Air compressor, what kind?

[Balog]

Looking to get a small to medium air compressor. Usable for inflating tires etc but also able to run air tools as needed. I'm thinking an older used one off Craig's List will be the best value, but don't really know what to look for when looking one over. Brand and model recommendations? Things to look for or to avoid?

[Boomhauer]

Avoid rusty tanks that never or rarely got drained of water.

[charby]

I have a 5hp single stage 20 gallon air compressor in my garage, it is ok for intermittent heavy air tool use but nothing continous. Works really great for nail guns, air brushes and inflating tires. When I use my air ratchet it does run a lot but will keep up if I don't go all crazy with it. I've gone to a cordless drill for a lot of assembly work and use a hand ratchet to break bolts loose and to the final tightening. Torque wrench when needed.

If you want to do some serious painting or running impact wrenches you need to look at large air tank, like 100-200 gallon or bigger. These tools can take a constant volume of air at a set pressure.

[dogmush]

What kind of tools? That makes a big difference.

My normal advice is to buy the biggest one you can afford as you'll find yourself wanting the extra capacity later. Really, you will.

Used homeowner grade? Look for Campbell Hausfeld or Ingersoll Rand. Oilless would be better, because the previous owner didn't do any maintenance anyway, and no rust/water marks.

Basically look for one that looks like it sat in someone's garage, not one that traveled to jobsites.

[Unisaw]

I'm not sure which tools you want to run off of it but I really like my 1 hp compressor made by Rolair.  It is extremely quiet.

http://www.youtube.com/therealrolair

[never_retreat]

The oil less direct drive types tend to be as loud as a chain saw.

[zxcvbob]

I had an ancient Quincy compressor with about a 35 or 40 gallon tank (weighed a ton) and a 1.5 HP 240V motor.  I probably had the wrong size pulleys on it so the motor was overloaded a little, but it never ran continuously so I got away with it.  One winter I started it up and a connecting rod broke and tore up the whole pump.  :sniff:

I replaced it with a 5HP Coleman (?) with a 20 gallon tank, and the motor is spec'ed for a 20A 240V circuit.  And it has tripped the breaker once or twice.  It doesn't even come close to putting out the air that the old Quincy did.  No, the Quincy wasn't a 2-stage, it was just efficient.  As far as the CFM specs and all that, air compressor manufacturers lie.  (that was the main point of my "tl;dr" story)

I bought my dad a Porter Cable portable compressor a couple of years ago for Christmas and he loves it.  It's the one with the 6 gallon "squashed sphere" tank and an oilless pump on top.  I was impressed enough with it that I bought a refurb for me and another for the local Southern Baptists disaster relief trailer.  You can find them on sale sometimes online for about $100, or pay full price at the box store for about $150.  Don't get the slightly smaller Harbor Freight compressor that looks the same; it's weak.

I will repeat DM's question, "what tools?"  A grinder takes a lot of air.  Filling a tire doesn't.  Paint sprayer can go either way depending what kind of mixer it has.

[Nick1911]

Right after I bought my house, I didn't have a lot of money but was doing enough work to justify air tools. I bought a little cheap Harbor Freight unit, similar to this: http://www.harborfreight.com/air-tools/compressors-oil/2-hp-8-gallon-125-psi-portable-air-compressor-67501.html

I figured I'd kill it and when I did, I'd upgrade.  I didn't expect it to last 6 months.  I've had times where my air use kept the motor running nonstop for hours.  I never change the oil.  I rarely drain the tank.  It's run hard and put away wet.

Five years later, still chugging along.

[charby]

Right after I bought my house, I didn't have a lot of money but was doing enough work to justify air tools. I bought a little cheap Harbor Freight unit, similar to this: http://www.harborfreight.com/air-tools/compressors-oil/2-hp-8-gallon-125-psi-portable-air-compressor-67501.html

I figured I'd kill it and when I did, I'd upgrade.  I didn't expect it to last 6 months.  I've had times where my air use kept the motor running nonstop for hours.  I never change the oil.  I rarely drain the tank.  It's run hard and put away wet.

Five years later, still chugging along.

Thats awesome, makes me not so scared to run the piss out of mine.

[Monkeyleg]

I did my restoration on my Jag using a Craftsman 5 hp 20 gallon model. That was 30 years ago, and it's still running just fine.

I found that it wasn't up to the task of running air chisels, impact wrenches and even paint guns continuously. I had to stop every few minutes to let it catch up.

If possible, find one that runs on 120 rather than 220. It's a pain to have to run 220 to a garage that doesn't have it every time you move.

[HankB]

I have this little unit I purchased on sale from Lowe's:

http://www.lowes.com/pd_253750-70-C2002-WK_0__?productId=1072413&Ntt=compressor&pl=1&currentURL=%3FNtt%3Dcompressor&facetInfo=

It may be the same model that zxcvbob wrote about a few posts up. It's portable - you can pick it up and carry it around with one hand.

It works perfectly for things like filling tires, blowing out a dirty rifle action, powering a brad nailer, etc. I imagine it would be fine for a small airbrush (the little ones used for model making and such) but it doesn't have the capacity to power a full size spray gun or most "full size" air tools - at least not for long.

