Silly Compressor Question

If the water trap is between the compressor and the regulator, the gauge on the regulator will indicate the air brush outlet pressure, which is what you want.

Compressor, water trap, regulator/gauge, airbrush, connected in that order.

Griffin

Following up on my silly airbrush question:

I have a moisture trap on my compressor and the literature says there should be a 5psi pressure drop through the trap. Can I put the trap before the regulator so the regulator gives a more "actual" reading?

Thanks.

What kind of compressor do you have? What type of moisture trap do you use with it? The 5 psi pressure drop is huge. If you have a very high power tools compressor, it may corresponds to a 6-10 SCFM flow at 90 psi or so. An airbrush draws neligible amount of air and you should hardly see any pressure drop. In a typical combined regulator/moisture trip unit sold for airbrush, the air passes through the trap first. The pressure gauge measures the pressure applied to the airbursh. In a good regulator, the pressure reading stays constant between no flow and full blast of the airbrush.

I have a regular air compressor, 2-gal tank (I think), not an airbrush compressor. I'll see about posting pics up tonight.

Griffin

I have a regular air compressor, 2-gal tank (I think), not an airbrush compressor. I'll see about posting pics up tonight.

The pressure drop is a function of amount of air flow (pound per minute or cubic feet per minute). No matter what compressor or moisture trap you use, the pressure drop should be very, very small for the amount of air your airbrush draws.

When your compressor or moisture trap manual mentioned 5 psi pressure drop, what was the airflow they quoted?

keilau

When your compressor or moisture trap manual mentioned 5 psi pressure drop, what was the airflow they quoted?

Here are the pics I promised the other night:

Current Set-Up:

The case liner for the trap says:

• 22-SCFM flow @ 90-PSI inlet. 5 PSI pressure drop
• 64-SCFM max flow capacity @  90-PSI inlet.

Griffin

keilau:

When your compressor or moisture trap manual mentioned 5 psi pressure drop, what was the airflow they quoted?

The case liner for the trap says:

• 22-SCFM flow @ 90-PSI inlet. 5 PSI pressure drop
• 64-SCFM max flow capacity @  90-PSI inlet.

Most manufacturer do not specify the air flow their airbrush needs. But you can take a clue from the recommended compressor such as in this Paasche Talon manual. Typical range is 0.2-0.5 CFM which is 1-3% of your trap's specification of 5-psi. Do you expect more than 0.02 psi pressure drop when using an airbrush? I doubt that the regulator gauge will have such accuracy.

Your setup is fine as is except for the noise.  Are there improvement you can make? Yes.

BTW, how do you adjust the airbrush pressure when airbrushing? Using the regulator upstream of the moisture trap or a second regulator near your work bench? How fine is the adjustment and how repeatable is your setting? If you are happy with what you get, don't change anything.

It's definitely noisy. I work in the basement with ear plugs in.

I adjust the pressure with the gauge upstream from the trap. I set it about where I want it, test on some scrap and then get to it. I was shooting around 18-20 PSI but I'm thinking about experimenting in the +/-15 PSI range to see what that's like.

I am totally new at this so I've only primed a model and a few plastic bottles so far.

If I were you, I will move the Clarke Air compressor to the garage for other uses and get myself a nice, quiet airbrush compressor.

It is hardly enjoying a hobby when you have to plug the ears in.

I just bought a Habor Freight job and it is quiet. Got tired of jumping out of my shoes when my pancake compresser fired up. Normally I would fill the tank and shut of the unit and then spray, but the last time I forgot and it came on and I didnt have the the cover on the airbrush bowl paint went up in the air. Its in the garage now ready for the brad nailer.

Bill

Another option:  Many of the guys in my local IPMS chapter use a CO2 tank, with a regulator and gauge.  Absolutely silent and lasts a long time.  When it runs out, they get it refilled at a local welding supply shop.

Normally I would fill the tank and shut of the unit and then spray . . .

I think I may try this for now.

I think I may eventually replace my compressor and my AB. I'm currently using a second-hand Aztek but, if the hobby sticks this time, I may look into getting a better AB. The only problem is the local availability. No one seems to carry anything but the Aztek. When I get the new AB, I might as well get a quiet compressor to go with it.

Your Aztek and compressor should do an adequate job for the hobby. Yes, it is wise to wait to spend more on tools until you are sure the hobby sticks this time.

I spent $120 for the Aztek, Compressor and a Paasche AB a few years ago. The compressor alone has paid for itself with tire inflations and filling the kids' inflatable pool.

It seems that I am actually getting pretty consistent in spending time at the bench so that's promising. I've been enjoying being here in the forums and being "around" the hobby a bit too.