Learn me air compressors

I did a quick search and people just say to buy the biggest you can afford. Well, I haven't set a budget and am looking to see how much it would cost me to get a compressor that does what I need to do.

The immediate use is to pump up tires and to rebuild brake calipers. I would also like to run an impact wrench, air ratchet and air hammer. Just for general auto DIY stuff. Not sure what CFM and capacity I need.

I'm looking at a Harbor Freight compressor right now. For $150, it seems pretty good. Compressor link. What do you guys say about it?

^I'm looking into the same thing.

I bought the biggest I could afford - a more industrial unit by DeVair. I do run a machine shop at my house though and CNC mills need a constant supply for tool changes. This one - Devair 5052

Aside from the shop, I just use mine for blowing up tires for now, as I haven't bought any other air tools. I wanted capacity enough to eventually add a sandblaster, etc...

I didn't pay anywhere near the $3k or so listed for it as I got lucky and found it one town over where a woodworking shop was closing down. So I'd suggest looking around for a more upscale used one if possible. Look around for what accessories you want to add on and make sure whatever you buy can support the CFM requirements.

You can also take a look at this conversation: Garage Journal

Good luck,

Sean

The HF one should run the occasional impact gun and air your tires up. Air ratchet shouldn't be a problem. Too light for painting, bead blasting or DA Sanding. Too small for any serious cut off tool work. For a bill and a half, it's not bad.

If you can use a 220V unit then get one that can run on it. Also try to compare CFM ratings, both @40PSI and @90 PSI. Those are the two pressures that most compressors are rated at. 40 PSI is for painting and 90 psi is for air tools, blasting, etc. I like to see at least 10 CFM at 90 PSI or higher. I don't do much painting so I don't look at the 40 PSI rating but if the 90 PSI rating is high enough then the 40 PSI rating will take care of it's self. Also look at the size of the tank. I think that 20 Gal. is minimum.

Just like any consumer grade power tools, you can either take your chances with new imported stuff, or for the same money, buy used pro grade USA built stuff that was made to last forever, or for cheaper do the former and some tinkering. This is how I'm getting a pro grade 12" benchtop drill press for $100, I bought a 1940s craftsman off CL for $50 and I'm going through it.

If you have time, start searching craigslists for however far you're willing to drive to buy a compressor you'll have forever, for cheap. I went through a succession of cheap "oilless" units. They infuriate you, use a ton of power, are deafening, and last about 2-3 years max. I finally found, after a year of looking, a like-new Grainger Speedaire 60 gallon, 5hp, 2-stage, 4 cylinder, 230v, single phase, American made air-compressing monster.

I bought it and an equally nice Millermatic 185 MIG welder w/ an 80cu/ft C25 bottle and a fresh giant spool of .030 wire for $800 the pair. New they'd have been like $3400.

The big green Speedaire will do close to 17 cfm at 90psi, and while my blast cabinet w/ a big tip will give it a workout, w/ regular air tools it periodically refills in about a minute, and it makes a lovely reassuring chugga-chugga-chugga sound.

Please try to wait and buy a good one.

The HF one you are looking at isn't bad. I use the same one at my office for tires and to run the occasional impact or air ratchet. A 1/2" impact will drain the tank in a hurry, but for limited use it will work.

For my shop I use a 80 gal Quincy. It will keep up with anything I do.

I started out with a 20 gallon, up-right, oiless, Crapsman, POS. It mostly did what I needed, LOUDLY, and often slowly, if I had it to do again, I would NOT buy that compressor. In fact, I'd just as soon never have an oiless compressor as my only/primary compressor again.

After the Crapsman burned up (common issue on the model I had) I bought a used Speedaire (Grainger house brand) 20 gallon, horizontal, oiled, single stage, twin cylinder, compressor that had sat in front of a local pawn shop for months. It was neglected and in disrepair. It had 1/4" of dirt on top of the pistons from being ran without a filter. It wouldn't pressurize past 40 PSI at the pawn shop, and I talked them into letting it go for $30. I bought a ring kit from Grainger, spent a little time with a hone, cleaned everything, put a new unloader valve on it, used the pressure switch from the dead Crapsman, and had a decent compressor for less than $100.

I still have the Speedaire, but it was limited in capacity, and a few months after rebuilding it, it developed a big issue, either I screwed something up, I tend to do that, or got a bad part when I rebuilt it, I found out a several years later, when I finally investigated, that one of the new rings I put in it was broken, it caused oil blow-by worse than anything I have ever seen, and would quickly fill the water/oil trap on my regulator. This made the compressor fairly useless for painting, or much else for that matter, and I eventually got frustrated to the point that I said screw it I'm getting a new compressor, and I'm getting a REAL compressor.

