Rust-Mort, manufactured by SEM Products, transforms rust into a protective coating on automobiles and other metal surfaces around the home before they are repainted. This product is potentially dangerous when inhaled or if it comes into contact with your skin. Use it only in well-ventilated areas. Before applying Rust-Mort, which contains acid, review the material safety data sheet from the company for an overview of safe handling.
Rub the rusted area with a wire brush to remove loose rust. Do not try to remove all the rust; some rust is necessary for the product to work effectively.
Wear protective gloves and a face mask. This product contains phosphoric acid, which is caustic.
Dip a clean, wide paintbrush into the Rust-Mort and allow excess to drain back into the can.
Apply a thin coat of the product on rusted areas, distributing it evenly. Repeat the application to add three or four thin coats, rather than one thick coat.
Allow the surface to dry for at least 24 hours.
Dampen a cloth and wipe the surface to remove any residue. Allow the surface to completely dry before applying primer or paint.