how much compressor...

[mhm993]

How much compressor do I need?

We're waiting to get the c of o for our new 600 sq ft garage. It's a small garage, squeezing in 2 bays, a lift, loft, and a shop area. I do basic wrenching- change pads and rotors, belts and filters kind of repairs. I guess I'll buy a half inch impact wrench and some assorted other basic air tools. It also needs to run my 4 post lift and rolling jack. I expect to turn it on a couple times week but it's never getting constant use and I'm not learning body work. Maybe build a deck and buy a nail gun, too. The garage is not going to be heated, and I have 110 and 220. I'll put up 1/2" black pipe for air lines.

Putting our natural bigger is better creed aside, how much compressor do I really need? I assume I'll spend enough $$ to get an oil lubricated pump. Can I get away with a 5.5cfm at 90 machine? How about tank size--I see good contractor quality 20 gallon horizontal compressors on deep discount sometimes. Do I have any realistic reason to need 40 gallons or even 60?


Anyway, you all get what I mean. How much is too much? And how much is too little?

 

[russlaferrera]

IMO you can use a 1-2 hp, 10 gallon compressor. It will run an impact wrench, nail gun, blow gun, fill up the kids bicycle tire. IF that's all you want to do great.

DO NOT expect to use any other air tools for any period of time. Remember there is a lot of air tools out there.

 

[wrigh003]

I like my 25-gallon Craftsman Pro horizontal one. It's $400, if you wait you will find a 20% off all air tools sale or something and can snag it for $320, which is what I did. It's big enough for anything I'll need it for (requirements same as yours), and semi-portable (It does have wheels, hope you're not toting it too far, though) to boot.

Plus, it's pretty quiet.
http://www.sears.com/shc/s/p_10153_...&+Air+Tools&sName=Air+Compressors+&+Inflators

 

[wantedabiggergarage]

The compressor we have at the shop, has to be able to operate two lifts, and air tools. You need the requirements of your tools, to properly figure current consumption, then plan for a little more.

 

[sharpshooter]

You can never go to big.... look at the model you can afford, then get the next model up

 

[Maulerman]

1.5-2HP should be plenty for an impact wrench. It has a low duty cycle. Most mechanics tools have a similar low duty cycle. If your doing body work that's another story.
My neighbor's son once strolled by my garage and saw my 2HP compressor and thought it was huge so I grabbed my photo album and showed him the 500HP recip I sold a local foundry. Now that's a big compressor! He was floored.

 

[malibu101]

I am a weekend wrencher. I don't run my compressor hard everyday either. Yeah, impacts low duty cycle will run quite well on a smaller compressor.
Die grinders and cutoff wheels are a natural step when you have air but they take quite a bit of air. A "small" compresor will frustrate you if you buy some other tools.

 

[mhm993]

So, if we still assume I'm not going to do body work,that I won't be using more than one tool at a time, but I want some excess capacity anyway, is it more important to have extra capacity in cfm or extra capacity in the size of the tank?

My current choices are:
1-box store 40 gallon at 5.5cfm--maybe 1.5-2 hp.
2-industrial brand 20 gallon at 9cfm ( 3 hp @220v) for a little more $ than #1 --3hp
3-industrial brand 20 gallon at 5.5cfm (2hp @110/220) at extremely deep discount.

#3 is stupid cheap--I'm thinking I should probably buy anyway but I dunno.
(alternatively, I can blow the budget and get an IR model from northern freight w/ 60 gallons and lots of cfm)

Any helpful thoughts? One other question--are speedaire/dayton compressors made in usa or china?

 

[Matti]

You might want to hear some of the less expensive direct drive compressors run before buying one. I hear some of them really scream. I bought a 5 hp Campbell Hausfeld belt drive unit with a 20 gallon tank. It's not really 5 hp because you can't run that one 110v! It is okay but will not run a DA sander continuously. I believe it is about 6 - 9 cfm. For bodywork you need a real 5 hp 220V unit which will put out about 18 cfm.

 

[goodfellow]

It's a matter of convenience. Years ago when I didn't have a garage and had to move my equipment in and out of the house on a regular basis, I bought a nice SEARS 2HP, belt driven 20 gal unit that ran on 220v. It was a great compressor and ran all my impact tools well. I also sanded, primed and painted three cars cars with it. That was frustrating, but I managed.

1/2" Impact tools and high speed grinders ate up the CFM and made it run contiunuously at times. Paint guns, pressure sprayers and high volume air blow guns will do the same.

If you're a patient type of guy, then a smaller 20-30 gal unit will work just fine. Just stay away from the direct drive units.

Many of us are spoiled by BIG AIR, but I know a few "old timer" gearheads with great hobby shops who produced fantastic looking cars with just a small standard 12 or 20 gal. 1HP SEARS or WARDS compressor as their only source of air.

 

[SteveU]

Once you get a compressor you will continue to find new uses/tools for it that you wouldn't have imagined before you had one. Something like this will run anything a home shop will throw at it but will run around 1300.00 shipped. What type of budget you have is a big factor but my recommendation is to get the largest one you can afford because you will NEVER regret having too much air but WILL regret too small of a machine everytime you have to wait for it or when you find it won't do what you want.

 

[mhm993]

nice setup, steve.

 

[goodfellow]

Beautiful -- nice looking machine. Mind sharing the specs Steve?

 

[SteveU]

Beautiful -- nice looking machine. Mind sharing the specs Steve?

It is the 5 hp 2 cyl single stage Eaton which has a 32 cfm pump running at 650 rpm and according to their website does 19.5 cfm @ 100 psi. It is quiet enough to have a conversation standing 5' away from it while it's running without raising your voice, the sound reminds me of an old farm tractor. Both the motor & pump are much larger than anything you will find in a big box store. Others prefer a 2 stage but this will run a 3/4" impact no problem along with any other air tool I've hooked to it so to me this is more than enough and don't see where a 2 stage would have been an improvement.