Cars are prone to rust because of the metal used to make them. Whether the rust is on the frame of the car or on the door, rust is the result of metal combining with water or moisture. Although cars are now coated with materials to protect them from rust, as time passes the coating wears off. Also, damage to the car, such as dents or scratches, exposes the underlying metal to the elements. Removing rust from the car is necessary because if left untreated the rust will spread.
Scrape off the rust. Use a wire brush or steel wool to scrape the rust stains off the car. Another solution is to first apply mineral oil, WD-40 or other lubricant to the rust stains. Apply mineral oil with a paper towel. If using WD-40, spray it on the stains. Wait several minutes. Then scrub away the rust stains. Use elbow grease for tough rust stains. Wipe clean. Hardware stores sell WD-40 and mineral oil.
Make a lemon and borax paste. Mix 1 part lemon juice with 2 parts borax. Allow the paste to thicken. Then apply it to the rust stains with a scrubbing pad or steel wool. Wait 10 to 20 minutes for the rust to absorb the paste. Then use a scrubbing pad or steel wool to scrub at the rust. Wipe clean.
Apply rust removers. Buy a rust remover form a hardware store or home-improvement centre. Put on rubber gloves and a face mask. Apply the rust remover to the stains with a scrubbing pad or steel wool. Allow the rust remover to soak into the rust. Wait several minutes, then scrub at the rust stains with the steel wool. Wipe area clean. Rust removers contain acids that dissolve the rust and are very effective for cleaning off large areas of rust or rust that can’t be removed by other techniques.