Covering a large painted area with a consistent paint application is a difficult task. Uneven coverage and roller lines will ruin the smooth finish of a surface. To do a good job requires time and practice.
With a paint sprayer, this becomes significantly easier. Paint sprayers ensure a professional and even finish, especially when assisted by the quick delivery of an air compressor. An air compressor saves both time and money, and reduces waste.
An air compressor and spray gun might seem tricky at first, but if you’ve chosen a good air compressor it’s easy to use. Once you’ve mastered the consistent movements, paint spraying a wall becomes a simple task.
What is an air compressor?
An air compressor is a device that uses power to force air into a storage tank. The air then becomes pressurized. When released, the pressurized air has more force and power.
Air compressors have multiple uses, including in construction and manufacturing, but are often used in non-commercial settings for cleaning and paint application.
An air compressor will rarely be specialized for use in spray painting. However, many basic air compressors can be used for painting.
How to Choose an Air Compressor for Spray Painting
The usual air compressor for spray painting is HVLP. This means ‘high volume, low pressure’. HVLP uses a lower pressure than other, more powerful, air compressors.
This makes it better for painting as the paint is less likely to be wasted from pressurized ‘bounce back’.
The softer pressure means more paint will stick to the walls, reducing waste. Too high a pressure can cause an uneven paint finish.
When choosing an air compressor for spray painting there are three key components:
- Pounds per square inch or PSI
- Cubic feet per minute or CFM
- Tank size
When spraying paint the delivery needs to be regular and consistent. That’s what these three components ensure.
The tank size needs to be large enough for a consistent spray, the PSI high enough for constant delivery of paint, and the CFM higher than that of the spray gun to ensure consistent pressure. Consistency in these areas is vital for a good finish.
The PSI should be around 15-45. Optimal CFM is at least 12. To make sure you make the right choice, check the requirements of your spray paint gun when choosing a compressor.
How to Use a Paint Sprayer with an Air Compressor
- First, apply your safety gear. Goggles, a safety mask, and gloves should be worn at all times when spray painting.
- Clear the area. Remove any nearby items such as furniture. Cover what can’t be removed with a drop cloth or sheeting. Low pressure reduces the amount of excess spray, but it doesn’t eliminate the risk. Always paint in a well ventilated area.
- Prep the wall for painting. Wash and dry, sand if necessary. If you need to prime the surface, that can be done by hand with a roller. Or adapt the steps below to apply the primer with an air compressor and gun.
- Attach the spray paint gun to the hose and check it’s secured. The gun should trigger lock when in place.
- Attach the other end of the hose to the air compressor and check it’s secured. The hose must be tight enough to prevent air leakage. The air compressor and spray gun manual will guide you with any issues.
- Mix your paint and solvent to the correct consistency. Test the paint on a spare surface to check consistency levels.
- Connect the air compressor to the power source, and allow it to build pressure.
- Check the pressure of the air compressor. The PSI should easily adjust to the correct pressure.
- Fill the canister with the paint/solvent mixture. Pour a small amount into the paint cup attached to the spray gun.
- Prepare the gun for use by adjusting the fluid pressure control. Refer to the guns manual for the best setting.
- On a disposable surface, spray your paint, checking for pressure, coverage, and ‘bounce back’. To start, set the pressure to 0 and gradually increase until the paint starts spraying smoothly and consistently. When you’re happy with it, then you can move on to your wall.
- Stand with the gun 5 to 10 inches away from the surface. Practice moving the gun back and forth, so you can get a feel for the weight and the swing. When you’re comfortable with the movement, it’s time to start spraying.
- Press down on the trigger of the gun to spray the paint. When the trigger is pressed, the gun must be moving or you risk causing drips. For an even spray, move the gun in continuous, consistent, straight strokes. Each stroke should overlap the previous by no more than 50 percent, but some overlap is necessary for an even coating.
- Continue until the surface is covered, refilling when necessary.
- Leave to dry for 12-24 hours, then apply a second coat if needed.
When you’ve finished spraying, turn off the air compressor and remove the paint. It’s important to keep the gun clean, or you may face blockages at a later date. For a quick clean, fill the paint cup with thinner, and spray until it comes out clear.
After following these steps, your surface should be covered with a consistent layer of paint. Each spray gun and air compressor is different, so experimenting before you start is important.
Changing the PSI will alter the finish depending on the type of paint you’re using. The weight of the gun is also important, as it will affect your movement and the movement of the spray. Practice moving the paint sprayer around first.
What can I use an air compressor for at home?
Outside of spray painting, an air compressor has many uses. It can be used as a cleaning tool for large areas.
The pressure can remove caked on dust. It can be attached to a multitude of tools to make jobs easier.