I've noticed a 3/8" rust spot in my old bathtub. Is there anything similar to the automobile rustkits that would allow me to fill in the spot with some sort of quick drying epoxy or caulk, smooth it over, with a clearcoat like paint?
I live in an old building and the bathroom sink had a larger rustspot. When I poked my pinky in it, it went right through and I don't think the sink is salvageable.