Rudder Refinish and Eventual Rebuild

I'm going to just refinish the rudder for this next sailing season with the intent to eventually build a new one. This is a homemade replacement out of mahogany. The original was hardwood covered with fiberglass. They tended to break and indeed this original one did.

Since its January 2, 2010 and 14 degrees F outside, I'm looking for things to do inside, so I brought the rudder in and started sanding it.

It was originally finished with varnish of some kind. It looked great originally I'm sure, but the varnish can't hold up being in water all summer. So I've ordered Interlux VC-17m anti fouling bottom coat. Its brown so maybe it won't detract from the appearance too much. I'm leaving the top half just finished with varnish. You can see the blue tape where the brown will stop in the photo at right.

I'm filling some of the dings in it with automotive spot putty. Maybe I should have gotten some epoxy but if the paint I've ordered is what it should be spot putty should be OK. Also, since my long term plan is to build a new rudder that looks like the original, all this putty and paint have to last is this next summer.