PAINT TIPS AND TRICKS FROM A PRO

Show-quality paint from prep to the spray gun

By Angelo Van Bogart

We followed the Mustang fastback featured elsewhere in this issue to Townsend Auto Body in Waupaca, Wis., where it was sprayed a metallic maroon base coat/clear coat, and we picked up some paint tips and tricks from pro Mark Townsend. Townsend’s shop boasts a modern spray booth for professional-quality paint jobs, and the pointers he shared revolved around the equipment and products he used in the Mustang project. Even if you don’t have all the professional equipment of a full-time body shop, there are plenty of things to learn from this master of his craft, so let’s dig in.

Pre-paint prep

When the Mustang arrived at Townsend Auto Body, the metal work had been completed, which included replacing and fitting metal all the way to the final pre-paint finishing. As it arrived, the Mustang’s floors had already been painted and only the outer body, which was about to receive color, needed final sanding before paint.

Final sanding before paint should be completed in angled strokes,
not vertical or horizontal strokes.

The body’s three coats of primer had been block sanded with 320-grit paper using a board file. Each time he sanded, Townsend shifted the direction of his passes with the sand paper, but always kept the direction at an angle — there were no completely vertical or horizontal movements with the sandpaper. This and the following steps removed any orange peel in the primer.

Townsend then moved to a finer-grit 400 sandpaper. He hand-sanded edges and concave areas carefully with sandpaper on a rubber or foam block that flexed with the car body’s contours, then used a 400-grit sanding disc attached to a dual-action sander for the larger, flat surfaces. For the third sanding, Townsend finally moved down to 600-grit and wet-sanded the body.

Flexible sanding blocks are used at edges and in areas with character, such as the concave depressions on the side of a Mustang.

A dual-action sander (DA) can be used on larger, flat areas.

Compressed air was then blown across the body to release loose sanding dust. Areas along the edge of the tape and cracks in the body were given particular care to remove dust that could be disturbed and land in the paint while it’s being sprayed. Since the Mustang was delivered to the paint shop on a rotisserie and would be painted on the same rotisserie, it was also sprayed with compressed air.

Then the body was then wiped down with wax and grease remover to pick up any other loose material, leaving a smooth canvas upon which Townsend could spray the color. To further prevent dust from landing on the body, it was also wiped with an anti-static wipe that prevents dust and lint from the paint suit and in the air from being attracted to the paint.

All areas that would not receive paint should be carefully taped to prevent over spray from coating areas where color is not intended. Also, when using compressed air to blow dust from the surface to be painted, be sure to give special attention to the dust trapped in taped areas.

Paint booth prep

Before moving the Mustang into the paint booth, Townsend used compressed air to blow out dust from inside the spray booth (including the walls), swept the floor and wet it to weigh down any residual dust. Filters in the air exhaust system were checked and any filters in poor condition were replaced. Any burnt-out bulbs were also replaced for maximum visibility.

Map a route and spray

Before picking up a spray gun, Townsend recommends painters choose a path that works best with their air flow. He works from the back of his spray booth to the front, starting at the farthest point from the exhaust of the booth’s ventilation system. This pulls the paint from the gun, across the body and to unpainted areas, then out of the booth. Spraying the opposite direction would leave overspray on freshly painted areas and result in “dry-looking” or mottled sections in the paint.

Townsend would be spraying the Mustang in a transparent metallic base coat, so he applied a tinted sealer over the primer first. The closer in color the sealer being sprayed is to the base, the less material is required to cover the body.

Between spraying the base coat and primer, a tinted sealer was sprayed on the body. It appears pink here.

Jams and inner areas are painted before the outer body panels.

The proper painting equipment should include a full suit and respirator and gloves. Also notice the floor has been wet down to keep dust from floating in the booth during the paint process.

After following the manufacturer’s guidelines for letting the sealer cure, Townsend began spraying the base coat. The car was given three good coats of the base color and fourth lighter coat in quick succession to make sure the application was even. The fourth lighter spray is particularly important when spraying metallic colors to ensure an even look. During the painting process, Townsend would spray, mix another batch of paint, then spray it and repeat until the car was covered.

The base coat has a dull appearance before it is covered with clear.

After the last basecoat has set for the recommended time, Townsend then applied three coats of high-quality overall clear coat, being sure to allow enough time between coats to avoid any runs in the finish. All told, it took slightly more than four hours to paint the car.

With the clear on the base coat, the paint will finally have the expected shine of a fresh paint job.

Spraying clear generates a particularly large amount of fog in the spray booth and requires close attention while spraying to ensure full coverage. While spraying each coat, the painter started at the farthest point from the exhaust and worked toward it so the paint materials were not pulled over freshly painted areas.

After the clear has been allowed to cure, it can be buffed and reassembly of the car can begin.

When spraying the paint, it’s important to keep nearby areas wet for a consistent coating. Townsend recommends keeping the time between painting adjacent panels to a minimum, thereby reducing the dry time while overlapping. Any professional will also warn against painting part of a panel, moving to another area of the car, then returning to that panel with too much time passing in between.

“Always look at what you spray,” Townsend said. “If it’s too light, go back over it while it’s still wet. If you leave a spot, you’ll get dry spots when covering it up.”

The time between spraying the color and the final clear coat varies based on the manufacturer. If not enough time is given to let the color cure, the color will loosen beneath the clear. When painting a complete car with clear, Townsend also recommends a slower-drying clear. In this project, the clear was given at least 48 hours to dry before it was buffed to the perfect shine.

SOURCE:
Townsend Auto Body
801 Redfield St., Waupaca, WI 54981
715-258-7941