One of my first projects, after bringing our '99 Scamp
to it's new home, was to inspect/repaint the frame. Most of the areas looked fairly good and free of rust. Repainted using black Rustolium spray paint
. There were several areas where surface rust was evident. I wire brushed and sprayed these with 95% zinc primer followed by the Rustolium. There were a few fittings on the door of the Scamp
showing rust (and leaving a rust stain down the side of the hull). I removed all the surface rust, masked these and sprayed with the 95% zinc primer. Still looking good after two seasons.
I use the same treatment on some of the steel components on my boat/trailer which is used exclusively in salt water and it holds up very well.