Instruction to set up HVLP spray guns – Part 2

Part 1

Third step: set up

Not be the same as previous model, to operate smoothly, HVLP gun needs to reset up each time using. The outside condition like humidity, temperature, weather can affect the way to set up gun that day. Learning how to set it up help you implement wholly by yourself.

The testing at first to check whether the recent condition of the gun is suitable or not is necessary. You need a small piece of masking paper for spray test before setting up.

First, set the pressure at the gun inlet by using air regulator through the gauge which attach to the gun. Set at about 50psi to get the trigger pulled. When setting reaches 50psi, maximum psi may be in the gun, but it is existed under low side instead of high, so it is still safe. The most popular range of air regulator is from 40 psi to 60 psi. Next, close the air volume control knob that near the entrance air hose. After that, open the trigger pulled till the point that air volume remains stable. The easiest way to realize that point is to listen to it.

When the gun is well-prepared, air pressure and volume is set next.

For example, you are going to spray a fan about 6 inches tall. First, you must find out the fan control knob, it is the top one or on the side. Open it all the way and then turn it down slightly. To paint a 6’’ fan, you had better use a 6’’ gun from the surface. Next, material knob, the second one down, will be screwed until it seats, and then unscrewed about 2 1/2 turns.

Tests can start immediately. Hold the gun at exactly 6 inches, pull the trigger for only a second and close it. A cigar shaped pattern is what you get now on the masking paper. Adjust the position of the fan until it reaches 6’’ tall and 6’’ far from the paper. Until now, no adjustment on fan control is allowed. In case that control is changed, the psi at the cap is also changed, so all the preparation should be carried out once again.

Next, keep the gun far from the paper at about 8 or 9 inches, it is the suitable distance to spray. Assure to keep the gun not too far or too near the paper to avoiding losing pattern. Now test it for the second time. The cigar shaped pattern appears again but in different size and color. The pattern now has the full coverage in center and fading in outer parts. Outside is fade because you use to ‘tune’ the gun.

Here below are some example of cigar shaped pattern with according quality to help you know your setting is good or not.

Not always having the good results, some problems still remain such as too much airflow, not enough air flow, not enough material or too much material.

In case the material is abundant at both end, but lack in the middle, your gun may contain too much air flow. And when material only situates in the middle, only little air flow is in the gun.

The good position of the gun may lead to a fully covered center. If you keep too far, the center is fade or uncovered. On the contrast, if you keep so close, there will be a flow of abundant paint from the center. For this problem, you just change the position of the trigger to fix it.

However, if too much material is applied, you ought to screw slightly the material knob or turn down the air pressure on the regular a little bit.

A perfect jog with none droplets and losing full coverage is what we aim to. To get this result, the material control knob should be turn in a little at a time or raising the air pressure.

All noted here are some tips that allow you know more about the character and also the usage of HVLP spray gun. Hope that with that information, you can set up HVLP by yourself and complete a perfectly painting job.