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harbormaster
11-14-2004, 12:23 PM
I see a different air compressor in my not too too distant future.

The 2hp one I currently own just does not have the volume I need to run my die ginder, or bead blaster for any length of time. It constantly runs and cannot keep up.

What SCFM should I shoot for? Is it necessary to get a 240 volt one?

Its frustrating having to wait every 10 minutes for the compressor to build pressure back up when using the die grinders wire wheel to clean parts.

Any and all suggestions would be appreciated.


What do you have?

MOP
11-14-2004, 12:41 PM
Scot just an opinion, you need a 10 gallon tank and 5HP or better compressor. I had a 5 gallon with a 3HP for a long time it was not bad for wrenching but was marginal for blasting anything of size. 220 volt units actually use less current a good move.

Phil

gcarter
11-14-2004, 02:11 PM
Scot, the fundamentals of electricity says you need 240 volts. Lowes has an 11CFM, 6 HP, w/ about a 50 gallon vertical tank and small footprint for about $420.00. I've been looking at one of these for awhile.
If your breaker box is in the garage, it shouldn't be difficult to add an additional outlet. A 30 amp outlet should do very well. :yes:

Formula Jr
11-14-2004, 02:47 PM
I've got a Devilbiss Pro 4000, 3.5 hp, 20 gal. It is oil-less permanently lubricated which works well for small volumn painting, nailers and hammer wrenches.

It comes 120 Volt and is marginal for sanding. This is about as big as you can go with 120 volt. I have fried many extention cords and plugs. What I hate most are the funky water drain valves most of these come with. 240 is the way to go. I can change it to 240. That will not increase the cfms but will save me plugs and cords.
Sanding and beading use a lot of CFM. All air power tools are not created equal. My DA sander is a cheap one and a pig with air.

It puts out 6.7 CFM @90 PSI. I need twice this for sanding.

pmreed
11-14-2004, 03:14 PM
The man to talk to is Poodle; this is his business. Your needs are on the small end, but run them by him, and you'll get the straight skinny on what you need. :smile:

Phil

Lenny
11-14-2004, 08:33 PM
Scot. I have an Ingersoll Rand, 80 G tank, cast iron two stage pump, 7.5 hp 3ph. Seems adequate for anything BUT blasting. Blasting needs a LOT of ooomph.

I have 30 ACFM (actual cubic feet per minute) It is plenty. I would look for a 5HP, cap start, 60-80 tank, 2 stage compressor. Cast is nice but not neccesary for what you are doing. You will need about 40 amps @ 240 to spin it up tho. #8 wire is a must.

:) Have you mailed my flag yet?

Cuda
11-14-2004, 08:46 PM
I have a six hp, 21 gallon compressor rated to 6 cfm@90 psi. It doesn't have enough to run a da sander very well. I wished I had gone bigger.

Lenny
11-14-2004, 10:01 PM
Cuda, 6HP and 6 cfm doesn't make sense. First off is yours 240V? second, is there even a head gasket on it if it is only making 6cfm? You should have about 25cfm unless it is an import 120V "peak HP" ordeal. :confused:

Cuda
11-14-2004, 10:15 PM
Lenny, you made me check to see if my numbers were correct. I don't know if it's an import or not.

Formula Jr
11-15-2004, 06:18 AM
Cuda, you would need a 4476 watts to run a 120 volt electric motor to 6 HP. Thats 37.3 Amps. Which can't be, since if your motor could suck down that much juice it would fry all the wires unless you were running #8 AWG. So their little claim isn't possible unless you wired up the motor to run on 240. Even then its at the very edge of what two 20 amp #12 Wires can handle. So <3.5 hp is the upper limit for a standard #12 20 amp/120 Volt circuit. After doing the math, I can see now why I've been frying plugs and extension cords! :bonk:

harbormaster
11-16-2004, 04:47 PM
OK. God watches over fools and children.

I traded 50 bucks worth of cheap spare parts for a nice clean upright Air compressor.
100% duty cycle. 120 volt 5 hp with a 26 gallon tank. Should work for me now.

What type of oil should I top off the compressor with?

Lenny
11-16-2004, 05:10 PM
I use Ingersoll-Rand air compressor specific oil Scot. Cheap stuff. Lordco or equivalent might have it. I believe it resists frothing and the dusty/dirty environment better than others. I don't really know.

marcdups
11-16-2004, 05:17 PM
harbourmaster it should take 30W NON DETERGENT oil !!