There is no panacea one coat primer/paint. The way to protect it properly is to epoxy prime, then base coat (black or gray or whatever), then clearcoat with a flattening agent. The primer is not water or UV resistant and the base coat is UV resistant but not water resistant and will not stick to bare metal. The clear is water/uv resistant.


Paint & Body Shop moderator
A lone amateur built the Ark. A large group of professionals built the Titanic.