I have one of the variants of plastic rudders and I gave a best attempt at painting them when I painted the rest of my boat. I used Interlux Pre-Kote for primer and Epifanes Mono-Urethane for the top coat. At one point the Pre-Kote didn't adhere very well and I had to sand it off and stat over on at layer. Once I was happy with that I didn't have any issues with the top coat sticking to the primer. I only had it in the water 3 times at the end of last season after I finished painting and no issues yet. I guess time will tell. I have another set of fiberglass rudders that I have bought since I finished painting, and plan to paint them as soon as at gets a little warmer out.
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Catamaran Racing Association of Michigan - Marketing Officer
USF18 - Social Media Manager
2010 NACRA Infusion
2004 F18 Hobie Tiger - SOLD
Hobie 16 - BREAKPOINT - SOLD