air compressor size????

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swifter

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WHat is a good size tank and motor hp for keeping things like da sanders moving ,i have a 30 gal tank now and the air depletes right away and can't keep up--Thanks
 
You need to take your biggest tool, determine the air usage, and add some "fudge factor."

Tank gallons has NOTHING to do with an air compressor capacity. All a huge tank does is to allow you a few more seconds before kick in, and you get to sit there a lot longer to wait for it to pump back up

Take published compressor cfm figures with a "grain of salt."

You want cfm specifically rated at 90 psi.

cfm listed at say, 40 psi makes it sound "bigger" and ratings at scfm (atmospheric inlet pressure) makes one sound bigger YET

But even ratings at 90 much be viewed with a raised eyebrow. Consider "who" is claiming them. If it's ANY Chineseo outfit, be suspicious

And don't buy a direct drive anything, nor oil less. If possible, you want a cast iron pump, belt drive.
 
I have a 5 hp, 60 gallon compressor from Mac tools. That thing works great.
I would not go any smaller then that. You need the reserve for the air tools.
I do have a problem using a sand blaster with it. But my normal tools, impact,
air ratchet, die grinder and air chisel. works great. I wish now I would of
gotten a bigger tank.
Just think BIG.
 
80 gallon tank, will have to check the cfm. Has no trouble supplying anything I have hooked to it, will normally cycle on and off.
 
I got a 6.5 horse Craftsman with a 60 gallon tank and have no problems it's 13cfm @ 40 psi and 10.5 @ 90psi. I filled it up with Mobil 1 when it was new and never looked back. The oil in it still looks new but I might change just for chits and giggles.
 
One of the most misunderstood and incorrectly advised and described areas of the hobby.

67dart273 is 100% correct.

CFM trumps all other ratings. Period. Unfortunately it's the most difficult rating to find.

5+ HP, iron head, and belt drive are good clues that you are looking at a quality unit.

Also be wary of unrealistic HP and amperage ratings. A 6HP motor is not going to draw only 20 amps. Start and run draw are also different.

I was recently searchng for a secondary/portable unit, and the Highest CFM 110v unit I could find was a DeWalt/Emglo 2HP, 8.4 CFM. It will run my blast cabinet, but just barely. I paid $300 used, but they are over $800 new.

Don't be afraid of a good quality (Quincy, Bel-air, etc) used unit.
 
I've got an 80 gallon tank, 230volt 5.4HP rated at 13.5 CFM @ 175PSI and I always wish for more capacity. Die grinders, media balsting etc. really consume a lot of air. Go BIG!!!
 
Something to think about is that with a quality compressor you can get parts for the pump. With a bargain one you replace the pump as a whole. It all comes down to how much volume, psi you need and how long you plan on keeping it. As with most things in life you get what you pay for.

Another thing to think about is your power supply. 110, 220 single phase, three phase. Depending on your power supply you might only be able to go so big.

I wouldn't be afraid to buy another used quality compressor.
 
ok--so here is another question--What about adding a second tank to my existing unit???????????? can it be done or am i talking out of my a**--steve
 
What i have now--30 gal tank-155 psi max-1.9 hp with 7.0cfm @40 psi--5.7 cfm @90 psi----there is a 60 gal tank 3.7 hp 135 psi rated one on craigslist for $400.00 bucks right now---will that new one be any different????? Or there is a 10hp with a 120 tank for $1000.00 but I would make a lower offer on that one--Steve
 
You can add another tank which will give you more volume, which will keep you going a little longer before your compressor cycles. Your time to cycle will be longer which will be harder on your compressor.

The 10 HP is probably going need 3 phase power but will run anything you throw at it.

Here is a Craigs list search of the midwest. You can filter it down to states since I don't know where exactly you are in Wisconsin.

http://www.adhuntr.com/2012/05/midwest.html?cof=FORID:11&ie=UTF-8&hl=en&newwindow=1&q=air+compressor&cx=partner-pub-9413604915893153:ip92pyyiu4t&as_q=more:region&as_oq=&sa=Sear

I paid 1/3 of the new price for mine and made a 300 mile round trip to get it.
 
Cfm, cfm, cfm!

Gallons of storage and PSI mean nothing after you exhaust the tank.

If you are running a tool that uses 8 CFM on a 5 CFM comp.....
 
Ok according to this
http://www.jennyproductsinc.com/howtochoose.html
You need 11 - 13 cfm to run a dual action sander. They say to add 30% so that brings it up to 14.3 - 16.9 cfm to run a DA continuously. I think the 30% is a little high but the link above has some good buying info even though it is a little biased.
That DA is one air hungry tool that get used for long stretches at a time.
 
i had a cambell housefeld for a few years 15.6 cfm at 100 psi. just did the job running da and inline sanders but when i would run my sandblaster i would have to stop after 10 minutes.it was 7.5 hp and 80 gallon bought used for 500.00

sold it and bought a international commpressor with80 gallon 7.5 hp. same size unit but it has rating of 25.6 cfm at 125 psi. let me tell yhou.....what a difference it is a 2400.00 air compressor but worht its weigh t in gold. i give out before the compressor when sandblastiing. i have gone trought8 100 lb bags of sand and it will still be holding 100 or more psi. bought it from friend for 300.00 he bought some 150 gallon 15 h.p and is used commercially 18 hours a day running 5 air tools at a time on big rigs. that one cost hime 14k

above posters,are correct. all you really need to worry about is cfm at given psi.
my 15.6 was great, but when using for long period of time, i could see it slowing down,and air comming out would be real hot, which also slows to tools down
 
THanks for all the Info guy's!!!!!!! looks like I will start searching in the meantime I have a employee that said he will buy my old one!!!! Going to hit craigslist and search HAVE A GREAT WEEKEND !!!!!!!!!!!!! Steve
 
I have run all my air tools and painted with a 5 Hp 30 gal 220V compressor.
 
I was told by an electrician to stay away from 3 phase because the power companies wont send 3 phase to a residence only a business.
 
chryslerfat said:
I was told by an electrician to stay away from 3 phase because the power companies wont send 3 phase to a residence only a business.
Click to expand...

Most residences don't have 3 phase available, and if they did, it would cost a considerable amount to have 3 phase run into the house. But if you got let's say a good buy, a REALLY good buy on a 3 ph belt drive, you might be able to change the motor to single phase and still come out good. Just depends on "the deal."
 
YY1 said:
Cfm, cfm, cfm!

Gallons of storage and PSI mean nothing after you exhaust the tank.

If you are running a tool that uses 8 CFM on a 5 CFM comp.....
Click to expand...

Exactly! It's all about CFM, not the tank size. CFM is the cubic feet per minute a tool draws and it it draws 8 cfm at 90 psi and your compresssor is only putting out 5 cfm at 90 psi it'll never ever keep up no matter if you have a tank as big as a freakin semi hooked to it.
 
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