When your airless sprayer doesn’t spray evenly, the result can be frustrating: overloaded areas, lack of coverage or a grainy appearance. There are several possible causes of this problem. In this article, we take a look at the most common reasons and the solutions for achieving an even spray pattern.

Stripes on the side of the airless jet

Stripes on the side of the airless jet

1. The nozzle is worn or unsuitable

The nozzle is the key component in airless spraying. With wear, the orifice widens and changes the spray pattern: it becomes irregular, has streaks or consumes more paint.

Buy a new airless nozzle at Airless Discounter Our article on worn nozzles

 

 

2. Spray pressure incorrectly set

Too low a pressure results in coarse droplets and a lack of uniformity, while too high a pressure causes paint mist and premature wear of the equipment.

  • Symptoms: granular appearance, excessive fog, excess thickness.

  • Solutions :

    • Adjust the pressure gradually until you get a fine, even spray. (Are you at full blast? No chance; dilute the paint to help the machine or get a more powerful machine)

    • Refer to the product manufacturer‘s recommendations.

Purchase a low-pressure nozzle from Airless Discounter Our article on how to regulate pressure

 

 

3. Dirty filtration

Clogged filters (in the handle, gun or pump) restrict the flow and disrupt the evenness of the spray.

  • Symptoms: pulsating jet, reduced flow, irregular projection.

  • Solutions :

    • Clean or replace filters regularly (pump, handle, strainer).

    • Adapt the fineness of the filter to the paint used (finer filters for varnishes/lacquers, coarser filters for interior and thicker paints).

Buy a new filter on Airless Discounter Our article on Graco guns

Here is our table of recommended filter sizes according to the nozzles used:

(On smartphone – continuation of the table —>)

Bore (in inches) Bore (in mm) Recommended spray gun filters
0,007 0,18 #180 (W) – #200 (G)
0,008 0,20 #180 (W) – #200 (G)
0,009 0,23 #180 (W) – #200 (G)
0,010 0,25 #180 (W) – #200 (G)
0,011 0,28 #180 (W) – #200 (G)
0,012 0,30 #180 (W) – #200 (G)
0,013 0,33 #100 (W) – (G) OR #180 (W) – #200 (G)
0,014 0,36 #100 (W) – (G)
0,015 0,38 #100 (W) – (G)
0,016 0,40 #50 (W) – #60 (G) OR #100 (W) – (G)
0,017 0,43 #50 (W) – #60 (G)
0,019 0,48 #50 (W) – #60 (G)
0,021 0,53 #50 (W) – #60 (G)
0,023 0,58 #50 (W) – #60 (G)
0,025 0,64 #50 (W) – #60 (G)
Above #30 (W) – #30 (G) OR without filter (heavy-duty spray guns)

Replace filters

4. Poorly prepared paint

A product that is too thick, badly mixed or contains lumps can clog the filters or the nozzle.

  • Symptoms: jerky flow, frequent clogging, irregular appearance.

  • Solutions :

    • Mix the paint well before use.
    • Do not mix too quickly to avoid adding air bubbles.
    • Filter the product before pouring into the machine.
    • Dilute slightly if necessary, following the manufacturer’s instructions.
    • Use a more powerful machine.
Buy an airless machine that lasts on Airless Discounter Our article on the viscosity of paint

Paint mixing pot - AI

5. Air intakes in the suction system

If air gets into the suction hose or the seals, the pump will no longer feed continuously, which will disrupt spraying.

  • Symptoms: pulsating jet, bubbles in the hose, irregular flow.

  • Solutions :

    • Check the seals and suction pipe for leaks.

    • Check the strainer and replace if cracked or worn.

Purchase an airless connector from Airless Discounter Our article on pressure losses

 

 

6. Damaged hose or gun

Cracks, internal wear or obstructions in the hose can reduce the flow and create an irregular spray pattern.

  • Symptoms: loss of pressure, uneven spray pattern.

  • Solutions :

    • Inspect the hose and gun regularly.

    • Replace if worn or damaged.

Buy a new hose on Airless Discounter Our article on How to Pick the Right Airless Paint Hose

 

 

7. Poor spraying technique

Even with a machine in perfect condition, the wrong gestures can produce uneven results.

  • Symptoms: visible stripes, overloading at the beginning or end of the pass.

  • Solutions :

    • Hold the gun perpendicular to the surface, at a regular distance (25-30 cm).
    • Advance at a constant speed.
    • Overlap 50/50.
    • Cross passes to even out the coat if necessary.
Purchase an online training course from Airless Discounter Our article on the spraying technique

(German with English subtitles)

 

8. Two strips on the sides of the jet instead of a uniform jet

Sometimes, instead of a homogeneous spray, the spray forms two marked bands around the edges, with a thinner central zone.

  • Causes possibles :
    • The nozzle is partially blocked or damaged.
    • The product is unsuitable or poorly filtered.
    • The pressure is too low to atomise the paint properly.
  • Solutions :
    • Clean the nozzle with the appropriate kit or replace it if damaged.
    • Check paint preparation (mixing and filtration).
    • Slightly increase the pressure until you get an even spray. No chance; dilute the paint to help the machine or get a more powerful machine).
Buy a professional pump on Airless Discounter Our article on bands during spraying

 

 

An uneven spray pattern can have several causes: worn nozzle, incorrect pressure, clogged filters, poorly prepared paint or suction problems. A methodical check of each point will quickly identify the cause and remedy it.

At Airless Discounter, we offer a wide range of nozzles, filters, hoses and spare parts to maintain your equipment. Our experts are also available to advise you on the choice of equipment best suited to your projects.

👉 Need help? Feel free to contact our technical team or consult our practical guides available on the blog.

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Questions or queries?

For any further questions or if you would like to get your hands on one of these products seen in this article, you can contact us on +49 (0) 30 220 15436, fill out our contact form or email us. If you wish to purchase one of the products mentioned above, you can check them out in our online store. You can also visit us at our service base during office hours.