[TaylorC]

I never see painted shafts, so I don't think you forgot to do anything. You should also have zinc collars on your shaft. Yeah - I get barnacles on my shaft also, I knock the big parts off with something hard like a scraper, and finish with scotch bright or a wire brush. They come off easier if you get them when they are wet, and don't let them dry out.

I've used Petttit Prop-Koat on my propeller with some success, but its very expensive and application is a two step process (primer and clear coat finish). I might be tempted to try it on my shaft but I would be careful to avoid coating where the zincs were going, you want a good electrical contact between the zinc and the shaft.