Hello
I'm sure this question has been discussed extensively, but I' getting ready to buy a compressor for working on the truck (56) and I'm looking at an Ingersoll Rand 5 hp single stage 60 gallon from Tractor Supply for $710.00. Wanted to get some opinions on quality, price and anything else anyone can think of.
Thanks
Brad

 

No experience with IR compressors, likely they're made by some body else and re-labled........I don't think IR makes any thing anymore. Seems like for that price, or a little more you could step up to a 2 stage, which would be much better. Like night vs day. Single stage compressors have a hard time keeping up if you are painting or sanding etc. Look for the CFM rating..... 15 or above is good, 20 is better. Do you have 220-230v power hookup? the bigger the comp the more power it requires. My 2 cents. T/M

 

Yes, by all means pop the extra coin & get a two stage. Single stage comporessors are efficient up to 100 PSIG, above that and their Eff. falls off rapidly. If you are going to do any beadblasting you will want 125 PSIG. Even @ 110 the two stage will; put out more air per HP. You better have 220V power though with a 5 HP unit.

 

First decide what you will use the air for. Pick a compressor that will handle the heaviest use without running continuously (see duty cycle below). Buy the largest compressor you can get the first time. I have never heard of anyone complain that they bought too large a compressor, but compressors are the #1 tool to be upgraded in a short time of ownership because of disappointing performance of too small a unit.
VERY heavy volume user: sand blaster.
Heavy air users: paint spray gun, inexpensive versions of air tools like impact wrenches and sanders. (Cheap tools use oversized air motors to compensate for low tollerence construction and inefficient materials/design, wasting a lot of the air that goes thru them.)
Medium users: High quality air tools.
Low users: tire inflating, blow gun, nail guns, short burst tools.

Very heavy use will require a minimum of a 7 HP 2 stage compressor and frequent waits for rebuilding pressure. This size compressor will allow near continuous use of Heavy use tools.
Heavy use with pauses or continuous use of Medium use tools will require 7 HP single stage or 5 HP 2 stage.
5 HP single stage will run medium use tools with occasional breaks for pressure rebuild and/or cooling.
110V compressors with wheels or carry handles that plug into a standard household outlet will only handle low use tasks, no matter what their hype or specs say.

Electric motor HP is also often overstated. Don't go by the HP rating, but find the spec for the outlet or breaker size called for in the hookup instructions. 220V 20A = ~ 3 HP, 30A = 5 HP, and 50A = ~ 7 HP for practical comparison use.

Air output is also over hyped especially on the cheaper units. Most compressors are rated at X cu ft/min at Y pressure free air. This means how much air it puts out directly at the compressor manifold outlet without any restrictions. regulators, driers, oil seperators, piping, flex hose, tool type and design will all quickly and drastically reduce that output measurement at the point of use. It's easy to reduce the flow to useless levels. Cheap compressors measure output by calculating the swept volume x rpm. They boost the output by overdriving the compressor speed and soon burn out.
Given the same motor HP the following rules of thumb are reasonable assuptions:
a 2 stage unit will put out more air than a single stage with less effort because of efficiency. 5 HP 2 stage is approx = 7 HP single stage.
Multicylinder compressors are more efficient than single cylinders.
Don't even consider an oilless compressor. The compressor should have a crankcase full of oil like a gas engine.
Cast iron cases and cylinder liners with ringed pistons will be more efficient and last longer than aluminum compressors with lapped pistons.

Duty cycle: compressor specs should also include the rated duty cycle. This is given as a %, and represents the amount of time the compressor should be running vs not running. a 20% duty cycle means the compressor should not be run continuously for more than 12 minutes without being allowed to stay off and cool for 48 minutes out of each hour. Only HD overbuilt industrial grade compressors are rated for continuous operation. You would not want to use a compressor that has a just adequate capacity and a 20% duty cycle for painting your whole truck, and have to let the compressor cool for 48 minutes after every 12 minutes of spraying, the paint would dry in the gun/on the truck while you waited! Exceeding the duty cycle will destroy the compressor in short order and probably result in an excessive amount of oil and water to be pumped into the air line from the overheated compressor, and hot air to be sent thru the gun drying the paint too quickly causing a lot of overspray and orange peel.
Are you a member of one or more of the warehouse clubs like Sam's, Costco, or BJs? some of them sell stationary compressors in the tool dept. Check all branches within reach, each frequently carry different inventory based on the local demographics. For example we have 3 Sam's stores within 20 miles around us. One stocks large compressors, the other 2 don't???
Check out buying online from an out of state dealer as well. IR for example drop ships for free from their closest warehouse no matter who you order from, and the sales tax savings from purchasing out of state can be significant. I think mine had a charge of <50.00 extra for lift gate/pallet truck delivery inside my garage door.

