How to Fix a Car Scratch
An angry ex keys your car, an ignorant shopper lets a shopping cart ram into your car, an unthinking person gets out of their car without really assessing how much space they have to do so. No matter how it happened, you now have an unsightly scratch in your car. But don't worry, there's always a few things to try before paying a few hundred dollars at a professional body shop.
Firstly, not all scratches are, indeed, scratches. If the object hitting your car is softer than the paint, it will instead deposit a material onto the surface. This can be removed by simply rubbing it away, or for more stubborn marks, use an adhesive remover, and for the most stubborn of marks, use acetone or a lacquer thinner on a soft cloth.
That didn't work? Well, now we will work on getting that scratch out. Well, not so much getting it out as we're going to sand the paint away from the surrounding areas so that it's at about the same level as the scratch.
You'll need shoe polish or white out (something of a contrasting color to your car), ultra fine 2000-3000 wet/dry sandpaper with a rubber or wooden sanding block, a bowl of cold water (with a tiny bit of liquid dish soap),
Rub a material of a contrasting color into the scratch. (Shoe polish works wonderfully for lighter colored cars, white out or a white shoe polish for darker colored cars.) Once the scratch is filled in with the material, wipe the excess away.
For the next step, you'll need an ultra fine 2000 to 3000 grit wet/dry sandpaper, which you will be able to find at most auto supply stores where body supplies are sold. You will need to put the sandpaper onto a rubber or wooden sanding block and dip it into cold water.
Slowly and lightly begin to sand the scratch, using sixty degree strokes. Move along the length of the scratch, being sure to dip your sandpaper into the water frequently. Keep working until you see the scratch begin to disappear.
If needed, spray the area with a clear coat. You can also find this at most auto shops that sell body supplies. Use a rubbing compound and a soft cloth, and buff the area. Rinse the area off.
It's also a good idea to use a good car wax after you are finished.