Who knows about air compressors and cfm requirements?

[kneedownnate]

You know the story;  had a bitchin 33 gallon upright craftsman compressor, but some undeserving jerk figured they needed it worse than I did.  I'm now sans compressor and am finding few options within my price range.  I need something capable of running a 1/2" impact and standard and hvlp paint guns. 

The paint guns say they run at like 10-13 cfm.  I don't think my old compressor was putting quite that out, but the 7 gallon craftsman compressor I found reasonably cheap is rated at something like 2.4 or 3.5, depending on psi. 

What do I truly need to run my stuff?  I've never really looked into it, but it seems I'm missing something on what it runs at and what the tool requires. 

[79coyotefrg]

my compressor is a 2hp 220 Volt with 2 cylinder compressor, on a 10 gallon tank,
it runs a 6 cfm  i think, does fine for my air hammer, 1/2 impact and air ratchet

[4RunnerChevy]

If your gonna run an hvlp gun then you will need the high cfm, or you will be stopping mid spray and letting your little craftsman keep up.  look in the 5+ HP range with a very large capacity.  Or switch paint guns.

[mudking82]

A 1/2" impact will run on just about any compressor since you usually are not using it for any length of time, unlike the HVLP gun.  If you end up getting a compressor that you know can't keep up with the spray gun, make sure you at least get one that has a 100% duty cycle, so that it can run continuously and not hurt it.  Such ones will have a real motor, with oil that will need changed from time to time.  The cheaper Craftsman or other brand "oil free" compressors are nice for the price, but they are not meant to be used for long periods of time, it says so right in the manuals. They are also way louder then a decent "oiled" one in my experience. 

I myself run two compressors, one is a 33 gal Craftsman "oil free", and the other is a 30 gal Husky Pro 100% duty cycle 2HP one.  I primarily use the Husky, since I know it will last longer, but when I need the extra CFM, I kick them both on, and even then they can't keep up forever when I am using my high speed cut-off tool for a long period of time.  That thing just sucks the air down turning at 22,000 rpm.  I have them both linked together with a custom setup I built so that I can have one fill the other, or vice versa.  They both run through a distribution block, which can also send full unregulated pressure to my tire changer. Then it goes through an inline FRL unit then out to my air hose.  And all my lines have inline ball valves in them to control the air flow.  It usually is all I ever need.  I would reccommend the Husky Pro compressor I have, but I know it won't even come close to keeping up with an HVLP gun. 

[toyyota]

Any professional paint spray gun will take at least 5 hp. Like your Welder, the duty cycle is also very important. 50% duty cycle means your compressor has to turn off, stop, and cool down half of the time you are using it. A huge air storage tank lets you plan ahead and save up air. The other thing for painting is cooling the air to let the moisture condense. A large air tank, or multiple tanks will help with this. Bottom line...to run a professional HVLP paint gun continuously, you need two 5 horse compressors with 50% duty cycle or one with 100% duty cycle. Either way, cool the air or you will have moisture problems in your paint. Use a portable fan to help cool your compressors.

[kneedownnate]

Thanks guys, good info!  I got a super cheap replacement, but it won't achieve full pressure. 

I did a little looking around and found a 60 gallon campbell hausefeld that runs at like 11-12 cfm for $400.  I don't want to spend that much and I don't have a good place to anchor it, but if I were to get something that big I'd probably drop some redheads in the concrete, bolt it down then weld the nuts to the studs. 

[toyyota]

I have always thought that spending money on tools that can make you money, is always better than spending on a quick thrill that gives you a headache in the mourning. But i'm kinda selfish. Buy the best tool you can afford, and keep it locked up. Most quality tools will last a lifetime.

[kneedownnate]

I do buy quality tools for work, too many really, but I don't make money with home projects.  If the house were mine there'd be no wavering, I'd just get the bigger compressor and lock it down properly.

[kneedownnate]

This is the compressor I may try and get from my old boss.  It's small but has a very high cfm output  http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&langId=-1&catalogId=10053&productId=100087756&N=10000003+90401&marketID=401&locStoreNum=8125

[toyyota]

Because of the small tank size, this is not a good pick for painting. I like the engine and pump setup. This is a prime candidate for a huge storage tank for home use, or a portable unit you could take on the trail for repairs.  

[kneedownnate]

Don't know why, but that doesn't come up as a clickable link.  Here's the specs:

A solid CAST IRON, twin cylinder pump for extreme durability. Offers 135 PSI maximum pressure and air delivery 11.5/10.2 SCFM @ 40/90 PSI. The unit features a reliable Honda OHV engine, rugged control panel with regulator, outlet gauge, and tank pressure gauge and two quick couplers. It also contains an efficient Solberg style filter, all metal belt guard, braided stainless steel discharge line and an oversized Hoosier pneumatic tire. Ideal for job sites with limited or no electrical supply.

    * Unique features protect the controls while delivering more air flow
    * Increased durability on the job site is provided by a braided stainless steel exhaust tube
    * Unique control panel for increased protection
    * Stainless steel exhaust tube helps eliminate vibrations
    * Enclosed belt guard cools pump to last longer
    * Bigger piston and cylinder offers lower RPMs to last longer
    * Ratcheting regulator ensures consistent tool performance and better results
    * Superior air delivery allows operation of more tools simultaneously and maximum tool performance
    * Convenient ''Wheelbarrow'' Design maneuvers with ease around the job site
    * Three year limited warranty
    * Compressor uses : Inflation Brad Nailers Staplers Finish Nailers Framing Nailers Roofing Nailers Drills Impacts Ratchets Screwdrives
    * MFG Brand Name : RIDGID
    * MFG Model # : GP90150
    * MFG Part # : GP90150