air compressor advice - please

Yesterday in the paper there was a Shuck’s Auto Supply add that listed a compressor. I was wondering if it would be good to use for airbrushing. Right now I am using one without a tank that always puts out about as much sound as the blue angels flying low over your house [:D].

Anyway, so I am wondering with the tanks if it would run silent most of the time and if you could take it outside and get the noisy part out of the way and then bring it inside for the quiet airbrushing.

Details on the compressor (as stated in the add):
Contractor Grade 2 HP Twin Tank Air Compressor

  • Maximum 115 psi
  • 4 gal. twin tank with regulator, coupler and 2 gauges
  • 7.75 CFM @ 40 psi
  • 6.6 CFM @ 90 psi
  • Direct drive pump
  • Thermal overload protection
    Compare at $250 and up
    Sale $89

Thanks for any help. The sound of what I am using now is driving my wife and dog crazy, but I don’t want to spend $90 on this and have it be loud all the time too.

Leon

It would probably work fine. I’m not familiar with that specific compressor so I can’t provide any details about the quality or the sound level, but as far as just powering an airbrush it should be fine.

It will most likely have a pressure switch on it that will turn the compressor motor on as needed. When the pressure in the tank drops below a certain point it will come on, when the pressure rises to another point it will shut off. The low cuton point will probably be around 90 - 100 psi with that compressor, so for an airbrush you will have a lot left. To keep the sound to a minimum what you’ll probably want to do is let it charge completely, then manually turn the motor off. When it gets down to where you can’t paint any longer, turn the motor back on and let it refill.

I have a 6-gallon tank on my compressor, and while I’ve never actually timed how long I can go, I’d say I can get at least 30 minutes of solid painting.

HOWEVER … since you already have a compressor, why not just go to Sears or somewhere and get an air tank. They are around $30. Get a regulator for around $20. Air up the tank, paint until it dumps, then fill it up again. Basically the same thing as using a compressor in “Manual” mode.

You might want to look at a Campbell-Hausfeld “Quiet Air” sold at Wal Mart for right at $100. The unit has an air regulator, is a tank, and this is a fairly quiet unit. I still like my Iwata Sprint best because it is very quiet.

Be wary of thr C-H “Quiet-Air” compressors as they are notorious for not lasting long.

Mike

Well I did go ahead and get it, and it seems to work pretty well. However, when I first hit the air it comes out at high pressure and drops to the low amount I want to use (ie drops from tank level say 90psi down to 15-20psi). Is there a way to get it to come out at the 15-20 right from the start? Do I need to buy a different regulator? (the built in one doesn’t seem all that precise)

Thanks for any help.

When I turn mine on, after the tank fills, I might see 5 psi over the regulator setting for the first shot, but there is virtually no volume and when I plug in the air hose it drops down to the proper pressure. My compressor is a Porter-Cable compressor though. I don’t know if most regulators behave like yours or not, but mine doesn’t.

My bet is that, yes, you do need a new regulator. Some of the regulators out there are nothing more than a simple valve. They work ok for things like shop tools, where consistent pressure isn’t that critical. For painting, you need good control right from the start. This means a diaphragm-type regulator that maintains proper line pressure even when the airbrush is not spraying. Home Depot or probably even Shucks should be able to sell you one for $20 or less.

For even less money, Harbor Freight sells one that will fit the bill:
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=32872

But DON’T get this one:
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=36797
This one is one of those simple, valve type units that behaves just like what you already have.

I prefer this type mounted close to your airbrush:

This unit is about $30 and is also a water seperator.
limd21’s advice to check Home Depot, etc is a good idea too.
I have heard that Walmart has them sometimes too.

Mike

Good advice to also have a moisture trap. I keep a simple “inline” filter on mine. Here in bone-dry Colorado, it’s proved to be more than sufficient., but may not be enough for more humid climes or higher-production users.

While we’re at it, here’s a HF unit with a moisture trap, on sale for $19.99:
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=1118
Unless you also buy other stuff from them to qualify for free shipping, it may be better to get a unit from elsewhere. I’m lucky enough to have a Harbor Freight store withing reasonable driving distance.

Don’t get one that also has a built in lubricator. These units are meant for shop tools that need periodic lubrication. Having oil mist in your air lines is bad for painting.

I’ve got a sears air compressor with 5gal tank. There is a drop in air pressure at first for about a second (from 40psi or so down to the 20psi I usually use) but I use that time span to blow a little thinner through the airbrush to make sure everything is gonna work ok. No problem. On a full tank I can spray several 1/48 aircraft or a 1/350 battle ship hull, no need to turn the motor back on.
G.L.

Thanks everyone for the replies (and email Mike). I am going to order a different regulator today with a water filter; hopefully, it will solve the problem (which I guess is more of a nuisance than a problem).

Another question: As I have been looking around I have noticed that a lot of the compressors on the airbrush sites say “oil-less.” Mine requires oil. Did I make a huge mistake in getting this type of compressor? Is it going to give me trouble?

Thanks again for putting up with all of my ignorance.
Leon

No - you should be fine. Oil v. oil-less is how the compressor pistons are lubricated. Oil lubed units, all else being equal, are generally quieter and more robust in the long haul. An oiled unit will not put oil into your air lines.

This is true.

Not necessarily, they can and will put oil into the airline sometimes and that is why a water filter/oil seperator regulator is recommended.

Mike

Mike’s right, I was being less than precise. The filter/trap is needed to ensure clean air.

What I was getting at is that having an oil lubed compressor is not the same as having an in-line lubricator which intentionally supplies a much more significant quantity of oil into the air lines for the purposes of lubricating shop air tools (e.g. an impact wrench). Unless an oil lubed compressor is severely worn, the amount of oil in coming out of the compressor will be orders of magnitude less than would be introduced by such lubricators.

Limd21,

Thanks for clearing that up my friend.
I would agree 100% with your comments. [;)]

Mike

You might want to get an air hose with a moister filter in it. Eventhough you have a moister trap where the air is exiting the compressor moister can still form in the airline to your airbrush as the air cools down. The extent to which this happens depends on temp, humidity and so forth.