How to Repair a Rusty Car Frame
- 1). Cover a large radius around each rust spot with tape and newspaper. Tape as close to the rust as possible. This will prevent any rust particles or paint from ending up on other areas of the frame.
- 2). Sand away the rust with a metal grinder. Work carefully; if you work too fast you could take out chunks of the car frame. Hold the grinder at a 45-degree angle at all times. Wear safety goggles because sparks will fly while using the grinder.
- 3). Sand the surface by hand with 120 grit sandpaper until the surface is smooth to the touch.
- 4). Apply a coat of rust converter to the surface. This will convert any leftover rust particles into a paintable surface. It also will prevent any rusting in the future. Allow the converter to dry.
- 5). Apply three coats of paint primer. Wait until each coat is tacky before applying the next.
- 6). Apply two coats of oil-based paint to the surface. The car's manufacturer may sell the exact paint needed. Your vehicle's title has the name of the paint color for easy matching.
- 7). Remove the tape and newspaper to expose the frame of the car. Wait 48 hours before washing, waxing or exposing the surface to the elements.
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