I have a boat trailer with heavy rusting and pitting.
I believe that it was (once upon a time) a mostly a galvanized main frame with a second non-galvanized steel frame attached. I will be replacing one of the frame members with a galvanized RHS steel section, which will need to have some parts welded to it. The rest will be wire brushed/sanded and I plan to use RustBlock Fish Oil in the sealed channels.
My question is: ‘What do you recommend for rust prevention for the trailer?’ I was thinking RustBlock Cold Gal (as a zinc primer) with an Rustblock Epoxy Gloss Enamel, but the frame would have to be totally free of rust. (Which means costly sandblasting.) Would it need to be etched first or could you use an epoxy topcoat with less prep?
The painting system you are suggesting on the replacement section is spot on. As for the repainting of the entire trailer, seeing that the trailer is regularly submersed in water, l would recommend the following to provide the best protection to the metal and longer life for the coating:
Remove all rust and wash the surface to remove any contamination from the metal. If sand blasting, clean the surface to remove all sand residue. Apply RustBlock Cold Gal to the metal, allow to completely dry and apply two coats of RustBlock Epoxy Gloss Enamel.
To prolong the life of the coating, wash the surface on a regular basis and rinse with fresh water.
All answers have been provided by our RustBlock paint specialist