Rust on a car is like cancer. It will spread and eventually cause structural damage that cannot be repaired. Even a small amount of rust can spread under the paint, revealing nothing until the paint starts to bubble up with rust. A severely damaged, rusted car panel must be replaced. For smaller amounts of rust, the panels can be repaired to look like new again.
Instructions
1. Use a grinder on the rusted area to remove the paint. Once the paint is removed down to the bare metal, you can see how much damage is present. Use the grinder to remove all surface rust on the car panel.
2. Make sure the panel is structurally sound by pressing on it everywhere rust was present. If it gives, the rust has completely damaged the panel and it must be replaced. If the rust has created holes larger than the size of a nickel, the panel should be replaced. If the rust was just on the surface or created pitted areas, once it is grinded away the panel can be repaired.
3. Apply a thin coat of auto body filler over the areas that had rust or pitted areas. Make sure the filler fills in and covers all uneven or rough areas. Allow an hour for the filler to completely dry.
4. Sand the filler smooth and level with the surface of the car by using 120-grit sandpaper and a dual action sander or block sander. The dual action sander requires an air compressor and air hose, but makes sanding much easier.
5. Spray two thin coats of primer over the repaired area. Allow each coat 10 minutes to dry. Wait one hour after application of the second coat before sanding. Sand the primer lightly using 300-grit sandpaper.
6. Wipe the area down with wax and grease remover and a microfiber cloth. This removes any dust particles and oil from fingerprints that may cause imperfections in the paint.
7. Apply three to five thin coats of automotive paint, allowing each coat 10 minutes to dry before applying the next. Use steady, even strokes, holding the paint applicator about 10 inches from the surface. Wait a few hours for the paint to dry and then apply three or four coats of clear coat paint, using the same methods you did with the paint. Allow the panel to dry for a full day.