I had a $500 budget, and went on the hunt for a NEW, large capacity (50+ gallons), air compressor. After comparing all of the options on the market at the time I decided on the Kobalt 60 gallon compressor from Lowe's. It was near the top of my budget, but inched out it's competition in most categories, 155 PSI where most are 150 or less, a couple more CFM @ 90 PSI than most others, and with a Lowe's card you got 0% interest for 6 months. I still feel that for a single stage, home shop use compressor, for the price the Kobalt is the one to get. Only downside is it's 220V, and it takes up some floor space. Kobalt 3.7-HP 60-Gallon 155-PSI Air Compressor

So as the evolution of my compressor ownership continued, I moved to a 1 car garage townhouse in Ohio, the Kobalt got moved to my parent's barn, and I took the Speedaire and a Porter Cable pancake compressor with me. I used that pancake compressor A LOT, it's oiless, so LOUD, tiny capacity, so it cycles often, near constant when using the impact a lot, but it worked in a pinch.

I finally got to the end of my rope with the pancake, and decided to tare the Speedaire apart again, discovered the broken piston ring, put new rings on it again, and started using it again.

We eventually left OH, and have been back home for about 6 months now. My Kobalt is still in dad's barn, I still have the Speedaire and the pancake as my go to compressors.

I needed to add air to my tires last week, the Speedaire was empty, so to save time I grabbed the Porter Cable pancake.

If we weren't in a rental and/or the breaker box wasn't outside on the other end of the house, I'd have 220V wired in the garage, and my Kobalt would be in my garage closet.

Cliff's Notes: Don't buy an oiless, buy the largest capacity, highest CFM you can afford/have room for, I like the Kobalt 60 gallon compressor from Lowe's.

• Lee

I own two compressors. One is a Craftsman 25 gallon, 2 hp belt-driven compressor. The other is a Campbell Hausfeld upright, oilless compressor, direct drive, and I think its a 2 hp, 40 gallon.

Both have worked well for me for a decade of abuse. I expect the CH oilless to seize up any day. The bearings are squeaking, the piston isn't sealing well because the tank takes forever to fill up. I expect the Craftsman to give me another 40 years, at which point it will develop a pinhole leak in the tank and I'll have to scavenge the compressor and motor to put on another tank and use it for another 40 years.

Plus, when the Craftsman kicks on it sounds like a cute little ticking pump. When the CH kicks on it sounds like the apocalypse and gives me a heart attack.

A good, belt-driven, oiled pump is usually a much better performer, a lot more long-lived, and so much quieter for not crazy money.

One variable not discussed is portability. Do you need it to move easily? If so, the HF one will do OK for the things you identified. I had a similar oil less Black Max that followed me around for nearly 30 years that did most everything I needed-- mostly air tools and tire inflation. I used it to paint the occasional fender or house shutters, as well. I also used a cutoff wheel with it, but only for smaller jobs. I finally sold it and bought a 60 gallon Puma upright recently, largely because I also bought a blast cabinet. I also have a cheap pancake compressor that goes to the track with me.

I've had a Craftsman 33 gallon oiless compressor for the last 5 years. It served me well to run drill motor, impact wrench, die grinder if not used continuous. It could not keep up with a dual action sander or a small sand blast cabinet. Biggest complaint was it was really load while running and that was a good amount of the time working. When I say load I mean having to turn it off to talk if someone came into the shop. Nothing will drowned out the noise.

For the last year it was running on borrowed time and taking a long time to fill the tank. I have just replaced it with a Lowes Kobalt 60 gallon(Cambell Hausfield)single stage two cylinder. A two stage would have been what I wanted but just couldn't justify the cost which would have been double plus. If you want to do much sand blasting you will need a bigger comprssor unless you are will to blast and wait. If you want a small portable compressor I would at least get a belt driven oil lubricated single or two cylinder to cut back on the noise and also for the longevity. r

Alright, so the suggestions are still buy the biggest you can afford.

Reading around, it seems that I should look at CFM @ 90 PSI (pressure air tools are run at) and then tank capacity. I'm seeing that 10+ CFM would be ideal, but that is in the $300 range for new compressors. Belt driven oiled compressors are much quieter and will last longer.

I'll keep searching CL for a nice used one that pops up this summer then.

MINIzguy wrote: I did a quick search and people just say to buy the biggest you can afford. Well, I haven't set a budget and am looking to see how much it would cost me to get a compressor that does what I need to do. The immediate use is to pump up tires and to rebuild brake calipers. I would also like to run an impact wrench, air ratchet and air hammer. Just for general auto DIY stuff. Not sure what CFM and capacity I need. I'm looking at a Harbor Freight compressor right now. For $150, it seems pretty good. Compressor link. What do you guys say about it?

I have that one. It's fine for small stuff (rebuilding brake calipers, airing up tires, filling my race tank, etc). With a 3/8 air ratchet it kicks on pretty quick - after 4 or 5 bolts. I tried an air impact and it literally couldn't keep up with the air usage. HF air tools actually say the "suggested" size for them....only the very small tools suggest under 30 gallon tanks or so.

I have mine because it was free, but once I have some cash I plan to go with a larger tank......

