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cuemaker
09-12-2006, 04:49 PM
I am thinking of picking up this air compressor from Eaton.

http://www.eatoncompressor.com/catalog/item/733537/450646.htm

Their ad makes it seem like they are delivering what they really say versus say something from HF, HD or TSC for the same size price range.

Can someone give me a more qualified opinion.

My uses will be limited. Some filling of tires, small spray gun, blowing some wood chips, MAYBE the occasional air tool like a sander (already have electric) but maybe more likely a small nailer.

MTNGUN
09-12-2006, 05:42 PM
I'm not an expert on the subject but some of the parts on the Eaton look an awful lot like the parts on my HF compressor. At that price, you know it's made in China, probably at the same factory that makes the HF compressors.

I'm sure it will be fine for your purposes.

I've had the HF for a couple of years now, used daily in a working shop. No problems except that it is noisy, and a little small for running my blast cabinet.

DR
09-12-2006, 07:26 PM
Yep, it's a generic contractor's type compressor. I have two that are identical, both different brands, Air Mite and something else, but I'm sure they're old enough that they were made in this country.

At that price your's is likely from offshore.

Kind of too bad when the name brand compressor people like Eaton get on the bandwagon and start pushing low end stuff.

garyphansen
09-13-2006, 10:24 AM
I have one just like it execpt a different name. I paid $89.00 from a Re-tool store. it was made in China. Mine has worked well for filling a tire now and then and blowing saw dust off everyint in the shop. Mine has not seen heavy use. I woul guess they are all the same except the color and name on them. I would look for the cheapest price. After I bought mine I found the same thing with a Shopforce name on it at another store for $69. It was painted red and mine is blue, it is just a good thing that I like blue better or I would have felt ripped off. HaHa! Gary P. Hansen

LarryinLV
09-13-2006, 10:47 AM
Cue,
That Eaton will probably do all you want in your list except run the sander. Not that it won't run it, but the tanks are too small to hold air capacity for most sander work. The compresser will be constantly on.

I have the Dewalt version and it is one of the better investments for doing trim work and other furniture related nail activity, portable, handy.

It does not replace the 5 hp 60 gal in the shop, or even compare.

Different tools, different jobs.

Millman
09-13-2006, 11:01 AM
Naw, get a bigger one.

cuemaker
09-13-2006, 11:33 AM
Unless Eaton is out and out lying or HF it telling the truth, the Eaton delivers more CFM

Eaton says : It has a CFM Displacement of 7.5 CFM and a Free Air of 6.5 CFM @ 40 PSI and 5.5 CFM @ 90 PSI.

Motor specs given: unit is 115V, Single Phase, 14 running amp draw

HF says: Air delivery: 3.8 SCFM @ 90 PSI, 5.0 SCRM @ 40 PSI

Motor specs given: 1-3/4 HP (rated) motor 115V, single phase

cuemaker
09-13-2006, 11:39 AM
Millman,

What I really want to do is buy this: http://www.eatoncompressor.com/catalog/item/518643/191066.htm

Use my 5hp rotary phase converter motor to run it and find an old air compressor tank for cheap.

I don't know what I am getting myself into (beside any potential old tank issues) in doing that.

It seems like it should work.

Rustybolt
09-13-2006, 11:42 AM
My advice to anyone looking to buy a compressor is to get one that is twice as big as you think you need. You will need the capacity sooner than you think.

pcarpenter
09-13-2006, 11:54 AM
I have this one:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=38898

It won't fit in the back of my truck with the cover on so wish I had gotten this one which uses the same compressor and tanks like the one you are interested in:

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=42321

Does the second one look familiar? ;)

I would never use this as a main compressor. Do get a bigger one. If you want something for occasional portable use, this is probably adequate. I wouldn't get cought up in an ad with a lot of conversation to make you think what they are selling is special.

I bought it for $69 to run a nail gun when putting up my shop building as I was not then set up for 220v service for my larger compressor. It did that job admirably. I now have it in my small basement shop/reloading room for blowing stuff out and you cannot use it for more than about 2 puffs but what it has to run...and it's loud. It draws real close to 15 amps, too. Stay away from a long extension cord. The guys at the store indicated that they have a lot of them returned as dead and the only thing that is wrong is that the motor thermal reset kicked out because they were using 100' of small extension cord and had voltage drop problems. They reset them and put them back out for sale at a discount....I got mine for $69 and have never had a problem.

If your air tool use means occasional use with a nailer....maybe. Anything else, forget it. These things are designed for filling tires and running a nail gun. Spray guns can seem like a low-use item....but more often than not, they are not. You need a compressor for painting that does not have to run a lot and has a big enough tank to allow some oil mist and condensation to settle out and the air to cool. You don't want to paint with warm, damp air. A separator is a good answer, but there is no substitute for allowing the air to cool before use.

Do stay away from the oliless compressors. In addition to the shorter life, they are *really* loud.

Paul

cuemaker
09-13-2006, 12:09 PM
Paul,

That is the one I gave the specs to in my previous post.

