Why do I get streaks or bands in my spray pattern

Why do I get streaks or bands in my spray pattern?

Answer: Streaks in the spray pattern, especially heavy bands at the outside edge, indicates low pressure at the tip. In order to correct the issue, turn up the pressure control knob until these bands are eliminated. If the sprayer is already at maximum, you may have to use a larger diameter hose or shorten the length of the hose to reduce the pressure drop. Also make sure that all paint filters in the system are clean.

Airless Paint Sprayers are rated for a maximum tip size. Using a tip that is larger than the maximum size or a tip that is worn larger will cause low pressure. The tip should also be the proper size for the type of material being sprayed. After extended use, spray tips will wear out, causing a poor spray pattern. You may have to replace the spray tip with a new one or less size to restore the proper spray pattern.

for our DP airless paint sprayers, we have 2 types pressure regulators

A. Mechanical pressure regulator

for this system, the pressure is controlled by the micro switch inside the regulating system.  This system could cause more pressure drop such as 30-40bar (for example from 150 – 190bar), it will get unsmooth finishing and looks not so professional.

so the painter has to spray slowly when the pressure get down. otherwise the final coating is not equal between the high pressure and low pressure.

we have another recommendation, chose a bigger tip size, to make sure the pressure gap is smaller. but this will make the motor on heavier duty job and it will short the lifetime of the motor.

B. Electronic pressure regulator

for this electronic system, the pressure is much more stable than above system.

we always recommend our clients to buy this electronic pressure regulator, because the pressure is only 10-20bar difference.

the final finish coating is very nice and smooth / equal. this will make sure the spraying finish is perfect

if you are small contractors or semi-pro painter, you can take the A. Mechanical system

if you’re professional builder / contractor / painter, electronic pressure regulator airless sprayer will be you 1st choice.

Why my paint sprayer leaving lines during spraying?

It’s because of the low pressure during the spraying job.

if the spraying pressure is high enough to atomize the paint, you will see 2 lines at the edge of the spraying pattern. 

so when you see your paint sprayer leaving lines, then you must find a way to increase the spraying pressure. 

1. adjust the pressure regulator to higher or maximum to see if the lines disappeared.
2. if the problem still appeared, then you need to change to a smaller spray tip size. for example, you’re now using a tip size 517 (0.017 inch), then you need to change to 415 or 515 (0.015 inch).  if you’re using 533 tip size (0.033 inch), then you need to change to 531 0.031 inch or 0.029 inch.