Flexner of Finishing: Optimize a Spray Gun


A simple test reveals ideal pressure for atomization.
By Bob Flexner
Pages: 54-56

From the October 2010 issue # 185
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Spray guns can run off a compressor or a turbine. With turbines the air pressure is established by the number of “stages,” usually two, three or four. Each stage corresponds to about 2 pounds per square inch (PSI). This seems ineffectively low, but it’s made up for by a huge volume of air, giving rise to the name – High-Volume Low-Pressure (HVLP).

With compressors you have an infinite range of pressures you can use, and it is up to you to set this pressure so your spray gun is optimized for the best possible atomization. If you use too little pressure, you won’t get the best atomization; you’ll get orange peel. If you set the pressure too high, you’ll waste fi nish or stain because of excessive bounce-back.

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From the October 2010 issue # 185
Buy this issue now