Can someone explain for me how air pressure effects airbrushing? Does a lower pressure cause paint to flow smother, dry slower or what vs a higher pressure. Should some paints enamels or acrylics be sprayed at higher or lower pressures?
Just got a new compressor with air regulator and not quiet sure how to use it.
Thanks to all in advance for your help.
Hi Brownie,
I think a truthful answer would be ‘it depends’. Generally, thicker paints require higher pressures and thinner paints require lower pressures whether they’re acrylic, enamel, or lacquer. What are ‘higher’ and ‘lower’; higher could be as high as 40 PSI or more and ‘lower’ as low as 5-7 PSI or less. That said, most of my AB spraying uses the same pressure regardless of the base paints i.e enamel thinned as I do it will spray at the samepressure as acrylic thinned as I do it. I find I use 15-25 PSI a lot. The guideline for thinning to the consistency of milk is a good place to start. But even with paint thinned as I do it, I will adjust pressure depending upon how narrow a ‘line’ I want to spray - narrower line = closer to surface and lower pressure. Enjoy your new compressor and mix some paint and experiment; there are no rules that say you must adjust pressue to X and thin the paint to Y cuz ‘it depends’.
Thanks Bick. Appreciate it!
I will recommend that you start with your airbrush and compressor user’s manuals. In some cases, the airbrush will have a recommended range of pressures.
The actual pressure setting depends on the equipments as well as the type of paint and thinning.
A good compressor allows you to set the pressure quite accurately. A poorly design, underpowered compressor will show wide pressure fluctuation when you use it.
It would help people to offer better advices if you mention the specific brand and model of your tools.
If you get a fine quality 0.3-0.5 mm nozzle, double action, gravity feed airbrush, start with 15-20 psi. If syphon feed, try 20-25 psi. You will need higher pressure with external mix airbrushes.
You want to airbrush with fine misty sprays in multiple passes. The pressure should be high enough to get good atomization from your airbrush, but low enough to allow control of the trigger. Experiment until it feels right to you.
Like everything else, the new tools will have a learning curve before you get it right. Better quality tools have much quicker learning than poorly designed cheap tools.
Higher pressures atomize the paint better, but that results in it drying faster, so it goes on flatter. Lower pressure makes it go on wetter. The dryer flow makes orange peel and pebbles more likely. I used to use 20 psi for flats, 15 for gloss paints. My new silent compressor only puts out 15 psi. So for a good flat finish I have to dust on several light coats. I can do this all in one session by going over model lightly, returning to starting area and repeating. Gloss finishes are still no problem, of course.
Simple advise is practice a lot, start with low pressure and slowly go higher. Also remember you can always add more paint, taking it off is the problem
Pihil
Thanks Don, just the info i needed!!