Shop Air Compressor

[JasonL]

I'm thinking about purchasing an air compressor for my shop. Does anyone have suggestions about things to avoid or look out for? I'm just starting my research and thought the experts could help out. Thanks! Jason

 

[MadReferee]

Do a search in "Other Forums" for "air compressor". You will find that your question was asked and answered several times in the past few years.

Here is a link to a rather detailed discussion that you will find helpful.

Shop Air Compressor discussion

 

[Av8r3400]

I have a direct drive 5hp, oil less, 30 gallon, 220 volt Craftsman. It is cheap and very, very noisy, but, it has functioned for most of what I needed. (Airing tires, air nozzle for blowing water off motorcycle, etc.)

If I were to buy a new compressor, I would look for a "two stage" iron compressor with a separate (Baldor /forums/images/graemlins/smile.gif) 220 volt motor on at least an 80 gallon vertical tank. Separate motor = not direct drive, repairable and upgradeable. Iron compressor = durability over aluminum, I'm more into quality as I grow older. Two stage = 175 psi with higher volume (running a sander or polisher or impact gun uses ALLOT of air). I would use more of my air tools if I had a better compressor.

A compressor with a spin on filter has pressure oiling in it, and will be the absolute best, but, it will also be the most expensive. /forums/images/graemlins/frown.gif

Just my opinion.

 

[BB_TX]

Like Av8r2230 I have a direct drive Craftsman I have had over 15 yrs and never a problem. Although mine is only 25 gal, 120 VAC. But it does all I need. Air up tires, run my impact wrench, rotary tool with wire brush for cleaning metal, air blow gun, etc. If I used tools needing high volume of air I would get a better one, but don't have that need.

 

[varmint]

As a guy who's had several air compressors, I have to say that my son was smarter than me: he bought about what Av8R2230 recommended, from Amazon... except he got one with a 60 gal. tank, upright, for about $400 delivered. It makes a useful amount of air, and is much quieter than my units. Almost quiet enough to use without ear muffs, depending on where it is! Unless you are going to use it 40 hours a week, I'd say get oil-free. Harbor Freight has a pretty nice HVLP spray gun for $50 when it's on sale, FWIW.

 

[mbrule]

Consider your usage and CFM ratings, most any compressor will deliver the PSI that you require for any job. CFM is the important rating! The only other advise I have, is buy the biggest and best compressor that your budget and space allow. Then you won't be sorry down the road.

Matt

 

[Spiffy]

If you're just filling tires, get whatever you like cheap; maybe even one of those twin tank portable "contractor" compressors for around $100.

If you have any airtools, Av8R2230 gave very good advice. Spend the extra now, and you'll actually enjoy your airtools. If you're just using air-ratchets 10cfm will be more than plenty. If you have a sandblaster, or sander, polisher or other high CFM tool (don't be fooled on false advertising here either; it takes a lot of air for any material removing activity) get closer to 20cfm @ 100psi.

Whatever you choose, please don't be fooled by "Peak HP" marketing tricks. The 20cfm mentioned only takes 5HP [roughly 20Amp @ 220V or 40A @ 110V]; but most "8HP" compressors wont touch it. CFM free air (not displacement) at a given pressure is what to look for; if it correlates to the motors rated current draw [not peak] then you're pretty sure of what you're getting.

And, I'd opt for quality too [often you do get what you pay for], but several people have been very pleased with incredibly reasonably priced machines.

Have Fun! /forums/images/graemlins/cool.gif

 

[have_blue]

Jason,

You must match the compressor to your needs.

If you intend to use air tools a lot, you better get a good one. Something with ~15cfm @90psi and oil lubricated. Get one with a belt-driven compressor. That usually ends up being one of the largest 120v units available. Tank size is over rated. If you get a good HD compressor, it will run 100% duty cycle, not burn up, and supply enough air while running.

If you will not be using big air tools regularly, then a cheaper unit is fine. The integrated motor "oil less" designs are great for normal home owner duty. The air is cleaner and relitavely moisture free. They are also very inexpensive. The down side is they are noisier than oil lubricated compressors, and will not stand up to continuous use.

