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thefixer
20th April 2008, 10:43 PM
G'day forumites

I have been toying with the idea of changing the motor on the MC110 and I have a few questions that I hope someone can help me with.
1. What is the governing factor between "horse power" and "watts"? My lathe has a "1 horse power" motor PIC 1 and my pedestal drill has a "550 watt" motor. PIC 2. So what's the difference, if any? Both motors look identical and have almost identical information stickers on them. Even the castings and cooling fins are the same so I assume they come from the same factory. And if my grandfather (rest his soul) had a horse on his farm with the same amount of power as the so called "1 horse power" motor, I think he would have shot it:( Anyway, as you can see both motors have the same RPM rating and one draws more current than the other, otherwise not much different.

Next query. I was given a clapped out elcheapo compressor that no longer works but the motor is in perfect working order. PIC 3. But I have no idea as to what the RPM rating is. No info on the labels except to indicate that it is a "2 horse power" motor. PIC 4. I have worked out the machanics to convert to this motor, just need to turn up a new shaft on the machine lathe and make an adaptor plate to fit the lathe and bobs your uncle.
So, can anyone tell me if this type of motor is powerful enough and has the appropriate RPM rating to make the conversion worth the effort. It would be nice to be able to turn big stuff without stalling the lathe all the time:(( And yes, I have searched the web for model numbers, serial numbers and manufacturers, all to no avail.
Hopefully somebody has been here before me and can help:rolleyes:

Cheers
Shorty

China
20th April 2008, 10:56 PM
750 watts=1hp aprox

thefixer
20th April 2008, 11:17 PM
750 watts=1hp aprox

Thanks China.
One query down, a couple more to go:wink:

Cheers
Shorty

Frank&Earnest
21st April 2008, 12:57 AM
Hi Shorty. 2HP is more than enough to power the lathe, IMHO too much. RPM should not really be an issue, more than likely is 1400 like the others but could be 2800 or, much less likely, a fraction of either, depends on the number of poles, nothing to do with power rating, don't worry about the technicalities. If it's not worth for you getting access to a hand tachometer (~$100?), just compare it by eye with one of the other ones, it should be fairly easy to see if they are about the same speed or one is double the other. In the end what matters for you is what comes out at the other end of the belt, if the speed of the motor is different you have to change the size of the pulleys. This would affect torque but not to a dramatic extent, I guess.

artme
21st April 2008, 08:07 AM
:iagree: with :wts:

Ivan in Oz
21st April 2008, 08:16 AM
750 watts=1hp aprox


Remember that is output.

You 'might' have to put in.....Say 1000Watts to get that ONE HorsePower out,
perhaps more.

OGYT
21st April 2008, 08:31 AM
How hot does the motor get when you turn it on and just let it run for a couple of hours? That may be a factor. I had an air compressor motor that got hot as heck after just 5 minutes of running. Nope, it wasn't the input tubing... it was the motor. :)

funkychicken
21st April 2008, 09:50 PM
V x A = W

240V x 10A = 2400W ( The max a normal houshold plug can take, which is why you don't get tools that suck more than 2350 or so - with the exception of 3 phase and 15A or 20A machines)(No I didn't learn any of that at school:roll:)

240V x 4.8A = 1152watts

According to what Ivan said, that means that your lathe is sucking 1152watts and outputting 750w or 1hp.