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DCP
09-18-2011, 11:24 AM
I have a Ingersoll Rand air compressor 2hp 3450 rpm 110v motor and the Compressor
I actually have everything (all the fittings and regulator )but the no tank.

All in very nice condition

I was going to us it on my lathe but the rpm is wrong

What can I do with it?

What might it be worth?

oneokie
09-18-2011, 11:29 AM
Make a jackshaft with pillowblock bearings and pulleys that will reduce the rpm to what is needed for the lathe.

Matt3357
09-18-2011, 02:52 PM
What size is the compressor? Are you wanting to just use the motor for the lathe? If you want to sell the rest let me know.

BTW, I am in Illinois as well. Down by St. Louis.

Matt

DCP
09-18-2011, 04:22 PM
Matt

Everything was rated 2hp
Looks like to buy the stuff to use it may cost to much.
For me it may be cheaper to jusy buy a lathe motor

rtracy2001
09-19-2011, 08:32 PM
There are a number of ways to change the speed of an AC motor, the most common is a variable frequency drive. They can be had for around $100 and up IIRC, but you generally get what you pay for.

A point to look out for is a class action lawsuit that came up against several compressor manufacturers a few years ago. It seems the HP ratings were peak ratings only, and not continuous ratings. For an air compressor, it wasn't a big deal since they have high startup requirements, then run for a while at moderate load, then as the tank gets full the load increases until pressure is reached and the motor turns off (hopefully to cool for a while before starting again.) For something like a lathe you want a motor that will supply constant torque and speed (HP= torque x speed). Better check your motor and make sure it is the one you need.

felix
09-19-2011, 09:10 PM
And, make sure the motor has sufficient cooling at the RPM used, most especially in constant torque mode. Misuse is the primary cause of motors being sent back to the manufacturer for credit or exchange. ... felix

DCP
09-24-2011, 04:43 PM
I have come to the conclusion that I need to find a tank of some sort (any recommentions)

Or just sell all the parts. How much do you gentlemen think its worth?

Thanks for all the help

uscra112
09-24-2011, 07:25 PM
I've used VFDs a number of times in special machine tool applications. At reduced RPM you also get proportionally reduced torque, which is what you care about for a lathe drive. I would not do that option.

Used motors are often incredibly cheap. New, that motor might be $200, but I often buy them at farm auctions around here for ten cents on the dollar. I grab them whenever I can, because if I ever need one, I do NOT want to pay retail. So far I actually have put two of my bargains to work. Why they go so cheaply I don't know. With copper where it is, you'd think they'd bring more, but they don't So selling and buying another is probably not going to work very well for you either.

You might be able to work a trade with a machinery dealer.

DCP
09-25-2011, 10:28 AM
I was thinking $250.00 for everything, its all in very nice condition. Its made in USA
HF has compressors pretty cheap so I maybe way off.

or maybe a old propane tank. I had a old freon, air tank once


Ingersoll Rand air compressor 2hp 3450 rpm 110v motor and the Compressor
I actually have everything (all the fittings and regulator )but the no tank.

Simonpie
09-25-2011, 12:39 PM
Oddly enough, tanks are usually the last thing to go. You should be able to find a compressor with a dead motor or pump on Craigslist for free. Don't worry about it fitting mechanically. The tank can sit in a different location with a hose. If you find a moderate to small one, go for it and set your system up. Then spend your time looking for a cheap portable job like a horizontal 10 gallon on wheels. This can be plumbed into your shop with a quick disconnect, to boost storage capacity, or charged and unplugged to make a mobile tank. It wouldn't paint or sand, but it will rattle axle nuts off a truck OK.

DCM
09-25-2011, 04:23 PM
At what speed do you want the input of the lathe?? Pulley ratios are a direct ratio of the diameter of the pulleys, a 2" pulley on the motor @ 3450 and a 4" pulley on the lathe would give you a 1725rpm input a 6" pulley on the lathe would give you a 1150 rpm input.

There are a couple of advantages to using this setup.
One you are INCREASING the availble torque at the lathe and if you do not overly tension the belt it can act as a clutch. :lol:

If you made a setup as Oneokie described you could put multiple pulleys on ti for multiple speeds also. Pulleys can be had fairly cheap at your local farm supply store and they usually have "pillow Blocks" too. They usually have a good selection of belts and soft bar stock too.

uscra112
09-28-2011, 12:44 PM
One you are INCREASING the availble torque at the lathe and if you do not overly tension the belt it can act as a clutch.

+1 to that.

If you can't find what you need locally, go to www.mcmaster.com.

If they don't have it, you don't need it. Very quick delivery via UPS/Fedex, no minimum purchase, and they tale your credit card. I use them quite a lot - especially with gas so expensive, it's cheaper than driving to town.