Under compressure

[Magneto]

Most folk on here seem to have the AS186 - I also have a cheap compressor but mine is the AS196 - that’s a twin piston. The only thing is I cannot get a low pressure to spray - once I dip below 12psi no air makes it out the airbrush - I have to raise to at least 15psi.

Is that normal? Am I reading the gauge correctly?

is the yellow the psi?

 

[stillp]

My AS186 is the same.
Pete

 

[Magneto]

My AS186 is the same.
Pete

The same…?

 

[Mr Bowcat]

You could probably get around the issue with a MAC (micro air control) valve. That way you could leave the compressor pressure higher and just adjust with the valve.

Technically the MAC valve doesn't alter the air pressure (as some smart ass will no doubt point out) but it has the same effect at the brush end.

 

[stillp]

The same…?

Can't get air out of it below about 12 psi.

 

[Magneto]

You could probably get around the issue with a MAC (. That way you could leave the compressor pressure higher and just adjust with the valve.

Technically the MAC valve doesn't alter the air pressure (as some smart ass will no doubt point out) but it has the same effect at the brush end.

Thanks - I will check that out as it looks useful. Although I’m not sure if we are on the same track? When I turn my air pressure down the air totally stops - even without a hose attached

 

[Andy T]

When I turn my air pressure down the air totally stops - even without a hose attached

It's probably reached the lower limits of the regulator. If there's not enough air pressure to counteract the spring operating the diaphragm, it may close completely.

 

[Jim R]

I agree with Bob. I use a MAC valve to have effectively a lower pressure at the airbrush. You can leave your compressor at say 25 psi and adjust the valve to suit what you are airbrushing.

 

[Mr Bowcat]

Thanks - I will check that out as it looks useful. Although I’m not sure if we are on the same track? When I turn my air pressure down the air totally stops - even without a hose attached

As Jim says, leave your compressor at a higher number (I actually have mine around 40) then adjust the volume of air with the MAC valve. You never need to touch the compressor.

 

[Tim Marlow]

Might also be an inaccurate gauge Paul. These things are made to a price and that’s a 100psi gauge. 10% inaccuracy is not unheard of over time even on good quality gauges, so what you are seeing as 12 could actually be zero.

 

[Scratchbuilder]

That end of pressure is the limit on the valve itself.
Two solutions - one is to change the valve itself - spare ones are available from outlets. The other is to buy a MAC valve that you attach between the air hose and the airbrush itself, again available on the interweb stores.
I usually keep the air up to 20psi and then use the MAC valve to ease down the pressure to where I can spray.

 

[Tim Marlow]

Must admit I just put a second PRV (reads up to 50 psi) on the airbrush stand to control the pressure, and wound the one on the compressor up so I don’t have to worry about it. Mine reads zero at zero pressure, though I usually run it between 15 and 20. You do need to remember to put a shot of air through it after adjustments so it settles to the correct reading though. In my working experience they will hang at the previous setting unless you release and reapply the pressure.