One of the key factors to consider when choosing an airless paint sprayer is choosing an airless sprayer that provides enough pressure to properly atomize the paints your considering. Besides pressure, the potential GPM output of the airless sprayer is the second key factor that is often considered when your choosing an airless sprayer. While GPM is important, will cover pressure and why it matters when choosing an airless sprayer.
What Pressure Does for airless paint sprayers
Pressure is the key to properly atomizing materials with an airless paint sprayer. Pressure is also key in being able to effectively pump material over a distance. When considering what pressure will be ideal for your airless paint sprayer, you can check your product data sheet of the products you spray. This will allow you to verify the pressure requirements of your coatings. One additional idea to consider is how much hose you will utilize on your airless paint sprayer. If you will be trying to push material over 100 feet and up vertically, you need to consider using more pressure than what is required on the product data sheet. This is to compensate for pressure drop in your airless paint sprayer hose that occurs over long lengths and heights of hose. For an idea of how much pressure drop can impact your spraying pressure see the chart below. Pressure drop is per 50 feet of hose. By reviewing your product sheet and the hose amount you will use you should be able to determine the right pressure airless sprayer you will need.
Tip Size Flow Rate 1/4” Hose** 3/8” Hose*
.015 .20 gpm 125 psi 45 psi
.017 .27 gpm 140 psi 50 psi
.019 .34 gpm 160 psi 57 psi
.021 .41 gpm 182 psi 65 psi
.023 .48 gpm 204 psi 73 psi
.027 .67 gpm 248 psi 90 psi
Selecting the Right Spray Pressure
After you have chose an airless paint sprayer that will deliver enough pressure the next key with your airless sprayer pressure is using a good operating pressure. Excessive pressure with your airless sprayer can cause excessive overspray but lack of pressure can result in airless sprayer tails (see below). In general you want to gradually increase your airless sprayer pressure until the pressure you have chosen is high enough to eliminate any tails in your pattern and maybe slightly more pressure to ensure pressure drop doesn’t create an issue. By starting low and gradually increasing, you can be better certain you will be using your airless sprayer at an effective pressure without creating excessive overspray.
When it comes to getting the most impact out of airless paint sprayers, you need to choose a pressure that is enough for the paint you will spray. Additionally you should gradually increase your airless sprayer pressure settings until any tails in your spray pattern disappear but not increase much above that so that you minimize overspray and paint waste.