Before a painter can develop a paint plan for a plastic part, he or she must identify what type of plastic was used to make that part. Though we use the general term "plastic" to identify many different non-metal parts, there is a staggering array of plastics used in manufacturing a vehicle. The two main categories of plastics used are Thermoplastic, a type of plastic that will soften when heated, and Thermoset, which after it hardens or cures, will not soften when heated. Many flexible parts on a vehicle such as front and rear fascia are made of a Thermoplastic material that when heated will become even more flexible. In contrast, mirrors and grilles are made with a Thermoset plastic.

Parts also can be made from many different compounds such as Thermoplastic Olefin (TPO), Polyurethane (TPUR), Acrylonitrilebutadiene-Styrene (ABS), Sheet Moldable Compound (SMC) or Fiber Reinforced Plastic (FRP), just to name a few. Plastic parts have a plastic identification ISO code molded into the back that identify the type of plastic from which the part was made. Parts that are made from Olefin Polymers must have an adhesion promoter used before refinishing to assure that the finish will not delaminate later.

New Unprimed Parts

Painting new unprimed plastic first requires a thorough cleaning of the part: soap and water washing, removing mold release agents, chemical cleaning and inspection are all parts of the pre-sanding cleaning. The part must be sanded and cleaned, then anti-static and/or adhesion promoter is applied. The part is then sealed, color coated and clearcoated.

A staggering array of plastics are used in today's vehicles.