I have 4 air compressors. My favorite is a 2hp 8 gallon oil-lubed unit I bought from Harbor Freight for $99. It's not my best compressor, but for $99, I am delighted with it. Of course, all I use it for is to run a die grinder, inflating tires, and occasional air tool use.

 

[EddieWalker]

You really need to say what your price range is.

For a little over $100 you can get a decent portable unit that will handle most weekend projects. They won't take extended abuse or tools with high air demands, but they will run an impact wrench and fill your tires.

Be sure to get one with oil. The "oil less" ones are just a bit cheaper, but don't compare in the quality.

I have two compressors. A small portable cheapy that is great for small stuff and light jobs. It will run my nail gun, grease gun and fill flats. It's a no name brand that I paid around $120 for a few years ago.

My good compressor is an Imglo wheel barrow type. It's an $800 compressor that can handle multiple nailers, my 3/4 impact wrench and run all day without a problem.

It's not up to air sanders or constant supply. For that your looking at several grand.

It gets confusing compairing the ratings. For a first one, I'd say go with a brand your comfortable with.

Eddie

 

[frederic]

You've received excellent advice thus far, regarding models, types, prices, and ratings.

Let me add two things...

First, if you want it to last under a fair amount of use, make sure the pump head is cast iron. A lot of the less costly units are aluminum which is lightweight, but aluminum doesn't stand up to dry scraping from the piston very long. Some of them have cast iron sleeves, which is better, but they can work loose and eventually leak, depending on the design.

A year ago I purchased a used "Quincy" made in the late 50's or early 60's. It's an enormous horizontal unit which fits under the enclosed stairwell in my garage - so it's out of sight. It's a 150 gallon tank if I remember correctly. I paid $350 for it with a bad 3-phase motor, which I replaced with a 3HP Baldor single phase, 220V motor, which I got on ebay for about $50 plus about that in shipping. I had to drill out the shaft hole on the pulley for the larger motor spindle, and then cross-drill through the pulley and the motor shaft to put a pin in, as the set screw on the pulley was stripped and I was too cheap to buy a new pulley. So they've been pinned with 4340N small round stock I had lying around. Well, its a 1/4" pin /forums/images/graemlins/laugh.gif

Second, one of the things I've always liked about Quincy compressors aside from their durability, is their low noise factor. Because they run at a much lower RPM than consumer grade compessors, when they kick in you hear "pfssssst" of the pressure switch chamber, then "putt putt putt putt putt". You can work standing next to one without getting a headache. Mine's in an under-stair closet as I said, so I can barely hear it. I plumbed "black pipe" down the center of the two garage bays with quick disconnects so I can tap in with short, very flexible coily air hoses for workbench use, and under my workbench I have a self-retracting 100' spool of stiffer air hose which I can yank and extend into the driveway for outside work.

I also bought a 5 gallon, dual tank chinese "workman" air compressor for $89 at an auto store, for air "to go" in case I'm helping a friend build something that's not in my driveway. While not a really good compressor and it often doesn't keep up, it is small and reasonably lightweight that I can take it with me.

Before you buy, at least see if you can find an old commercial compressor. Most of them can be rebuilt if they leak for not so much money. A little cylinder honing and a new ring is often all they need, if anything.

 

[Soundguy]

Get plenty of air. i'd guess you don't want anything under 5hp/60 gallon. That's a nice unit for a shop that uses air tools.. etc.

Soundguy

 

[have_blue]

</font><font color="blue" class="small">( I paid $350 for it with a bad 3-phase motor, which I replaced with a 3HP Baldor single phase, 220V motor, )</font>

If you can find a deal like that one, throw all advice out the window and go for it! That compressor will drive brads, run a sander, or anything in between.