 

I bought a 7 1/2 hp IR 2 stage a few years ago. As indiucated in AX posting, I bought online out of state. I have an engine builder friend nearby with a fork lift and saved the liftgate fee.made do with lesser units for a number of years. I have not been able to run the pressure down even with my large sandblast booth or my pressure pot. In fact I put a regulator on the pressure pot to keep the pressure down for sheetmetal sandblasting. I previously had 2 older single stage 3 hp sears feeding into a (free to me) 80 gallon horizontal tank.

 

I missed a 27cfm IR T30 on Craigslist last week by 2 minutes.. a local Line-X bed coating shop closed.. $500... new motor... man..

sam

 

Thanks for the advice. I will continue to look, but I am definitely going to go with a two stage. One more question. Any brands that I should definitely stay away from no matter what they list for specs?
Brad

 

Sam, watch when buying used. A lot of the commercial sized units go cheap because they are 3 phase rather than single phase. Most homes are equipped with single phase 220V service. To use a 3 phase you would need a phase converter ($$$) or up your service (even more $$$$!)
I have the IR 2 stage continuous duty rated 5 HP with 60 gal tank. Sells for ~ 1200.00.

AFA brands to avoid: Cambell-Housfeld have way overrated specs. "house" brands that don't have multiple independent parts sources in the states.

 

yeh, it was 1ph, 7.5hp... haven't seen many like that..
model 2475N7.5

I would have had to run new power line, but for $1500 savings, it would have been worth it to run another 6ga wire.

sam

 

I have a Champion 2 stage 5 horse 80 gallon and love it. I do wish that I had bought the 7 hp when I sand blast with my pressure pot. Just do a google search for Champion. They're in line with what you can get an I/R for. Also check Ebay for Champion compressors. That's not where I got mine, but there's a reputable business that sells them on Ebay.

 

I paid about $400 for a Harbor Freight 5hp unit with a 29 gallon tank. I love that thing!!! It was puking some oil out the breather until the rings seated, but has been purring away ever since. It is 220v, single phase and plugs in where the dryer does. After burning up two 110v units, this was my answer to carefree air service.

I don't have or plan to run a media blaster or anything that hoggish, but it has hung with everything else. I don't see a need to get more. They are available with a 60 gallon tank for a little more.

 

I've upgraded twice..


the 30gal, upright oil-less, sears thing, noisy as all get out..
then the campbell hausfeld from Home depot.. 60 gal, 5hp, 10.4 cfm
then an 80 gal tank, with a dayton twin cyl pump compressor, 100% duty cycle, 16.5 cfm. at 125psi. (used for $100 and the pump new in the box for $100). still can't quite keep up with sandblasting..

Sam

 

Definitely get a two stage 220V. Even an entry level two stage will be far superior to any single I have ever used. As far as brands, I was going to say anything but Harbor freight but I might get in troube from Randy.

I do use Harbor Freight tools Randy, but anything from there that comes with an electrical cord or a hardened cutting edge I regard as disposable.

 

I picked up a like new Quincy QT 5 on Craigslist and it worked great.

 

Brad,
what they all said..... but I'd add this... I'd rather have a used 'older' compressor than any of the newer 'retail' compressors. Most of what you see at H.D., Lowes, H.F., Sears ...(insert your favorite retail outlet name here) are all imports or built with imported parts in the states. I think you'd be better served with a better built/ used commercial unit. Check with the industrial compressor dealers or compressor shops in your area. Many times they will take trade in's on newer units from regular customers. They will check them out and offer them to their customers at a better price.

I bought a used and old Quincy 310 pump from a compressor repair shop 20 years ago and mounted it on a 80 gal horizontal tank I already had. I can't kill it ! That includes running 30 hours straight when a hose busted and I wasn't at home to hear it. (I don't leave it powered on when not in use anymore ) that's also why there is a 3/4" flex hydraulic hose from the compressor to the hard pipe now It's pushed by a 5 h.p. (industrial rated) motor and turning around 900 rpms. Solid cast iron sleeved block. The pump alone weighs over 200 pounds without the flywheel. There is a pic attached I took to show a friend how I did the starter wiring. The specs are down below basically 9+ ACFM at 175#s. That's another important spec .. look for ACFM (actual cubic feet/minute) most 'retailers' rate their pumps in SCFM (standard CFM) which is a number reflected from conditions that make their pump look best. Where ACFM is a rating of CFM under any conditions anywhere in the system. you can find more on ratings on comp sites or wikipedia.

look for names like Eaton, Bel-Aire, CastAire, Quincy and IR. You can get a lot more compressor for less money that way. Reputable dealers won't sell you junk and will always have parts for their pumps.. how long will you wait for a chijunk valve to come over on the boat ?.

One other note... when I plan on extended run time (blasting,painting, etc) I'll put a big fan where it blows over the compressor... yea I know, the flywheel makes air but more cooling is better and how much does it cost ?

later
John