If you are looking for the best spray gun for a small compressor then there are several things you should should keep in mind to get the best performance.
Air Compressor Capacity
The first thing to consider is the amount of air your small air compressor can pump and the amount of air the spray gun uses.
This air compressor specification you will need to know will be called the CFM (cubic feet per minute).
This CFM value is a measure of the volume of air the compressor can pump and the spray gun needs to operate properly.
One thing to keep in mind is that an air compressor’s CFM rating will vary depending on the conditions it operates in.
You will sometimes see air compressor capacity given in SCFM instead of just CFM.
The S in SCFM stands for standard.
This just means that the CFM rating is given under a standard set of conditions, so that different air compressor specifications can be compared directly without variables such as temperature, atmospheric pressure, etc affecting the rating.
Bottom line is that you can’t have too much compressor CFM.
If the CFM of your compressor is higher than the spray gun requirements that is fine, but if it is lower then you will have issues.
Spray Gun Air Consumption
Any air tools, including spray guns, should have the required amount of air to operate the tool specified.
This required amount of air will also be specified in CFM, so that does make it pretty easy to compare with your compressor capacity.
If you need to operate the spray gun for extended periods then you compressor will need to have a higher CFM value than the spray gun you plan to use.
In general, it is a good idea to have a compressor with a CFM rating higher than the spray gun to give some margin of safety due to differences in conditions, tools ratings, etc.
The amount of margin needed varies depending on who you ask, but a good rule of thumb is for your compressor to have a CFM rating at least 20% – 50% higher than your spray gun.
What if the Spray Gun’s Air Needs are Too High?
If the CFM value of the spray gun is too high than your air compressor can not supply the amount of air needed to operate the spray gun continuously.
In this case, using the spray gun will deplete the air compressor’s storage tank faster than the compressor can fill it.
This will cause the compressor’s pressure to eventually drop below the required pressure for the spray gun to operate properly.
Once this happens you will have to stop using the spray gun and wait for the compressor to catch up and fill its air storage tank.
If you only need to use your spray gun for a short amount of time before stopping then the compressor’s air storage tank may have the capacity to offset its lower CFM pumping capacity.
CFM and Working Pressure
This is where figuring out the spray gun your compressor will support can get a little tricky.
Another thing to keep in mind is the working pressure of the spray gun.
When you see a CFM rating it will be that rating at a certain pressure (PSI).
The most common pressure to see on air compressor ratings is 90 psi, but sometimes you will also see CFM ratings given at additional (usually lower) PSI pressure values.
The main thing to keep in mind is that an air compressor will be able to provide a higher CFM at lower pressures.
HVLP Spray Guns
If you have a small compressor then you will likely be looking for an HVLP spray gun.
HVLP stands for High Volume Low Pressure, which is basically just what is sounds like.
These spray guns deliver a high volume of paint using a lower amount of pressure (PSI) than standard spray guns.
Recommended Spray Guns
Here are some spray guns we found while researching the best spray gun for small compressors.
DEWALT HVLP Spray Gun (DWMT70777)
- HVLP Design
- Graviy Fed
- 600cc Paint Cup
- 3.5 CFM at 30 psi
Check DEWALT HVLP Spray Gun Prices
Graco-Sharpe FX3000 Spray Gun
- HVLP Design
- Graviy Fed
- 600cc Paint Cup
- Includes Wrench and Cleaning Brush
- 9.5 CFM at 40 psi
Check Graco-Sharpe Spray Gun Prices
TCP 9 Piece Spray Gun Kit
- HVLP Design
- Graviy Fed
- 2 Full Size Guns, 1 Detail Gun
- 2 One Liter Cups, 1 150cc Cup
- Includes Wrenchs
- Includes Cleaning Brushes
- Includes Pressure Regulator and Filter
- 3.5-7.1 CFM at 29-50 PSI
Check TCP 9 Piece Spray Gun Kit Prices
Conclusion
As you can see, there are many variables to take into account when picking the best spray gun for a small compressor.
Keeping these considerations in mind when picking a spray gun will help ensure you are able to accomplish the jobs you need to do.
If you are in doubt about your compressor and/or the spray gun you are thinking about buying the it would be best to contact the manufacturer.
They should be able to provide you with advice.
