help in compresser size

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silver fox

silver fox

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i need a comp. i'm starting the boby work on the duster this spring i'd like to know what size to get it's not to paint but would like to run some air tool's and prime . What should i look for, i'd like something i can move around for ex. part store here has a 8 gal. plus air gun & rachet ect. on wheel's for $ 199. would it do, i know buy cheap get cheap or should i look for something bigger if i talk to a sales person he'll say bigger for buck's but i'll talk to the one's who really use thank's for your input
 
Hey if your using a sandblaster u need something wit 23 + cfm, if your just using air tools u can get away with 11-12 cfm... i work at Bodywork myself and sell compressors at Napa autoparts..
 
Small compressors can't keep up so they run and run and run which is not only noisy (unless it's an old speedair or something like that) but they also generate a ton of condensation which comes out of your tools. Tools that spin, like a die ginder for instance suck a ton of cfm. The bigger the better if you can afford it, also bigger means 220 wiring so you have to take that into consideration.

The one I have is 30cfm at 100psi and even that runs more than I like although for painting it's fabulous, barely comes on.
 
Make sure you go by CFM rating at a given PSI...OTHER than zero. A LOT of compressor manufacturers are sneaky and rate their zero PSI to inflate (pun intended) their numbers. I usually like using 90 PSI as a baseline because that will run most air tools. So look for the compressor with the most CFM and biggest tank and HP you can afford at 90 PSI.
 
Yea what he said :) Honestly I wouldn't even bother with a small roll around compressor, they just can't keep up. All tools have a rating on them as well and will show you what they need to run. Also find a compressor with a iron pump and not aluminum if possible.
 
If you are doing bodywork, you will need the CFM, as stated for your D/A. Buy a good one, and it will serve you well.
 
Mine is 5 h.p. 30 gal, I run air tools all the time and primed my Duster with it besides priming and painting my old F250.
 
StrokerScamp said:
Make sure you go by CFM rating at a given PSI...OTHER than zero. A LOT of compressor manufacturers are sneaky and rate their zero PSI to inflate (pun intended) their numbers. I usually like using 90 PSI as a baseline because that will run most air tools. So look for the compressor with the most CFM and biggest tank and HP you can afford at 90 PSI.
Click to expand...

wrjjol.jpg


ABOUT THE GALLONS. The tank size has almost NOTHING to do with a compressor performance. All that means is, that for "short use tools," like impacts, air chisels, etc, you won't need as much HP or CFM because the pump can work in between tool uses.

For "long use" (high duty cycle) tools like sanders, grinders, sand blasters, and PAINT GUNS you don't want to go by "gallons" you want to go by TRUE CFM



ABOUT HORSEPOWER HP like everything else, has become an "enhanced math", "imaginary number." Many HP ratings are based on the amount of power the unit draws off the line and NOT shaft HP. This is a simple way of making a small unit seem big

ABOUT CFM

There are TWO big LIES about CFM

The worst is the rating "at SCFM" This is the "best" way of making a SMALL compressor seem BIG because this is the rating at the atmospheric pressure entering the suction port.

The second worst is "at 40 psi." I believe this was coined by people such as Wards and Sears "back when" because they realized that a "bleeder" air gun and most tire filling really only needed 30-40 PSI, so this makes a "medium" copressor sound "big."

The only REAL rating is rated almost universally "at 90PSI" This figure IF IT IS NOT A LIE is the REAL airflow that your compressor can deliver to real air tools.

You need to pick your biggest tool, or the biggest one you expect to obtain, and buy accordingly

DO NOT ever buy a direct drive compressor. Buy a belt drive

Do not buy an "oiless" compressor

Try to buy one with a cast iron pump, or AT LEAST a cast iron cylinder and head

Even some "brands" that used to be "solid" are now peddling Chineseo junk
 
I have a 5hp and 30 gallon and it can't keep up for any extended period of running. Air tools like impact I can run 2 or 3 lug nuts off and have to wait. It can't begin to keep up with my die grinder.

I'm looking at getting at least a 60 gallon, something along this line with a good air filtration system.

http://www.northerntool.com/shop/tools/product_200318461_200318461
 
Agree with 67Dart273

CFM at 90

Tank size is not a factor. Max psi is really not a factor either.

I have a 32 CFM Bel-Air, and love it but retail is $3K and it still almost can't keep up with heavy media blasting use. Glad I didn't get anything smaller. Got it off CL for $750.

If you're gonna operate a hopper style blaster for more than 15-20 min at a time anything smaller than 20 CFM is gonna stress you out waiting.

Biggest unit at Lowes or Tractor Supply is 10 CFM, and $1200.
 
15 horse 100 gal two stage. with automatic water drain everytime it starts and stops. It still collects water in the trap above the glass beader under heavy use. Sometimes I have a guy on there for hrs. only stopping for break and lunch. keeps up with him and other shop use.
 
Like strokerscamp said, chk the cfm's at a minimum of 90 psi. Body work tools have the highest consumption of air. I have 2 sandblasters and my compressor 5 hp 2 cyl 60 gallon cant keep up. Also like smallblock said, get another tank that you can hook and piggy back. 2 stage is the way to go, but they are pricy....that will be what I get next.
 
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