A deep car key scratch does not necessarily mean an expensive new paint job. Cars have a thick layer of paint, which means removing the top layers does not diminish its appearance. Removing the scratch successfully involves using certain products and procedures to ensure no other damage is done to the car's paint.
Clean the scratched area with a soapy sponge. Mix 1 tsp liquid dish soap into a bucket of warm water. Wash dirt and dust from the area. Rinse with cool water and wipe dry with a soft cloth.
Put 1/2 tsp black shoe polish onto a rag. Rub the polish into the scratch mark. Use black polish for light-coloured cars and white polish for dark colours. Remove any excess polish from around the scratch area with the rag.
Moisten a wet/dry 2,000- to 3000-grit ultra-fine sandpaper with cool water. Squeeze a drop of liquid dish soap onto the sandpaper.
Sand the scratches slowly using gentle pressure. Rub the sandpaper back and forth, wetting it after five or six strokes. Continue rubbing the scratch until you no longer see the shoe polish.
Place 1 tsp rubbing compound on a soft cloth. Rub the compound into the affected area using circular motions. Remove the cloudy compound from the paint with a clean cloth, buffing it to a clean shine.
Use car polish and wax to add a protective coat to the car's paint.