What PSI should I set compressor

Alfonso12

You wont need more than 30psi really. I personally spray enamels at 25-30 and acrylics at 15 psi. I have haerd of people who use higher pressures but if your thinning your paint (which you should do for a lot or reasons) I don't think you should need to go over 30

Phil

It will vary depending on a number of variables.

1: Your airbrush. A "gravity feed" brush will typically require less pressure than a "siphon feed" (though in reality, they're all siphon feed).

2: The medium that you're airbrushing. The thinner the medium, the less pressure you will need.

3: The distance from your airbrush to the surface you're painting - the closer you are, the less perssure you will need.

4: What you are trying to achieve. Are you applying an overall base coat or are you detail painting? Are you applying a camo pattern? Your pressure will vary depending on what effect you're trying to achieve.

I will start with the airbrush manual's recommendation which are ususally on the high side, but not far off. Look at Phil_H's list of consideration. Adjust the pressure up and down until you get the best atomization with the minimum overspray.

If the airbrush manual is not specific, I will say 15-25 psi for gravity feed and 20-35 psi for siphon feed. The pressure reading is before you push on the airbrush trigger. The pressure reading on a high quality compressor will change little when you start the airbrush. Typical one can drop up to 2-3 psi in reading. If it fructuates more than that, the pressure gauge is not install properly or defective.

It helps to give the brand and model of your compressor when asking for recommendation.

With my older compressor, I used either 15 or 20, using 15 for glossy finishes and 20 for flats.  My new compressor (a super quiet one) only gives me a little over 15 during flow. It works fine for gloss, but I had to adapt my style a little with the flats. I have to get a little closer and get a little less coverage so it takes me a little longer, and I have to thin flats just a little thinner than I used to.  But in general I would recommend the 15-20 range.  You can adjust for different pressures by different thinning ratios and by changing distance of nozzle to surface.

One general thing I have found is that many folks who have trouble airbrushing try to use it as a large volume spray gun.  An airbrush is really more of a brush that just doesn't contact the surface.  Don't be in a hurry, take your time and cover small areas at a time with lots of overlap.  Airbrushing is more like regular brushing than using a spray gun.

If your airbrush is a Paasche Model H you might need 30 PSI or a little higher but otherwise what others have said is good advice. For most of my airbrushing, I set the PSI to around 20 and adjust up or down to get the spray pattern I want without concern for the actual pressure. Thinner paints and close painting require less pressure.

The best pressure is the ones that produce the best looking surface to you when the paint dries. If you are not sure, talk to other modelers by attending a local club or go to the local hobby shop.

I have found best results at low pressure, 15 psi or less.  It gives me good control and minimizes overspray.  For cleaning, however, I blast the solvent through at 45 psi or more.