A good spray pattern indicates that the paint or coating is completely atomized and distributed evenly on the surface. Several techniques help determine the quality of the spray pattern and the quality of the finish.
- Adjusting the pressure
- Aiming of the spray pattern
- Movement of the spray gun
The following techniques ensure a long-lasting quality finish
Adjusting the pressure for spraying
It is best to spray at the lowest pressure that completely atomizes the coating. The pressure control should be set at a low-pressure setting and slowly increased until the paint is completely atomized. If the spray pattern has fingers or tails, then the pressure should be increased.
The spray gun should be held approximately 12 inches (30.5 cm) from the surface, and aimed straight (both horizontally and vertically) at the surface.
Extremely large tips will require you to move further away to achieve a good spray pattern.
The spray gun should move across the surface with the wrist flexed to keep the gun pointed straight at the surface. “Fanning” the gun to direct the spray at an angle will cause an uneven finish.
The spray gun should be triggered after beginning the stroke (also called the lead stroke) and released before ending the stroke (also called the lag stroke).
The gun should move during both the trigger squeeze and trigger release. This technique prevents blotches of thick coating at the beginning and end of each stroke.
This technique ensures that an even amount of coating has been sprayed onto the surface. The spray gun should be aimed so that the tip points at the edge of the previous stroke, overlapping each stroke by 50%. To maximize efficiency when spraying on broad, open surfaces, like ceilings and bare walls, the outside edges of walls should be sprayed first. The middle can then be sprayed quickly, requiring less precise strokes.