What Kind of Thinner Should I Use to Remove Paint From Car?

Perhaps you stained your car's paint job with paint from another source -- or perhaps you want to give your car a makeover with a brand new coat of paint. In either case, you will need to remove some kind of paint from the surface of your car. You may need to use thinner to do this, or other methods.

Paint Types

Cars typically require at least four different kinds of paint: undercoat primer, primer sealer, base-coat paints and clear finishes. Undercoat primers are designed to stick to the metal or plastic on the car body. Primer sealers are designed to grip the primer and the base-coat paint. Base-coat paints give the car body its color; and clear finishes protect the base coat while giving it a brilliant gloss. Primers are generally enamels or polyurethanes. Primer sealers are usually either polyurethane or epoxy. Base coats (sometimes painted as both a mid-coat and a base-coat layer) are either enamels, lacquers or polyesters. Each of these responds to a particular kind of thinner, if thinner is to be used.

Paint Thinners

Enamel thinners will contain either toluene or naptha. Polyurethane paints are frequently thinned using compounds that contain mineral spirits. Mineral spirits also work with epoxy, as does xylene. Lacquer thinners use acetone and sometimes toluene. Mineral spirits or lacquer thinners work well on polyesters. There are enough overlaps in these products that you should first ensure that you've correctly identified what kind of pain you are removing, then consult with the resident expert at the paint supplier to get the thinner you need.

Paint Stains

If all you've done is spilled or splashed paint on your car, and the objective is to remove the local stain, the appropriate thinner might be an option. First try water and a lot of elbow grease. If a coat of dirt or oil from the road is between the stain and the clear finish of the car body, rubbing the dickens out of it can get the stain off. If that doesn't work, resort to thinner in a very small quantity on a rag, and again depend on rubbing more than dissolving. This prevents lifting a large area of the clear finish off the car, and leaves you with only a small touch-up to do.

Paint Jobs -- New

If you are removing the old paint to put a new color on the whole car, the best option is not to use thinner at all. Sandblast the entire body until only metal and the old primer coat is visible. That can be touched up with sanders and emery paper until there is a clean surface upon which your new primer coat can adhere. Using thinner to remove paint can turn into a muddy mess. If sandblasting is out of the question, choose a product called a paint stripper or paint remover instead of a paint thinner.