This article covers the main factors for choosing the right airless nozzle, using several examples from machines like DEMA, Rotenbach, Dino Power and other airless paint sprayers, that you can often find on Ebay and Amazon. We also have information and links for brands such as Wagner, Graco and FARBMAX. Selecting the right airless nozzle will ensure your machine performs optimally, has a longer life span and reduces the costs of replacing spare parts or maintenance.
The purpose of the airless nozzle is to determine the fan width of the spray and the flow rate. The pump of the machine produces the pressure, which acts against the size of the hole of the airless nozzle.
Each nozzle will have the follow general specifications:
- A plastic handle – shaped and colour coded. The arrow denotes the direction of the spray and most companies have colour coded tips as a compatibility guide.
- A (bore) hole size, usually expressed in inches.
- A 3-digit or 4-digit number, which represents the bore hole size, the fan width and spray angle.
- Their recommended applications. Some airless nozzles are only used for certain applications, others are recommended for particular jobs, but do have more flexibility for other projects too.
- Some airless nozzles will have additional abbreviated letters to further describe their main features.
As a quick example: let’s consider an airless machine with a spray capacity of about 1 liter per minute; from the technical data sheet, such a machine can be used with a nozzle 515 at most. That means it is suitable for lacquers and interior emulsion paint. These machines are not suitable for painting facades, or applying mastics or roof coating, because they lack sufficient power. But what does the 515 number mean? Let’s find it out…
Understanding the Airless nozzle number
The 3-digit number (5-1-5) tells you the hole size in inches, the fan width and the spray angle, it can deciphered as follows:
The number 5 in front (515)
The first number 5 indicates the opening angle with which the airless spray gun will spray the material. To calculate this angle simply put a zero in front of the digit, so for 5 we have 50 degrees, 4 stands for 40 degrees, 3 for 30 degrees, and so on and so on. To be precise the angle is the spread at which material is expelled through the hole with this angle of atomization.
Take that same number in front and multiplying by 5, will give you the fan width when the spray gun is held perpendicularly, 25cm from the surface. This means that for our above example, a 515 airless nozzle will produce a spray pattern fan width of 25cm (5 x 5 = 25).
If I want to paint a big area, for example a wall, then a spray angle as wide as possible is preferable, with which it can cover a larger surface.
For spraying in more detail, for example beams or window frames, a nozzle which allows for more accurate atomization is preferable. In this case, we would choose an airless nozzle with angle of 20 degrees. For example, the airless nozzle numbered 211.
A combination of three numbers appears on the head of the airless nozzle. We have already deciphered the first digit of this 3 digit number. That is, the first 5 for the nozzle 515. Now for the second two…
The following two numbers (515)
The 1 and 5 make up the number 15. This indicates the diameter of the hole through which the material is sprayed. In this case, 15 stands for 0.015 inches. To convert inches to centimetres, multiply by 2.5 times the particular number. For example a 0.019″ hole is equivalent to a 0.048 cm hole, roughly half a millimetre.
Max. tip size 0.051” or 1.2954 mm
To sum it up: when spraying interior emulsion paint, I use the 515 nozzle, since I need a larger diameter to do so. For example, 0.015 inches, which corresponds to 0.38 mm. When I have a particularly fine material, I would need to use a smaller nozzle, with a (bore) hole of 0.009″.
Choosing the right airless nozzle depends on the paint or material you are using – first check the data sheet.
Modern materials now contain instructions for the compatible Airless nozzle sizes, and each manufacturer has a table with technical specifications for their partcular airlessnozzle product range. This data sheet can be compared to the package leaflet of medicine. You will find information on their use and recommendations for which products the airless nozzles can spray.
FARBMAX Spray Tip Table
Take a look at our airless nozzle chart to give you an idea of which nozzle works best with your airless equipment. For example, types of material: lacquers, interior paints, for facades, … and which airless nozzle is recommended for each.
Choosing the right airless nozzle general categories
Nozzles can be broadly defined as falling into one of 4 categories:
- Low pressure for interior paint jobs and small projects
- Professional applications for interior and exterior paint jobs in the residential and commercial sectors
- Heavy-duty work for painting jobs with high viscosity and textured materials.
- Specific-use nozzless such as those used for road markings and sports fields.
Examples of nozzles you can use:
The 211 nozzles are used to work with light lacquers and spray more accurately. For example, to paint beams and window frames.
To paint larger surfaces, such as ceilings or tables, it would be more appropriate to use a 411 nozzle with lacquers or paints / interior materials
To paint rooms or houses, a 515 nozzle would do best.
Which nozzles are suitable for these paint sprayers?
Examples of nozzles suitable for the paint sprayer and the gun featured in the video are:
FARBMAX Silver tip. Price: 16,80 € + VAT
Wagner TradeTip 3. Price: € 38.48 + VAT
Graco RAC V. Price: 48,98 € + VAT
Examples of nozzles NOT suitable for this gun: nozzles of the Graco RAC X series (the blue ones) are not suitable for this gun.
Is too much paint being delivered? Use a smaller nozzle or increase the angle
Airless paint spraying requires you to hone in your skill for adjusting the pressure setting to optimally suit your material and job application, however choosing the nozzle matters too! If you feel too much material is coming out of the gun, consider lowering the pressure or changing the nozzle. Just remember:
Going from a 419 to a 519, will increase the fan width and spray angle.
Going from a 519 to a 517 will decrease the (bore) hole size from 0.019″ to 0.017″.
Since you may not want to compromise on the spray angle and fan width, since the area you are working with is likely remaining fixed, your option then becomes to reduce the hole size.
What happens when the nozzle wears out?
Are you noticing:
- The spray pattern developing bands of lighter and darker areas
- A smaller fan width, as if the angle of spray has decreased
- You are running out of paint faster than usual?
A worn out nozzle is noticeable when “tails” emerge on either ends of the spray pattern, when the fan width decreases or when more paint is being required to cover the same surface area.
This is due to the nozzle losing its shape and/or getting clogged. A new nozzle is shaped much like a hot dog, it is long and narrow with rounded edges. As its being used the nozzle hole widens and shortens, becoming more like a burger bun. More material is then dispersed in the middle and less on the outside. The paint delivery rate and surface coverage is compromised too.
Airless nozzles are one of several common spare parts that are replaced frequently with regular use. We have additional posts that cover spray guns, filters and different accessories necessary for the correct operation of your airless paint sprayer.
If you have any further questions, please leave us a comment and we will get back to you as soon as we can.