Air Pressure for Acrylics ?

This brand really prefers a primer, eg I really like their Poly-eurethane primer available in lots of military colours, info here:  http://www.acrylicosvallejo.com/gb/primers-gb.html 

read up about ModeAIR & ModelCOLOR on their website.

These are sprayed un-thinned & at a higher pressure than normal & go down really well.

With Vallejo, start low air pressure & then turn it up a bit.

I find that with Vallejo AIR, i thin a little, & Model COLOR, thin a lot.

Then it's a combination of  air pressure, viscosity (of paint), brand of thinner, distance from target, if target has been primed, humidity, heat, brand of air-brush, nozzle size, (0.5mm works better for me with acrylics) & what combination worked yesterday MIGHT not work today!

Ther above might just be me, & your milage may vary...

There a few (!) tutorials on you tube, search & learn, don't expect to do show winning stuff first time out.... but most importantly, experiment & learn... & have fun!

I'm not a big user of acrylics, so keep this in mind when I talk about the subject.

However, I think many modelers use their airbrush at too high a pressure.  They want the airbrush to be more of a spray gun than a brush.  I get my best finishes at lower pressure, small distance, which means very small coverage area.  That is, the airbrush is indeed more like a brush, but one that does not leave brushmarks.  I typically spray enamels at about 15 psi, sometimes up to 20 for flats.  I generally use the same pressure for acrylics, because I thin them so I can use those pressures, which I am more experienced with.

i spray 12-15 psi. 20 pounds max. same goes for enamels or acrylics. the closer you spray the lower the pressure should be. all paints should be thinned to the consistency of milk. other like it more thinned. depends on the person. 

I do not use Vallejo. I use mostly Tamiya or Model Master Acrylic, thinned. A 17 psi pressure work for me most of the time. I may adjust it up or down a little depending on the paint. For spraying larger areas such as applying primer, higher pressure (25-30 psi) can be used.

I must qualify the pressure value because not all the compressor regulator measures it accurately. I set the pressure at 17 psi before I spray and the reading does not change more than 0.5 psi when I push down on the trigger of the airbrush. I spray in very fine misty coatings by making multiple passes. It is important to get high enough pressure to get good atomization, but not too high to get runny paint.

If the pressure reading changes a lot when you start pushing and pulling on the trigger, it could be one of two conidtiions. If your compressor is very low powered, you may not get sufficient pressure for good atomization. If you get a powerful compressor and the reading drops, you may be spraying at a higher pressure than it actually reads.

The bottom line is experimenting until you get a smooth and even coat everytime. With proper pressure, your airbrush should be very responsive to your trigger action.

If you have a pressure setting recommendation, please, state what compressor you use. At least, mention the pressure reading to be the one before or after you push the airbrush trigger and the difference between them.

I've been using an Air Star V for 7 years now, with no problems at all. For most acrylics, 15-18 works just great. I use mostly Tamiya and Polly Scale. I used Vallejo for the first time on my last build. It likes a slightly lower psi, thinned with Future. Try 12 psi.

panzerpilot

I've been using an Air Star V for 7 years now, with no problems at all.

Badger recently renamed the Thayer and Chandler Air Star V T909 compressor as "Badger Aspire Elite TC909" and lowered the price. The horsepower went up from 1/8 to 1/6 and maximum pressure from 40 psi to 57 psi. The case style also changed. Did they change supplier? Anyone knows the story behind it?