Compressors???

[pistolpete]

Been searching and searching and figured there'd be someone can give some insight.

Is it possible to paint (not high quality by anymeans) and run say an air die grinder on a 120V compressor? I have been looking and from the specs painting is a stretch. As far as a die grinder or a small air saw, I can not really find what cfm and pressure they need... I know there are a million and 30 answers to this question. Just looking for some real worl experience from someone who has done it.

I know I should be looking 220V, but I dont have the floor space, and I only have one 220 outlet in the garage and would prefer not to tie it up with a compressor all the time... Any opinion/comments would be greatly appreciated.

 

[TiredIronGRB]

You can as long as it's not constant use. I recently bought an 80 gallon upright at Lowes for $750...I must say it was well worth it.

 

[pistolpete]

I guess thats kind of what i meant... what type of use or length of use would you get using a die grinder... or paint gun type thing... Just trying to see if it is worth getting say a 20 gal 120v (or something along those lines) or not.

 

[donsrods]

For years I got by with a Sears 20 gallon 2 hp compressor, then moved up to a 60 gallon 240 volt. It was much better, but I still ran out of air with sandblasting, running DA sanders, etc. Finally bit the bullet and bought a 3 cylinder 5 hp compressor from Eaton Compressors. Now, this 5 hp motor is about 4 times the size of the ones you see at Home Depot, etc. It was the very best investment I have ever made. It is in use constantly, and keeps up with whatever we are doing.

Eaton is also a fantastic company. After about a year the first compressor head started making noise. Eaton sent me a brand new one at no charge, didn't even want the old one back. A couple years later the motor stopped running, same thing, sent me a brand new one, no questions asked, scrap the old one. The new set up has been running fine since then.

A big compressor makes life so much more pleasant and you can do so much more.

Don

 

[TiredIronGRB]

Mine (from Lowes) is a 3 cyl 5 hp.

 

[Sniper]

Most tools are CFM rated at 90 PSI. Seems to be the industry standard. Ingersoll Rand lists their Die Grinders at 3 Cubic Feet per Minute. 1/2" Impact at 4.4 CFM, and Dual Action Sander at 17 CFM, Air Hammer/Chisel at 3 CFM, and 3/8th Ratchet at 5.5 CFM.

Offshore tools pretty well have the same ratings except the DA Sander is rated at 4 CFM, quite a bit less. I have listings for two Air Body Saws, one is rated at 4 CFM, and the other is 2.2 CFM average use, and 8.8 CFM cont. air consumption. Not sure how they figured that, unless it can be throttled at the trigger. A standard non bleeder paint gun runs from 9.5 to 13.5 CFM. The HVLP type paint gun, (High Volume Low Pressure) is rated a bit less at 7 to 9 CFM.

So, after all that, a 120 volt motor driven compressor will on average put out 4 CFM at 90 PSI. Leaves no margin to play with I'm afraid. And you can bet the CFM numbers are a bit optimistic by the tool manufactures. (Kind of like cars and H.P.) The 115 volt motor will likely be pulling a 11 to 13 amps on a 15 amp circuit continuously since it can't keep up, unless you stop. (Warm wiring, and tripped breakers.) A 230 volt motor will use the same power/amps, it just splits it equally on both 115 legs at 5.5 to 6.5 amps each leg. So then the wiring system can handle it, without being run so close to the max. I think we have all tried to get as much compressor and air volume as we can on a 115 volt system at one time or other. Short bursts, and giving it time to recover is the norm as a rule. A big tank will prolong the time between rests, but it won't cure it. It also takes longer to fill and recover. A big enough compressor to stay with the tools, and motor to drive it is the only real way around it.

 

[29desoto]

I agree, once again

I agree with don and sniper here. I had the 2 hp, 20 gallon unit for a while, and it did pretty good. Then I got the 60 gallon, 220 Volt, and it has done me well. I used to paint cars, and the 60 gallon would get me around once at 40 psi to the gun, and only cut on once or twice. Then while it was flashing off, I could drain the tank for water, and refill.

I would suggest considering a 220 unit myself. Cost does not have to be terrible. I bought my oil free unit from Sears, and they discounted it as "open box" item. And getting 220 is not a big deal. I'm sure either you, or someone you know could mouse the wiring to provide it to one plug. And like sniper said, you would be dividing the amperage between two wires. Works good.

Lots of luck either way. And by the way, I have found that much of the time I do not need full air pressure to make a tool work well. My DA sander works ok at 60 PSI.

 

[pistolpete]

Kind of what I was guessing. I have recetnly rewired the garage, and to be honest hadn't had the compressor thought until afterwards, my issue there now is that I have a single breaker left in my panel (and thats after putting in a 4 slot subpanel in the garage already for the 220, lights & outlets). Also in a 14 x 22 garage floor space is at a premium and figured i didnt have the room for anything large at all.

Running the wiring isnt an issue as I can do most of it myself, and get the brother in law (who is an electrician) to do all the terminations in the panel, as I tend to feel that is best left to someone other then me. But still leaves me with the issue of having not enough space in the panel for yet another double breaker.

Thanks guys for the comments/advise. May have to wait until I am at a new house before I can really consider getting the garage totally set up the way I want, however long that will be...

 

[29desoto]

one more thought

Pete, my 220 volt 60 gallon sears unit is an upright. It stands in my corner, and probably doesn't take up 2 feet by 2 feet. I put it behind the door in the shop, and ran a long hose out.

And as far as the breaker goes, if you are running a welder, couldn't you just scab the compressor off it? I don't often weld and use air at the same time, and with a 60 gallon tank, you can run some small tools a fair amount on the tank. Just a thought.

 

[pistolpete]

And as far as the breaker goes, if you are running a welder, couldn't you just scab the compressor off it? I don't often weld and use air at the same time, and with a 60 gallon tank, you can run some small tools a fair amount on the tank. Just a thought.

It's what i have been debating actually. Not that I would be using it constantly, but when I do use it I'd want it to do what I need.