NFB: Choosing an air compressor

[Benm109]

Well, I think it's finally time that I break down and buy an air compressor. It's getting to the point where I'm working on all of my family's and friends cars, but not having any air tools is holding me back from certain jobs.

Anyway, I've been doing a lot of searching, price comparing, etc., and I'm still pretty much clueless as to what I really need. My only requirements are that it is portable and can operate a 1/2 impact wrench continuously (at least be able to remove lug nuts without having to wait). I'm pretty much faithful to Craftsman, but I'll consider any recommendations.

I think that this compressor is what I'm looking for, but I'm not totally sure. It's a 15 gallon, 3 HP, and 150 PSI max. working pressure vertical air compressor. It even comes with an accessory kiy and 3/8" ratchet. Here's a link to it: http://www.sears.com/sr/javasr/produ...id=00916644000

So basically, does anyone have any suggestions, advice, or recommendations for a decent air compressor? Is the one I've selected any good? I'm open to anything right now.

[Coop '02Z]

I forgot the name for them, but the one you are looking at will be REALLY loud, it is the direct drive type and the way the compressor portion works makes it louder. There is another type that has the motor separate (6 or 8 inches away) from the compressor and it drives the compressor with a belt and pulley.

like this:


Hope this helps

[Injuneer]

You need to consider your power availability.... 120V or 220V.

Portability is a nebulus concept.... I have a 30gal vertical tank unit like the one posted above, but its got wheels and a handle on it. Is it "portable"? Only if you never have to lift it.

I would definitely go as high as you can on pressure. My Craftsman is probably 6 or 7 years old and is a 125psi unit. I think they have upgraded the newer units to 150 or 175psi. It runs on 120V, but needs a 20-amp circuit, rather than the common 15-amp household circuit. Its a 6HP oil free..... probably not "professional grade".... but has proven to be adequate for making quick work of a spring compressor using an air ratchet.

[Steel2686]

I'm a carpenter, and I use a Campbell Hausfeld twin-stack portable. We run three to four trim nailers continuously on it with little to no . I've used my impact wrench on it before with no issues of either.

The pancake style compressors are nice, but don't hold near as much air. The twin-stacks are the way to go for more cfm's, yet still remain portable.

[Performin Norman]

I'm shopping for a new one also. I want one that is super quiet.

[Steel2686]

I'm shopping for a new one also. I want one that is super quiet.

Then Campbell Hausfeld is out of the question. I don't know what it is about them, but it's like they put an amplifier on the motor. They are the loudest compressors out there.

[Benm109]

You need to consider your power availability.... 120V or 220V.

I knew I'd forget some details . 120V is all I have to work with in my garage. Noise is not really a concern, either .

Portability is a nebulus concept.... I have a 30gal vertical tank unit like the one posted above, but its got wheels and a handle on it. Is it "portable"? Only if you never have to lift it.

I guess I should've explained it a little more. I think what I meant by portable was to be able to put the compressor in the back of my Camaro and drive to a family member or friend's house and use it there, if I ever have to.


I really appreciate all of the replies so far.

[bru333]

I'm shopping for a new one also. I want one that is super quiet.

Then you want one that has oil lubrication for the pump. The oil free ones are extremly noisy. If you aren't planing on having it portable you can build an vented enclosure around it to cut the noise even more.

If you don't want to wait 3.5 scfm is a little low. I wouldn't go less than 5 CFM. Get the highest pressure and CFM (CFM being more important) that you can. All my tools at work are 4.5 CFM and up, things like a die grinder or sander use the most air (6-12 cfm), impact wrenchs and air ratchets are 4-6 CFM.
Most air tools will run at 90 psi, but you can bump them up for removal of more stubbon fasteners. Our shop air at work is set at 90psi (oops...how did my hoses get turned up to 110 psi?), with some special tools reduced to lower pressures.

[Jeff_in_Atl]

You need to see how much volume of air the tool you want to use uses. Make sure the compressor is capable of that volume. Nail guns don't use that much volume. Ratchets can use a lot.

edit/add what Bru333 said

[Jeff_in_Atl]

I'm shopping for a new one also. I want one that is super quiet.

Norm get a screw compressor. Way more quiet. You do have to watch out for them freezing in the winter though. We had to put a space heater in our compressor room here in Georgia because ours froze. It's huge too.

[Benm109]

Thanks everyone, I think I'm finally close to choosing the right air compressor. I'm going to Sears tonight to look and see what they have, and hopefully find an employee with some air compressor knowledge, and see what they have to say, as well. Once again, I really appreciate all the help with this.

[WICKED LT1]

Then you want one that has oil lubrication for the pump. The oil free ones are extremly noisy. If you aren't planing on having it portable you can build an vented enclosure around it to cut the noise even more.

If you don't want to wait 3.5 scfm is a little low. I wouldn't go less than 5 CFM. Get the highest pressure and CFM (CFM being more important) that you can. All my tools at work are 4.5 CFM and up, things like a die grinder or sander use the most air (6-12 cfm), impact wrenchs and air ratchets are 4-6 CFM.
Most air tools will run at 90 psi, but you can bump them up for removal of more stubbon fasteners. Our shop air at work is set at 90psi (oops...how did my hoses get turned up to 110 psi?), with some special tools reduced to lower pressures.

Good Info ^

Keep in mind that most compressors are dual rated. CFM @ 90PSI and CFM@45PSI. Do not get confused by the Sears dude. Most auto air tools run at 90 PSI and will need 5 CFM or better. I got a Craftsman that runs at 5.6 CFM @ 90PSI and I think that is the minimum I would go with. It is a vertical 6HP 30 Gallon. CFM means how hard it can drive, Volume of the tank is how long it can go before running the motor again. If you are thinking of sanding or running tools for long periods you should look into a 220V with a bigger tank. If your use is mainly bursty auto tools, then the above mentioned is probably ok. HTH


-Paul

[Benm109]

I just have one more question . I have been looking through catalogs and looking at the all the accessories. I noticed that they have air tool oilers and filters. Are these worth having, or not? Or, a better question, are there any accessories I should buy after getting an air compressor? I know the air tool oiler isn't really necessary, and I already have the habit of oiling air tools before I use them, but what's the purpose of the filter?

[Injuneer]

You need an oiler for most tools. I bought a little inline unit that you fill with oil, and screwed it into a flex joint. Then put male and female quick connects on the flex joint/oiler combo. That way, I only have the oiler on the line when I'm using a tool than needs it. It can be left off when you are filling tires, etc.

[SteveH95Formula]

I just have one more question . I have been looking through catalogs and looking at the all the accessories. I noticed that they have air tool oilers and filters. Are these worth having, or not? Or, a better question, are there any accessories I should buy after getting an air compressor? I know the air tool oiler isn't really necessary, and I already have the habit of oiling air tools before I use them, but what's the purpose of the filter?

I'd get an air/water seperator that traps water from rusting your tools. Either a filter or a trap that you can drain. If you do not paint you can put in an oiler but you are probably fine without one. At least get a water trap. Most compressors have regualtors so you should be ok there. If you are painting I'd get a regulator that by the gun and a water/particle filter. An oiler of coasre would not be a good idea unless you can at least turn it off if you are going to paint.