particularly with handling in reverse and in close quarters.
There are several postings on this process on the board. Please feel free to contact me via email if you want specifics.
cheers
karl