Deals like that never find me. That's why I buy cheap stuff and use it until a deal like yours comes along. I'm still waiting.
/forums/images/graemlins/mad.gif

 

[DTCOOPER]

I just sold a 5Hp 60 Gallong Quincy vertical unit with about 200 hours on it, for 662.00 on Ebay. Awesome deal on one of the few American Made compressors left. It is valued at about 1400 bucks. And I shipped it for that 662.00 too ! /forums/images/graemlins/grin.gif

Thanks as always,
Daniel

 

[JasonL]

Thanks Everyone! First I have been reading previous threads as suggested. Second, I am looking for a large shop compressor to put in my new (hopefully soon) shop. I am in the construction trade and have several contractor compressors (Emglo-wheelbarrow- for framing,
Emglo-twin tank- for finish work) I also have a small Porter Cable oilless in my current woodshop. What I think I want is a large compressor I can plumb in a new shop. I am planning to build a woodshop in the basement with a structural concrete slab above so I can have a tractor/truck workshop on the main level. It looks like some of the really nice compressors might set me back several thousand!? Don't know if I can justify that until I at least get the shop built. I suppose I could just use what I have now and still plumb them in untill I can afford a nice one. Thanks, Jason

 

[LetsRoll]

Watch out for Napa cause they have a Farm/Auto sale from time to time (well they do here). You don't have to pay shipping and if your good, you might be able to talk them down even lower than what there sales are going for. But, if you don't have the funds on hand at the time, the Napa here will lease you the unit. And the last payment will be a $1, which will pay for the compressor. I just opt to pay for the compressor since I had the money and was ready to buy. They also gave me a one year warranty on the compressor. The link below is the compressor I purchased from Napa. I talked the owner down to $1608 and some change. I haven't had a problem with it and the noise level is not that bad. I used it once for 4 hours sandblasting and the only problem I had was the meter on the house was going crazy. This compressor pulls 60 amps (30 amps per leg). Other than the amount of amps it takes to run this unit, I've been pleased with this unit. And "if" I have a problem, my local Napa can get me the parts for it.

http://www.napaonline.com/cgi-bin/ncommerce3/ExecMacro/NAPAonline/search_results_product_detail.d2w/report?prrfnbr=15627876&prmenbr=5806&usrcommgrpid=

Attributes: Air Compressor
Gas or Electric: Electric
Stage Type: Dual Stage
Horsepower: 5 HP
SCFM Rating: 16
Maximum Pressure: 175 psi
Pump RPM: 800
Phase & Voltage: 1Phase, 230v
Motor Type: Baldor
# of Cylinders: 2
Pump Material: Cast Iron
Type: Reciprocating
Series: Professional
Magnetic Starter Included: No (Napa said it's included)
Magnetic Starter Required: Yes
Lubrication System Type: Splash
Tank Type: Horizontal
Tank Capacity: 80 gal
Height: 53''
Length: 71''
Width: 31''
Weight: 580 lbs
CFM Pump Displacement: 21.7

~Note~
I included the stats cause I can't get the link to come back up for me.

 

[frederic]

</font><font color="blueclass=small">( Deals like that never find me. That's why I buy cheap stuff and use it until a deal like yours comes along. I'm still waiting. /forums/images/graemlins/mad.gif )</font>

Well, truth be told, before I bought that unit I was about to buy a 80 gallon Husky (home depot) vertical unit, because I have so many home depot gift cards (my family and friends apparently aren't very creative), and putting all the cards together essentially made the compressor free. Then a friend of mine who I respect sold me on the same story I shared here, and I spent eight months or so suffering with my portable, toy compressor (trying to sandblast, run my plasma cutter, etc) trying to find the right deal. I had set a virtual dollar amount of $500 for a non-working unit in non-leaking condition, and $850 for a working unit, plug and play. Took a long time to find, and as impatient as I tend to be I'm really glad I waited. While there isn't anything wrong with the home depot unit, I have to say the quincy and equivilent commercial machines are awesome.

With my plasma cutter, I can cut 1/2" plate and never have to stop waiting for the air compressor to keep up. With my toy compressor plumbed in, I'd cut about two inches into 1/8" plate and the plasma cutter would shut off, waiting for more air to become available. Even with an adjustable regulator.

Even if you play with "toy air tools" there is no such thing as too much air.

My cousin came over with his rusty clunker earlier in the summer, and he was air-sanding rust off one side, while I was air-sheering off panels on the other.

 

[Spiffy]

I wouldn't mind having one of those true industrial units either; especially if I ever find a deal like Frederic did.

Since you have the Emglo units; it might be of interest that "Steam Jenny" bought the real Emglo line [as opposed to the imported knock offs] and I wouldn't doubt they make a bullet-proof unit. Of course, you'd probably pay for it too, but you never know.

