How to Apply Single Stage Paint

Single-stage paint application is still relatively common in body shops and, in particular, is still widely used on light and heavy commercial vehicles. While two-stage systems use a base color that is subsequently painted over with a clear coat, many single-stage systems use a urethane base that provides a hardened gloss finish in one full application. When used in conjunction with a compatible hardener or accelerator, a single-stage paint system can lead to cheaper operating costs, fast drying times and higher levels of productivity.

Instructions

1

Wash down prepared panels with degreaser and dry thoroughly before wiping over the surfaces with a clean tack cloth. Activate the paint with a compatible hardener and thinner, referring to the technical data sheet supplied with the product to ensure the correct ratio is used. Stir thoroughly and add to the spray gun and tighten the lid to avoid spills.

2

Plug the spray gun into an available airline and set the air pressure at approximately 45 pounds per square inch. Position the spray gun so it is directly pointed at the masking sheets to the side of the panel being painted. Pull back the trigger of the gun to produce a supply of paint. As the paint is sprayed from the gun, the air cap will atomize the material to create a wide painting fan. Position your arm 4 to 6 inches away from the surface of the auto body panel.

3

Move the arm sideways, working from left to right using a speed that allows for a full first coat application without the paint running or sagging. Adjust the arm slightly at the end of each horizontal movement to bring it downward and work back in the opposite direction. Cross over each horizontal application slightly so the paint edges merge into each other. Continue until the panel is completely covered, making sure that all edges have received a full application of color.

4

Allow the first coat to cure for five to 10 minutes. Carry out a check on the adjacent masking paper by pressing down on overspray with a finger. The paint should be tacky before a second coat is added. Apply the second coat in the same way as the first, but reverse your painting direction to promote even coverage. If the first coat was sprayed from the top to the bottom, apply the second coat from the bottom to the top.

5

Allow the second coat to cure for 5 to 10 minutes before carrying out a visual examination of the applied single-stage paint. Most modern high-solid materials will only require a two-coat application but colors with poor opacity, such as reds and yellows, may require a third coat to ensure full coverage. Once the panels are fully painted, wash out the spray gun with cellulose thinners.