Ok, so what about spending $120 for the pump I listed up above, connecting it to my RPC motor and finding a tank?

This is my RPC motor: Allis-Chalmers Induction motor
5hp
1740 RPM
230/460 volts
13/6.5 amps

pcarpenter
09-13-2006, 01:17 PM
I have an RPC I use with several pieces of machinery. I have always decided that an air compressor is not a good application for an RPC. The compressor needs to be able to run whenever it wants and has a pressure switch that will allow it to come on whenever tank pressure drops below a certain amount.

Your RPC should never be started with a load on it. What happens when you go to fire up your RPC and you find that your air compressor switch was "on" because it leaked a bit since you were last in the shop. If you put a disconnect on the compressor and were religious about using it, maybe you could get around this.

RPC's make sense for machine tools that are only ever started by the operator. You can make sure to start the RPC and *then* the tool.

Eaton seems to indicate that it will run with a 2HP motor. Why not single phase?

You will spend some money buying the sort of tank that compressor merits and then having it hydro tested. You have to buy a pressure switch and an unloader valve etc. I have an Ingersoll-Rand unit with a true 5HP American made motor and a 130 psi maximum single stage heavy cast-iron compressor. It has an 80 gallon tank. It makes a true 17 or so CFM at 90psi. It is rated for continuous duty although I have yet to do anything (including using my blast cabinet) that makes it run continuous . I think I paid $700 or so from TSC. There are good solutions out there that are well under $1000 with no BS factor. You can generally save yourself some money by going with a big, single stage compressor. Most folks never need the 170 psi that a 2 stage will make and the compressor runs much cooler.

Do watch for the BS factor in HP compressor ratings and be sure to compare air delivery rates (CFM) at the same pressure. The 90PSI values are most useful as that is around the point you will run many air tools.

Paul

pcarpenter
09-13-2006, 01:35 PM
OK-- I was dense. I think you are suggesting running it off the motor that *is* your RPC which means a three phase motor on single phase. Even with the loss you take in HP, that would seem adequate although maybe a bit inconvenient. How would you run the RPC if you don't want to run the compressor?

I have nothing against building your own, but you may find it harder to find a *good tank* than you think....much less having it tested. A non-air compressor tank will likely not have all the necessary plumbing holes...which may mean some welding.....which certainly then merits hydro-testing. I am skeptical bordering on pessimistic about using a used tank as I tend to think that most folks do not keep them drained and the inside likely looks like the craters on the moon....waiting to rust all the way through.

I put a truck pull-type air bleeder on mine so I can give a pull on a cable to drain it. By making this operation *really* easy, I find myself bleeding it pretty regularly. The part was around $5 as I recall. Do not let this freeze however ! My uncle did the same and told me that the water settles into the valve and will take it apart when it freezes! Still, you should not be running a compressor in freezing conditions without synthetic lubricants.

Paul

ulav8r
09-14-2006, 09:44 AM
The first compressor mentioned is an oil lubricated compressor per Eaton's web page. Most of the contractors compressors you will find for sale are oil free. There should be a big difference in the life of the compressors because of this. Look at specifications, not just the pictures. Always buy at least twice the compressor you think you need.

motomoron
09-15-2006, 03:55 PM
I'd recommend that you look on Craigslist and the classifieds and wait for a 60 gallon 5hp unit.

I've worn out or used up a number of oilless compressors. I've had one quit in the middle of painting a motorcycle and had to retrieve the basement compressor to the garage to finish. I've had to rebuild and press bearings in to a Campbell-Hausfeld 'cause I really needed to use my die grinder...

No more.

It took a year of looking, but I got a 5hp 60 gallon Speedaire vertical in like new condition, used at a small repair shop for a couple years, for $350. I also got a Millermatic 185 Mig with an 80 cu ft C25 tank from the guy
for $550, but that's a different story.

I ran my bead blast cabinet for several hours last weekend, and painted a set of motorcycle bodywork, and it cycled regularly, but nowhere near continuously.

Having suffered through too many years of too-small oilless compressors, I recommend that you buy a big, used, nice, American made 2 stage 220V compressor. You'll be gald you did.

montanasoftware
09-15-2006, 07:32 PM
If you want to assemble your own air compressor from parts, it can be done, but there are a lot of details involved. I've been looking into this for the past month or so. Most of the ones that I have seen have the compressor mounted beside the tank on a shared base, rather than on top of it (easier construction.)

If anybody has any comments or helpful suggestions to what I've written below, let me know what you think.

For an air tank, I've been looking at water storage tanks. I live in a rural area, where people have well water, vs. city water. An electric pump sends the water into a storage tank in the basement, taken up to pressure. Then plumbing takes the water out from the tank to the house. When the rubber bladder inside the tank ruptures, the tank needs to be replaced. It's easy to find one of the old tanks around here, any pump installer will have access to an old one and will give it away free. And the nice thing is that they are already plumbed for air :-)

Better yet are the old galvanized water tanks -- stronger with no rubber bladder to block the air from getting out.

