There are two types of spray systems: air and airless. An air gun mixes siphoned paint material with compressed air and sprays the mixture form a nozzle. An airless gun, on the other hand, uses a pneumatic pump to force paint through the nozzle under high pressure. An airless gun delivers much more material that an air gun and is used for large projects where a fine finish is not required. Large airless guns are the shotguns of the painting world.
- Air sprayer
- Air compressor
- Canister-style airless sprayer
Air Sprayer Operation
Unscrew the paint cup and fill it about 3/4-full with paint. Thin this with about 10 percent solvent. Screw the cup back on and connect the air line from the compressor. Turn the compressor on.
Test the spray on a scrap piece of wood. Adjust the air pressure and the nozzle until you get a fan about 12 inches wide from a distance of about 6 inches. Turn the nozzle to change the orientation of the fan from horizontal to vertical.
Spray in long, even strokes, keeping the gun about 6 inches from the surface and overlapping about half the width of the fan. The goal is to leave a shiny coat of material that doesn’t drip, sag or separate. When you are done, add another coat moving perpendicular to the direction you just sprayed.
Disconnect the air, remove the cup and empty it when you are finished. Clean the cup thoroughly with solvent and remove the tip and immerse it in solvent. Leave it there for a while before wiping it clean with a rag.
Airless Sprayer Operation
Unscrew the cup and fill it with paint. Screw the cup back on, plug in the sprayer and test the spray pattern. If it is chunky or too thin, add solvent to the paint. Adjust the nozzle so that the pattern is about 2 feet wide from a distance of about a foot.
Keeping the gun a foot or more from the surface, spray in even strokes, overlapping about half the width of the spray pattern. Don’t linger, as the paint will build up quickly, causing sags and runs.
When you have applied the first coat, add a crosshatch coat in the perpendicular direction. The goal is the same as with an air sprayer: to leave a shiny surface of paint without drips or separation.
Empty the cup when you are finished and clean it. Remove the tip, immerse it in solvent and clean it well with a rag.