Yes they do work. I use rustmort and there are plenty of products to choose from. The acid is mild and turns the rust dark black if it heavy and grey if the rust is light. Do not sand ove the treated metal, paint it and don't sand through the paint to the sheet metal. The idea is to reapply a seal/etch to the outside of the metal to keep it from rusting again. Use eye protection and hand protection. This is acid/corrosive and will etch the floor if it drips on it so have a rag handy. I apply it with a small paint brush and throw the brush away after its used. I put a small amount of the product in a glass container to work from.