The paint gun sprays paint or varnish through the air onto a surface. The most common systems use compressed gas so that the material comes out with the correct pressure.
The best HVLP spray guns are the evolution of the traditional airbrush used to do detailed work. These guns, on the other hand, are used for large surfaces and can be used manually or automatically. They also have interchangeable nozzles for changing the spray pattern.
The origins of the paint gun date back to 1887 and come from the United States. Over the years, they changed the design until, in 1907, Dr. Allen DeVilbiss’s son improved on his father’s invention by creating the first manual paint gun using compressed air. The company founded by Dr. Allen DeVilbiss still exists today and is, in fact, the world leader in conventional spray guns.
What kind of spray paint guns are on the market?
Gravity spray guns: these are characterized by a tank on top where the paint is located. By placing the deposit, there will be a better flow of paint due to the effect of gravity. They are used for a fine finish or for lacquers. They are usually covered with Teflon to prevent the paint from sticking to the body. Professional guns usually have an aluminum body to make cleaning easier.
Gravity guns (HVLP: High Volume, Low Pressure): They differ in the machining of interior parts. The aim of these is to achieve a better performance, achieving a reduction of up to 75% in paint loss by dispersion.
Suction guns: they incorporate a tank in the lower part of the gun, so instead of acting by gravity, they work by suction absorbing the paint thanks to the venturi effect.
Trans-Tech or hybrid, with a pressure increase, compared to HVLP but maintaining the economic advantages of paint saving.
Parts and maintenance of a paint spray gun
The most important part of a gun is the airhead, where air and paint are mixed. Depending on the design and size of this part, paint consumption and paint quality will vary. The head is the piece that determines the price difference between a good and a lower quality gun.
The heads of an HVLP gun have a larger outlet hole than the Trans-Tech equivalent, so at the same pressure, a greater volume of liquid will come out, although it is not equal to the pressure of the Trans-Tech guns.
Another key part of the gun is the assembly formed by the nozzle and needle, which acts as a valve for the passage and dosage of the paint. These paint guns will require a heavy-duty repair shop air compressor to be efficient.
At the rear, we will find the paint regulator. The tighter it is, the less paint will come out. There is also another one that allows you to vary the shape of the paint jet.
As far as automotive paint maintenance and cleaning are concerned, we must be meticulous and dismantle and lubricate the parts of the gun one by one. When we do correct maintenance, a gun can last us a lifetime. On the other hand, if one day we forget to clean, for example, the varnish, it is easy that it no longer paints correctly.