Lexan plastic is a very hard and virtually unbreakable type of plastic polymer used in the production of a variety of items including astronaut helmets, motorcycle and safety helmets, and airplane and other vehicle parts. Lexan accepts most acrylic paints well and cleanup is simple. Airbrushing is the most efficient and fastest way to paint Lexan plastic quickly and evenly. Applying acrylic paint to Lexan helps protect the surface from both ultraviolet light and water corrosion.
Clean the plastic thoroughly before painting. Use a bucket and mix a gallon of warm water with a tablespoon of liquid dish soap. Use a soft sponge to gently wipe the surface of the plastic thoroughly. Allow it to air dry, or dry it with a soft, lint-free cloth to avoid leaving behind fuzz or fibers.
Mask off any areas that you don't want painted. Cover any parts of the plastic that stay unpainted with newspaper and masking tape. Smooth the tape down evenly with your fingers, laying the edge of the tape flush with no ripples where paint could seep in.
Lay plastic sheeting over the floor or table to avoid getting a random spray of paint onto the surrounding area. Place the Lexan plastic on small wood blocks to raise it up and prevent it from sticking to the sheeting as it dries.
Spray coatings of paint onto the plastic. Use an airbrush on a fine setting to apply an even first coat. Hold the airbrush 4 to 6 inches from the plastic and move it slowly from side to side until you cover the entire surface. Allow the paint to dry thoroughly for at least two hours.
Apply a second coat of the paint with the airbrush using the same side-to-side motion as before. Leave the paint to dry again for another two hours. Examine the paint to verify the quality of the paint job. If necessary, add more coats until the coverage is to your liking.
Remove the masking tape or newspaper from the Lexan and dispose of it properly. Throw away the plastic sheeting, and remove any paint spills or splatter around the area using denatured alcohol or mineral spirits and a clean rag.