We all know that a spray gun is not a single part that can be used directly, it must be connected to an air compressor and a paint tank/barrel. A proper understanding of the connectors on the gun will be of great benefit to us in selecting air hoses and purchasing replacement parts.
Typically, the spray gun has two connections, the air inlet, and the material inlet nipples.
Air Inlet Nipple
Most are made of stainless steel, located on the bottom of the spray gun, connect to the air compressor hose. The regular size is G1/4” air inlet, also have a quick air connector, which is more convenient, but it might cause a drop in air pressure and wear out easily with long term use.
Fluid Nipple
The fluid nipple is also made of stainless steel, but it is located in 3 places for 2 feed-type spray guns. As for the gravity spray gun, you will find it in the spray gun head side or center, for pressure one, positioned directly below the head. This is beneficial for connecting paint cups or diaphragm pumps.
The fluid inlet size is determined by which spray gun you use, how much paint volume will pass through the material passage. So we have 2 options for fluid inlet connect on the spray gun.
- G1/4” for compact size spray guns, like Wolter W-101, W-71, R2-R/F
- G3/8” for full-size spray guns. like Wolter W-77
The last point is most important. Each country has its standards for connectors, it depends on the pipe size, so be sure to check with the factory before purchasing the spray gun to avoid mistakes.
For American Standard Pipe Size(NPT) details, you can find in Wikipedia
For British Standard Pipe(BSP), you can see more in Wikipedia