I think there were some threads like this already, but I can't find them now.
I need a compressor primarily to run an impact gun and air ratchet, sometimes an air hammer. The impact and ratchet will be seeing a lot of use, I'll be using them to dismantle cars that I'm parting out.
Since my township will no longer allow me to part out cars in my driveway, I need something small enough to wheel back and forth between my garage and my back yard.
I'd like to find a used, USA made, portable compressor, large enough to do what I need, between $2-300.
What to look for and what to stay away from? Should I be looking at older stuff? I would like something that will outlive me.
the impact is the deal breaker for your price point: you just need a lot of air to run it... i'd say $500 will get you what you are looking for.
100 feet of air hose is pretty cheap if you already have a compressor.
If not, I'd be inclined to buy a good stationary compressor for the garage and 100 feet of air hose. I used to use a 2hp 30 gal portable compressor. You might get one wheel off before having to stop and let the compressor build back up and it wouldn't run cut off tools or grinders. I now run a 5hp 80 gal Quincy. I just did the brakes on the back of my E24. The compressor never cycled.
Edit: The Quincy was $400 and I had to put another $250 in it for parts. Since it's a $2500+ compressor I didn't mind. I'll be able to leave it to my kids.
I agree, the easily portable ones will not have the balls to do what you need. Get a stationary compressor and a long hose. I got a use kobalt 60 gallon upright for $175 a few months ago. It runs tools way better than my old 1970s era 10 gal Craftsman did. 
I have a 5hp gas powered compressor with a 20 gallon tank that works great and runs impacts and such no problem. Not the quietest compressor but truly portable. They are hard to find but they do show up every so often, usually with minor engine problems like bad gas or spark plug. I take it with me in the trailer, very handly at autox events.
I don't know how portable you need, I've got a Porter Cable pancake that I can use an impact with, but not for extended periods of time, I can usually get 2 or 3 lug nuts off before having to wait on it to catch up.
I have an older one of these Speedaire 20 gallon compressors that handles impact duty fairly well, for portability it's got wheels, I can pick it up, but I really don't like to. I bought it from a pawn shop years ago in disrepair, and haggled the price down to $30. After some repairs, and upgrades it became a decent portable-ish compressor for less than $100.
Would a quality 1/2 electric impact be comparable to an air impact? Or is it no contest?
Large, used, portable, made in America...
^That's awesome.
Seriously though, now I'm kind of considering a hulking .5" Milwaukee corded 120v electric impact.
What do y'all think about that vs a lower quality small compressor + air ratchet/impact?
Electric impacts are fair at best. A top quality electric is probably equal to a cheap pneumatic, but no where near as powerful as a top quality air tool.
In reply to Toyman01:
Might work better for my budget though. Those big Milwaukees are ~50 used. They seem to last forever, a guy I worked with this summer had the same one he bought it the late 80s or early 90s.
The mid sized compressors I see used are kind of weird. Either a big tank and a tiny motor (1.5 hp/20 gal), or a big motor and a tiny tank (3 hp/8 gal). I just don't want to drop $2-300 for something and find out it can't keep up with me.
Also, now I'm not even sure if I can get a compressor to do the job I need that doesn't run off 220.
I used a electric impact for years before I bought a compressor big enough to drive a air tool. There is nothing wrong with them, at all. You will probably come across some bolts it just won't loosen. Keep a breaker bar handy and it isn't a problem. The only other concern it they are probably twice the size of a pneumatic.
Do what fits your budget. I used small compressors and limited air tools for 20 years before I bought a big one and it was a case of the right deal at the right time. You might be better off spending the $50 on a electric and saving/hunting for a bigger compressor in your price range.
If you're only using an impact a compressor like that Speedaire will do the job. You're not going to find a 120V electric motor much over 1.5 to 2 (actual) HP, they draw too many amps, anything over that will be 240V.
I own the biggest 18V 1/2" impact that Dewalt makes, it struggles with stuff that my old Craftsman 400 ft lb air impact removes with no effort. I take the Dewalt to the junk yard with me, but still need a breaker bar usually to get stuff broke loose, and rarely use it in the garage.
Another option for portability might be a CO2 or Scuba tank. There's a lot of off road folks that use CO2 tanks as an air supply for their tools/airing up tires when out in BFE. You need a source to fill a tank, but soda fountain CO2 tanks can often be found on Craig's List, then you just need the proper regulator.
^It needs to be portable across about 50 ft.
I'm torn. I see a compressor as a business investment, but really just don't have enough cash to go big.
Here's my rub. The whole idea of a compressor would be to speed up the tear down process, get parts out more quickly, make more money in less time. Seems like that if I get like a 1.5 horse/20 gal or the like, I'll be spending time waiting on the compressor. Doesn't really seem like it's making me more money, you know?
My old Speedaire cuts off at 120 psi and kicks on at 90 psi. 20 gallons at 120 psi lasts a while with my impact, and even with the compressor running it doesn't really slow me down much. I typically keep the regulator set at 90ish psi for my impact.
Having said that, my 60 gallon Kobalt kicks that little Speedaire's rear at everything but portability.
In reply to bigdaddylee82:
What's the hp on the Speedaire?
In reply to RoughandReady:
2
In reply to bigdaddylee82:
I saw that exact compressor on CL for $625.
Choices...
Here's a Devilbiss. 6.5 hp/20 gal. 10.5 cfm @ 90 psi. 240 volt. $250.
$625!?!?!?!?
That's what they sell for new.
That Charge Air Pro is whole lot of compressor on a little tank. I've never had a portable 220V, that could be an issue.
In reply to bigdaddylee82:
Check it out: http://asheville.craigslist.org/tls/4363082850.html
220 presents the problem of either having a really long extension cord or a really long hose. And the problem of me having to touch my incredibly sketchy circuit breaker, which I don't want to do. Electricity scares me, genuinely.
There really isn't that much around. There's a craftsman 5.5 hp/20 gal for $250. Pretty much everything else has a 15 gal or smaller tank.
One thing that peaked my interest was a 3 hp/12 gal Devilbiss for $50. Looks nice in the ad. Says it works and what not. I don't want to be sexist, but it's being sold by a woman on the richer side of town...and I wonder if that's why it's so cheap.
Maybe I don't know what I'm talking about, but I'm thinking I could get the 3 hp/12 gal for $50, find a 20 gal tank and swap over the motor and compressor?