Anyway, you can still get a lot of compressor under 2K delivered or even less:

Starting low: another member said he was happy runnning even a blaster on a sub $500 Puma?; I think about the same thing as the "iron horse" at Runnings [I'd still get around 20CFM - output, not displacement; I think about $900 in that line] . The IRs I seen at TSC looked a little nicer, but were built much the same [I do recall, they had a $1500 IR that looked pretty heavy].

Going further, it probaly won't be quite the bullet proof machine as Frederic's industrial one, but I wouldn't be too afraid of Quincy or Champion "heavy duty consumer" units...the reed valves [like all the aforementioned units] are a "red flag" but since we're not talking mission critical, they are the essence of simplicity: either they work or they're broke [not sure if I ever heard of one sticking or leaking etc.]. In retrospect, I would have even considered this route and just had replacement set on hand...though they'd likely never fail in my life anyway. I'm guessing the Napa one may fit this list or probably about like the IR's I mentioned.

Quincy @ TP Tools


For exactly 2K (I've never tried haggling with TP, but maybe you'd get delivery thrown in) the Champion Advantage looks like a die hard....disk valves...tapered roller bearings...arrhhh arrhhhh arrhhhhh! Not sure about buying "big ticket" things on Ebay, but I think the same unit is listed for $1885 w/ free shipping.

Champion

Irronically, you listed in build it yourself. I had a 60 gallon horizontal tank; so I bought an Eaton 2Stage 20CFM and a industrial 5HP. The head unloaders [the motor stays running under no load, while air just blows in and out of the intakes helping cool it] are an awesome feature I'd recommend for any high consumption application. I releazed just a little late that Eaton sells imported pumps; the "fit and finish" left much to be desired; but Eaton was exactly right about their heavy duty design, very knowledgable, and I still like they way advertise true HP....so, I would have still liked a domestic pump [including reasons beyond the product itself], else, I don't have regrets.

While you're plumbing, don't forget to use plenty of black pipe and slope it for water knock-out....Filter-Regulators or F-R-Lubricators are invaluable too....just don't oil any branchs that won't be used exclusively for air wrenches and the like. Blasters and paint guns benefit from a coalescing filter too [and I really like a desicant right before the paint gun too]. /forums/images/graemlins/cool.gif

 

[frederic]

In the spirit of DIY, find yourself a junkyard 3-cylinder Geo Metro engine, rehone the cylinders, replace the rings, and make an adaptor from the crankshaft tail (where the flywheel used to be) and splice in a 5HP 220V Beldar motor. Then fill the crankcase with oil, make a plate to seal the three exhaust ports, then insert threaded bungs into the spark plug holes, then combine them in a small "manifold" made of a piece of black pipe, put a large 1" check valve on the end of that, then feed your air tubing throughout your garage from that check valve.

Believe it or not, some of us "old guys" remember when Popular Mechanics had an article on a special camshaft that converted an air-cooled VW engine to a two-cylinder gas engine, using the remaining two cylinders to compress air into a tank of your choosing /forums/images/graemlins/laugh.gif

 

[40Kchicks]

This year I put 3 waste oil heaters in my barns because propane is getting so expensive. Each heater uses 3cfm plus I have a small air operated diaphragm pump that pumps oil to heaters. I looked around and found the Home Depot Husky 80 gal 2 stage compressor gave me about the best bang for the buck. I wanted an air compressor that would last and have low RPM’s and thus low noise. The Husky unit is pretty good. It isn’t as high of flow as some but then at 17.5amps it’s not as power hungry either. It has more of a putt, putt, putt sound to it which I like. The compressor is rated for 10,000 hours. I would recommend it.

Eric

 

[RalphVa]

I've a Clark Champ bought at TSC for less than $200. It's an oil type with quality parts, like the copper drain valve. Think it's 5.0 SCFM.

I've used it for tires, driving my Farmhand 550 ft-lb air impact wrench, powering my Farmhand touchup sprayer and for blowing off the tractor. It's the best compressor I've ever had, lots better than a couple of oilless ones that usually quit after a bit.

Ralph