Dave: it depends on what type of clearcoat you use. If the clearcoat stays on and seals, there is no way the paint underneath is comming off. Alot of time in custom car paint jobs where there are some sketchy things and decorations that they are afraid might not stay on they will put an extra clearcoat on the outside to seal everything in. Anyway, i'm not recomending spending the money to clearcoat the rudders, its just an idea. I personally dont bother to paint mine at all.