You'll also need a pressure switch to turn the motor off and on when the tank pressure gets above or below certain limits.

For *Any* air compressor, I recommend using plumbing ball valves for draining the fluid from the bottom of the tank, and a seperate "pull" type safety-release-valve on the side or top of the tank. Here is a ball valve:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=47195

You'll probably want a 1/4" or 3/8" valve, available at Home Depot or any plumbing supply store.

You'll need a pressure guage to tell you the tank pressure, and a regulator to set the line pressure. (This will allow you to keep the tank at 140 psi, and the line at 90 psi.)

Eaton has an extremely good reputation. I've been drooling over their products for long time. One of the good things about eaton-made pumps is that they are designed to run at lower RPMs than most other brands, resulting in less noise and longer life.

The pump I want is this one:
http://www.eatoncompressor.com/catalog/item/518643/547020.htm

The Eaton 13 CFM pump you linked to also looks very very good ... It is SOLID cast iron in the cylinders, head and oil sump. Most only have cast iron sleeves in the cylinders. And steel connecting rods are preferable to aluminum. I also like the big automotive-style air filters.

I'm no electrician, but i've heard it's bad to run a 3-phase motor on normal, 1-phase household current, even if it is 230 volts. So I'm sticking with a single-phase motor for my garage.

I have a cheapo oil-less compressor that only delivers 4.4 CFM at 90 psi. I don't like it. It takes forever to pump up a tire, and it can't keep up with air tools. I was thinking of taking the pressure switch, gauge, and regulator off of the little compressor and using those parts to build a big one from an eaton pump and used tank. The only thing left for me is to find a good 5-8 HP motor for cheap :-)

menace
09-15-2006, 11:50 PM
I have an old 30 gal Cambell Hausfield with a 5hp oilless compressor, IIRC.. I've run the balls off if for at least 10 - 12 yrs and I've expected it to quit for the last 5 yrs or so! It will run continuis with the glass bead cabinit, but does ok with all else, I need to find a replacement! I like the idea cuemaker has but wonder how well that compressor would run with a Honda 5.5 hp gas motor reduced to the correct rpm?? I would like the replacement to run on gas!!
BTW I've just recieved my first Harbor freight teaser flyer [like the ENCO, MSC, Travers,] monthlys. Something new I guess? Anyway, they offer a 18 CFM, 5 hp compressor for 124.99, do you think there made by the same people?

Steve

rsr911
09-16-2006, 12:43 AM
Someone needs to come out with a small rotary screw compressor. We put in a 15HP Boge rotary screw with a chiller evaporator and the cyclone separator. I ran 1.5" copper trunk lines with 3/4" feed lines to tie into the old plumbing that was originally hooked to two 5hp regular compressors and in just one day the clean dry air dried out all the water traps around the shop. I actually had to buy a bunch of oilers for the various machines we run. What's nice about rotary screws is nearly instant pressure, no tank is really necessary although I did install one. Pressure is set at 115 and NEVER drops below 100 even running a large diaphragm pump. A 3-5HP screw would be slick for a home/small shop.

Just for fun here's a link to Boge, we got the S15 model http://www.boge.com/US/Products/S15_to_S29/s15_to_s29.html

58 cfm at 115 psi :D

dhammer
09-16-2006, 04:40 AM
I put together an air compressor for my mobile tire repair business using one of Eaton's pumps, a 10 hp Kohler motor salvaged from a lawnmower and used 80 gal horizontal air tank. I bought the pressure relief valve, pilot valve etc from Graingers.

I don't know about using a domestic water pressure tank for an air tank.. I don't they are designed to run at 150 psi or more. Finding an air tank can be difficult. Eaton won't sell bare tanks due to liability issues. Graingers sell bare tanks and so does http://www.compressorworld.com/m/_general/default.asp

So far I have been happy with the pump from Eaton, they seem to have a good product at a reasonable price AND Eaton pumps are made in the USA.

montanasoftware
09-16-2006, 10:57 AM
I don't know about using a domestic water pressure tank for an air tank.. I don't they are designed to run at 150 psi or more.

You brought up a good point-- and people should be very careful about it. Water tank strength varies on which tank you are looking at. Some of the smaller wel-Xtrol tanks are only rated for 100 psi, but some of the larger ones are rated for 135 psi, which is plenty of tank pressure for me. The strongest ones are the old galvanized tanks, because they don't have the internal rubber bladders to provide the extended drawdown capabilities. The galvanized tanks should be able to handle 150 psi with no problems.

Rustybolt
09-16-2006, 11:08 AM
You can get air compressor tanks from W.W.Grainger

montanasoftware
09-16-2006, 06:39 PM
I put together an air compressor for my mobile tire repair business using one of Eaton's pumps, a 10 hp Kohler motor salvaged from a lawnmower and ...

Did your motor have a vertical shaft? If so, how did you use that on a compressor?

dhammer
09-17-2006, 01:36 AM
The Kohler has a horizontal shaft and was salvaged from a riding lawnmower.