[zxcvbob]

Yeah, that's it

[RocketMan]

I've got a 4hp 13 gallon standard duty Campbell Hausfeld that has stood up well. Bought it at Home Depot about 15 years ago. Use it for inflating tires, airbrush work, miscellaneous stuff.  Going to use it to paint the house this summer.

[Balog]

Right after I bought my house, I didn't have a lot of money but was doing enough work to justify air tools. I bought a little cheap Harbor Freight unit, similar to this: http://www.harborfreight.com/air-tools/compressors-oil/2-hp-8-gallon-125-psi-portable-air-compressor-67501.html

I figured I'd kill it and when I did, I'd upgrade.  I didn't expect it to last 6 months.  I've had times where my air use kept the motor running nonstop for hours.  I never change the oil.  I rarely drain the tank.  It's run hard and put away wet.

Five years later, still chugging along.

Good to know, that's an attractive price.

As for air tools, I have none at the moment. My eventual plan was for a grinder and pneumatic chisel to start off with. I got used to air grinders when I was working in a machione shop and now the electrics annoy me.

[roo_ster]

Be sure your garage circuit can handle the load.  My neighbor has a 14 or 15amp draw compressor with a 100gal tank that trips my breaker when I try to use it.  15amp circuit.  The little 1gal 1hp (something like that) Campbell Housefeld I bought  runs OK, but has not the guts to do anything I want for long enough.  Wish I woulda bought something with an 8-10 amp draw with a big honking tank.

[zxcvbob]

Wish I woulda bought something with an 8-10 amp draw with a big honking tank.

Add a big honking auxiliary tank.  Water heater tanks are hydrostatic-tested to 150 psi; not sure if they are safe for compressed air service, but I dunno why not.  'Cept hot water is not compressible...

[never_retreat]

This is very commonly done. I recommend a propane tank instead. At least you know its not rested out on the inside.
I've heard of the Amish using oil tanks, dig a hole stick it in and backfill for cement. Makes it strong enough to hold the pressure.

[41magsnub]

This is very commonly done. I recommend a propane tank instead. At least you know its not rested out on the inside.
I've heard of the Amish using oil tanks, dig a hole stick it in and backfill for cement. Makes it strong enough to hold the pressure.

Do they fill the tank with horse driven bellows?

[Nick1911]

Do they fill the tank with horse driven bellows?

Diesel engines don't have spark plugs 

[never_retreat]

Do they fill the tank with horse driven bellows?

The Amish use compressed air a lot, usually made by an engine driven compressor. Same thing with an engine driven line shaft running there other shop tools.

[Brad Johnson]

I picked up a used compressor a couple years ago.  Older model with a regular change-the-oil style old school low speed compressor.  Had several gallons of water in the tank, but after draining it and leaving the petcock open for a couple weeks to let it dry, it doesn't seem any worse for wear.  I got it cheap (actually free) because it refused to come if there was any pressure in the tank.  A load jenny solved that.  Throw in an oil change and a can of spray paint and I have about $30 in it.  It won't win any awards and may keel over any day, but it works for my needs.

(For you non-old folks, a load jenny is a pressure relief valve.  It depressurizes the compressor line when the compressor stops.  If the compressor stays pressurized there's too much starting load for the motor.)

I'd say keep an eye on craigslist and see what pops up.  If the unit is relatively new and comes from somewhere that it didn't get used to death it'll probably be okay for your needs.

If you get a new one, bite the bullet and get a good one.  Pay a couple extra bucks and get one that will last.  Chances are that hundred or so more in price will be the difference between a unit that will fail in four or five years, and one that your grandkids will still be using in forty or fifty years.  I'd suggest staying away from oil-less units and getting something with an old-fashioned low-speed pump.  Good ones can be rebuilt almost indefinitely, that is if they ever wear out at all. Dad's garage compressor is a 30 gallon Ingersoll that was given to him and Mom as a housewarming gift... in 1962.  Granted, it needs some, well actually a lot, of TLC, but it still works for airing up tires and running the occasional air wrench.  I put chalk most of that longevity up to the relatively low compressor speed and pressure limit.  Low component stress = long life.

A little Google-fu turned up this...

http://www.sears.com/ingersoll-rand-20-gallon-air-compressor-vertical-tank/p-00989225000P?prdNo=2&blockNo=2&blockType=G2

Brad

[geronimotwo]

i have an older one of these although mine has a grey tank.

http://www.ebay.com/itm/DEVILBISS-MODEL-NO-PAFAC153-1-3GALON-1-5HP-AIR-COMPRESSOR-/350732034432?pt=LH_DefaultDomain_0&hash=item51a9422180

 as i recall, mine was only $150 at bj's and it's small and easy to one hand carry.  i have used mine for 15 years doing light contracting and it will keep up with my framing and roofing guns.  it does not have the volume for using a 1/2" impact wrench, but can run an air ratchet for an occasional bolt or two.  it likely would not run an air chisel or grinder for very long.  the only problem i had with it was when i hit the aluminum tubing coming from the compressor to the tank and it cracked at the fitting.  even then i only needed to shorten it and use a new compression sleeve.

if you are looking for something bigger, i highly recommend speed-air products.

[Sawdust]

I bought a 60 gallon Campbell-Hausfeld about nine years ago.

Runs everything fine; my biggest demand is are HVLP painting guns.

It was so nice not to have to listen to that damn loud pancake compressor any longer.

It's been a good, trouble-free investment.

Sawdust