What to Look For in an Air Compressor?
12 replies to this topic
Posted 22 August 2009 - 11:52 AM
Ok so i have my airbrush picked out, now its time to look into compressors.
from what has been said to me, i need something with 30-40 psi working pressure (what exactly does this mean?), a moisture trap (is this something you have to replace periodically?), a good regulator (what exactly is this? is this just how you set your psi?), and preferably a storage tank so the compressor isn't running constantly.
could you guys help me answer these questions? what is a good compressor that could be found at Lowe's, Home Depot, Sears, etc that would work with an airbrush?
thanks for your help guys.
Posted 22 August 2009 - 01:15 PM
A compressor pumps up to its maximum pressure when you turn it on, then cuts off. When you activate your airbrush, the pressure drops. The working pressure is the psi your compressor sustains with the airbrush running continuously. For large tool compressors, you may not even be able to notice the difference running an airbrush. For a small Chinese airbrush compressor, you definitely will. It may pump up to 35-40 lbs max psi (max psi is the always higher and so it's what they always advertise) but when you hit the trigger, the working pressure may drop to 15 psi - which is sub par.
When air is compressed, then allowed to expand into your airbrush hose, the water vapor it carries condenses into droplets. The moisture trap collects that so it doesn't reach your airbrush. Most traps collect the water into a reservoir and you can empty them, so are permanent. Some use water attractive crystals that turn blue as they become saturated. You have to change the crystals in that type.
A pressure regulator is a simple valve, like a water faucet, but for air. They often are sold with a pressure gauge attached.
You can get all this stuff, plus a tool compressor and the fittings to connect it, and some PTFE plumber's tape, at most home centers. Bigger is better if you want a compressor that can be used to drive other tools. But most bait builders are satisfied with a small tool compressor that develops something in the 100-120 psi max range and has a 1 or 2 gallon air storage tank. Prices run $50 on up, depending where you buy them, the capacity, and the quality. The bigger the storage tank, the less often the unit will run so the quieter it will be. But keep in mind that a tool compressor, and even most small airbrush compressors are not quiet.
Posted 22 August 2009 - 05:10 PM
Thanks Bob, that was a lot of help.
so the pressure regulator is what you use to select the pressure of the air coming out of your airbrush. if i wanted to shoot 20psi from my airbrush, i'd adjust this setting at the pressure regulator?
Posted 22 August 2009 - 06:15 PM
does this seem like a good air compressor for airbrushing?
Quiet Air Compressor 3 gallon - FP2047 at The Home Depot
do these things have the pressure regulator built in? is that what the guages on it are for?
Posted 22 August 2009 - 09:30 PM
My answers are Yep and, uh, Yep. I can't speak to the durability of any particular tool compressor I haven't used, but that one seems like it's in the ballpark. I like that it has a 3 gal tank versus 1 or 2 gals on some compressors. The bigger the tank, the less often the compressor runs and the longer it lasts, all things equal. That black knob and dial on the side are the pressure regulator and gauge, btw.
Posted 22 August 2009 - 09:32 PM
The regulator actually controls the air pressure going too your airbrush, and yes, thats where you'd adjust it when you want more or less pressure.....a regulator is a must on any sizable compressor since most will reach 100-120psi before they shut off, and you don't want that much pressure on your little airbrush hose....or the air valve inside the airbrush for that matter....one or the other would most likely rupture at some point if they were allowed to run at full tank pressure.
As pointed out the water traps have drain valves that allow you to drain the traps.....they do have some type of filter media in them to hold the moisture back, and most will eventually clog up and need replacing....mine has a white stone looking thing, kinda like an airstone that hangs in an aquarium only bigger......I think there is alot of different types, but in most cases I believe they take years to need replacing.....i've been running mine close to 15yrs and its just now getting to the point that I should replace it....but what i'll do is just purchase a new mini regulator/water trap combo so i've got a new regulator....they aren't too expensive.
The unit you posted would most likely run an airbrush fine.....it has a built in regulator with two gauges....one gauge is mounted in front of the regulator and shows you the tank pressure and the other guage is mounted past the regulator and shows you the pressure your allowing to your tools or in this case to your airbrush.
Edited by 68KingFisher, 22 August 2009 - 09:40 PM.
Posted 22 August 2009 - 11:06 PM
ok thanks for clearing things up.
so not all air compressors have the regulator built in? it seems only logical to have them already on there...
Posted 23 August 2009 - 12:05 PM
MOST compressors sold commercially come with a regulator and dial, as a safety feature on units that develop enough pressure to be hazardous, and to allow the user to dial in the required pressure for different air tools. They aren't "built in" per se. Compressors are basically an assemblage of parts and the regulator is just screwed into the air outlet.
Edited by BobP, 23 August 2009 - 12:07 PM.
Posted 23 August 2009 - 02:33 PM
ok, that's what i meant by built in, meaning, you didn't have to go and buy an aftermarket regulator for your compressor.
Posted 28 August 2009 - 03:53 PM
the one in the link i put up a few days ago is an online only deal, but yesterday i went into home depot and found this one:
Husky Husky 1.5 gallon Air Scout Compressor - 41214 at The Home Depot
it seems like it should work fine for an airbrush, and it got good user reviews.
what do you guys think of it?
Posted 28 August 2009 - 04:18 PM
Like you said it got good reviews for the most part....I'd imagine it would work ok, and the reviews that mentioned noise levels said it was quite.....it would be nice to listen to it run before ya buy it though....Think one of them HD associates would fire one up for ya?
I couldn't help but notice this unit shown at the bottom of that webpage and thought i'd point it out since it had twice as big of tank for less money....they even went so far as to mention "airbrush" in their discription of uses....it doesn't have quite the muscle but its got the bigger tank....that translates to less run time.....might be worth doin a side by side comparison at the store. Quiet Air Compressor 3 gallon - FP2047 at The Home Depot
Edited by 68KingFisher, 28 August 2009 - 04:19 PM.
Posted 29 August 2009 - 12:15 PM
thats the air compressor i mentioned on the other page. i like that it has the bigger tank and all, but it is an online only product, and i would rather buy one in a store.