Thread: What air pressure to spray?

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Can any one tell me what air pressure to use for spraying acrylic lacquer? I realize that it varies some according to gun type. In this case I will be using a low cost conventional type gun and a low cost touch up/jamb gun.

Thanks! That is kind of what I remembered.

Yup, depends on the heat and the chosen reducer, but it takes 30 - 35 on air pressure. Shoot a few test panels and see what works best before you go for the whole car.

That question can open a bag of worms. It depends on your gun - siphon,hvlp,lvlp,gravity, brand name as well as the paint viscosity(thickness). My Iwata likes 9-16 at the inlet, my Sharpe, 23-25, my Devillbiss, 25-28 and all are hvlp. If you have a Harbor Freight purple gun, 45 to 55 is about right - and your neighbors will hate you for the overspray covering their tomatos. You need to shoot a test pattern and a test panel. The pattern to make sure you have a Bill Clintonish cigar, the panel to prove wetness/coverage. Start with the owners manual for the gun and go from there. Then there is the air quality - will your compressor maintain even flow and pressure - and is it dry air.

" make sure you have a Bill Clintonish cigar, the panel to prove wetness/coverage. "

HA! How many jokes are in that phrase??

And remember that lacquer is not like enamel, which sticks by the "bubblegum" principle. It depends on solvent penetration for adhesion, so it must hit the surface wet. Shoot too dry and it may not stick well.

Shooting with the gun closer to the surface (about 6 inches), or by adding a little more thinner, will help.

If the paint is not atomizing well, turn up the air pressure, and reset the spray pattern.

Are you shooting a solid or metallic?

I am doing some repair work. The hood dropped on a headlight!!!! The paint is a metallic. I have repaired this headlight twice before but some years back. I guess that I am a really slow learner- USE THE HOOD PROP DUMMY!!!

For metallics, it requires more technique than enamel. After it's painted, over-reduce some metallic, reduce the paint, and increase the pressure, and carefully blend to a uniform appearance. (If you already knew this, maybe it will help someone else.)