Under Pressure!

Tim Marlow

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PRV, pressure reducing valve……

MAC valve, a little screw device that fits under the airbrush on the air inlet line and crimps the air flow.

Basically what I’ve done (and obviously badly explained) is extend the air line connecting the compressor and the PRV so I can adjust the PRV at the bench rather than have to reach to the compressor to do it.
 

Waspie

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PRV, pressure reducing valve……

MAC valve, a little screw device that fits under the airbrush on the air inlet line and crimps the air flow.

Basically what I’ve done (and obviously badly explained) is extend the air line connecting the compressor and the PRV so I can adjust the PRV at the bench rather than have to reach to the compressor to do it.
Not you your explanation, my lack of knowledge about the system. I have seen a few airbrushes with a small knurled knob in front of the airline, would that be what you are referring?
 

rtfoe

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If anything I'll set my pressure with the trigger pulled (dynamic pressure) rather than not (static pressure) but to be honest I can't really see what my gauge says, nor would I trust it anyway, so personally I don't worry about the actual reading.

Thicker paint and greater distance generally means more pressure, so if I'm moving in close or thinning my paint more I'll just keep winding down the pressure until it doesn't atomise correctly (paint comes out spitty rather than a fine mist and it sounds "crackly" coming out of the nozzle) then notch it back up a tad.

Not very scientific I know, but then neither is airbrushing :smiling4:
Totally agree. Pretty much as many ways to airbrush as there are modellers, and they mostly all get good results so to me it’s a pretty bulletproof system. Best way to learn is to play with paint, brush and compressor until it works for you I think.
That's the way I've been using my airbrush too seldom adjusting the psi and only when the paint mixture and coverage requires it and keep it a constant 15 to 20 psi as I work very closely in small areas at a time with very diluted paint and rather use my finger pressure to adjust the amount of air I need.

Cheers,
Wabble
 

Tim Marlow

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Not you your explanation, my lack of knowledge about the system. I have seen a few airbrushes with a small knurled knob in front of the airline, would that be what you are referring?
That sounds like a MAC valve.
 

langy71

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If it helps, I tend to spray at around 10 to 15 psi, and I set this with the trigger pulled, that way I get a constant flow of air at the psi I've set...dynamic airflow as opposed to static pressure
 

Waspie

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If it helps, I tend to spray at around 10 to 15 psi, and I set this with the trigger pulled, that way I get a constant flow of air at the psi I've set...dynamic airflow as opposed to static pressure
I'm usually running at 15-18psi as I tend to use fairly light mixes. Works for me!!

(TBH, it's which needle to use is my dilemma. 0-2, 0.3 or 0.5!! - Guess I'll work it out eventually).
 

Andy T

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Says the Guy that paints cars for a living lol.
Haha, I think that's where it comes from Ian.

Give me a pot of silver and I can get several different shades out of it by varying air pressure, distance, film thickness, air temperature, you name it. I've gotten so used to working on the fly that it spills over into my airbrushing.

Maybe if I were more consistent I'd get better results :thinking:
 
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