I will say that it is oiled, and it isn't all that loud, and it's been dead-nuts reliable, even after it sat out in a farm field in the weather for 2 years :)

I had a Sanborn 5hp, single-stage, 60 gal. tank, 50% duty cycle, 220V for over 20 years that sounds similar to the Kobalt mentioned earlier. It easily aired tires, ran impacts, ratchets and small die grinders w/o cycling too often. That was great for general shop use. OTOH, sanders, grinders, blasting and other air hogs you just had to wait... the 50% duty cycle thing.

I sold it on CL for $180 and it was still a great compressor, easy maintenance w/ filters and oil changes, still had the original belts and pump. Keep the tank drained of condensation, they will collect a lotta moisture. Haven't looked in a while but there may be some good deals on CL.

I replaced it w/ a 5hp two-stage I-R, 100% duty cycle, should be the last compressor I buy but costs a lot more than you wanna spend.

I'm in the same boat myself after I just picked this one up this week from Harbor Freight:

21 Gallon HF Upright Air Compressor

I will say that I spent about 3 days researching what was available from the average big box hardware stores and I came to the conclusion that as much as I normally look at Harbor Freight tools with a bit of apprehension and skepticism, they had 207 mostly positive reviews for this one and it was the best I was going to get with a $200-$300 budget on short notice without driving all over the damn countryside to find a good deal on a more robust, used, quality air compressor. Besides that, many of the ones I saw for sale on CL seemed to be gigantic and out of the scope of my needs and budget.

Like everyone has already said I also came to the conclusion that you want to avoid oiless because they burn out earlier and they are ungodly loud. I couldn't find an oiled compressor for less then I did for the 21 gallon HF one I bought.

I'm going to break it in and drain the oil and replace it tomorrow and I'll probably be putting it to good use this weekend so I can hop back on later and give you a good review.

This HF compressor would be more suitable if you have the room. Same motor but twice the tank size for $20 more.

ross2004 wrote: [This](http://www.harborfreight.com/air-tools/air-compressors/25-horsepower-21-gal-125-psi-cast-iron-vertical-air-compressor-67847.html) HF compressor would be more suitable if you have the room. Same motor but twice the tank size for $20 more.

After living with a horizontal 20 gallon compressor, I'd definitely consider a vertical a big plus. Smaller footprint that you wouldn't trip over as much and easier to move around. That alone would be worth an extra $20 to me.

In reply to bigdaddylee82:

I've been looking at the same $500 Kobalt compressor, or maybe even the next one up. I can easily run a 230V line from my panel and my plan would be to install the compressor in my basement and run piping into my garage. My garage is small and I want the floor space.

Personally, I have a Craftsman oil-less compressor similar to the H-F OP. It's worked well enough for 20+ years, but it has trouble keeping up with my IR2135ti when doing serious impact work (like removing axle nuts, or the 8 lug nuts on my old truck) and it really has trouble running my cut-off wheel or air-ratchet (which can be surprising air-hogs). It's also mudder-berking loud.

I picked up an upright, 20gal compressor from Costco for $170. It's branded as a snap-on, though I'd bet money that it's made in China. Model #691915. It was the floor model so I haggled them down a little bit, I think they regularly sell for $200. It's loud and a bit underpowered, but tough to beat for the price.

I just picked up similar one from lowes depot -125 psi for the same price. Works well for a floor nailer and tires. Noisy for an oiler. For any serious shop work my advice is hunt down a 2-stage compressor with a decent cfm.

In reply to Ian F:

I still have the list I had narrowed it down to at the time, prices/models may not be accurate this was from about 5 years ago:

Husky 60 Gal 10.2 CFM @ 90 PSI $375 (Refurbished & Online Only, but free shipping)

Kobalt 60 Gal 11.5 CFM @ 90 PSI $439

I had just about made my mind up on the CH from TSC, then someone mentioned the Kobalt to me, I'm glad they did.

• Lee

In reply to Ian F:

It also fits in the back of a Jeep Wrangler with the rear seat removed.

At the time I got mine you could still get the 10% off Lowe's coupon with the change of address packets from the Post Office.

• Lee

ross2004 wrote: [This](http://www.harborfreight.com/air-tools/air-compressors/25-horsepower-21-gal-125-psi-cast-iron-vertical-air-compressor-67847.html) HF compressor would be more suitable if you have the room. Same motor but twice the tank size for $20 more.

Thats still not the HF compressor you want. This is http://www.harborfreight.com/air-tools/air-compressors/2-horsepower-29-gal-150-cast-iron-vertical-air-compressor-68127.html The ones that arent belt driven all blow dick. Alternatively you can try buying a compressor on craigslist with a blown compressor and putting one of the HF compressor units on the tank.

No doubt that's a better compressor, but it's also $265 more expensive (if having it shipped). I have the 21 gal/2.5 HP unit and it's done everything I've asked of it: air chisel, impact wrench, air ratchet, paint sprayer, tires, sweat evaoporator. It's loud, but after a years use building a Lemons car I'd buy it again in a second.