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Vizslarunner
2nd February 2017, 03:13 AM
How do you pick out a new motor for a lathe. The one on it is from the 50s

Oldgreybeard
2nd February 2017, 08:56 AM
There are many experienced turners on this forum who will be willing to give you advice, but you need to give them some informstion.

What lathe are you talking about? - Maker and model as a minimum

What type of turning are you interested in doing?

Do you have access to 3 phase power or only single phase 240V?

Do you want to incorporate variable speed capability?

Regards

Bob

Oldgreybeard
2nd February 2017, 09:01 AM
Just read your earlier post - is it the motor intended for the Craftsman?
Is there a reason for not replacing it with a motor of the same size and specs?

Bob

Vizslarunner
2nd February 2017, 09:48 AM
Yes it's for the craftsman. And I would be ok with changing it for the same thing that's on there. Just not sure how too. Right now it's an old GE Ac motor

GeoffW1
4th February 2017, 06:08 PM
Hi,

There are several outlets. I bought one for a lathe from this bunch on eBay

http://stores.ebay.com.au/CONON-MOTOR

It seems good enough. It has an overload circuit breaker fitted.

First look at the power of the existing motor, you would not want to buy a weaker one. If the rating plate is missing have a look on the Net at similar size lathes. At a guess it is probably about 2 kW or less if a single phase motor on a small to medium lathe. Then look at your power supply. If you have only a 10A household supply you are limited to 1.5-2 kW. Some would say 2.2 kW max, and it might work OK but don't use long runs of light gauge cable to it.

Then pay attention to :

the bolt spacings in the existing mounting plate (or flange). These are part of a standardised frame scheme. 90L and 100L are common frame sizes in the 1.5 kW - 2.5 kW range. You can get adapters.

http://testweb4.iecworld.com/xindatong/upload/2012040917125876.jpg

Also if you want to re-use a pulley, look at the shaft size. Again you can buy adapter sleeves for a too-large pulley bore.

Then there is the motor speed you need, probably 4-pole (1400 RPM).

For a lathe get a capacitor start/capacitor run motor, this will do best for startup torque, as the motor has to start itself and the whole headstock and chuck, and maybe backgears and leadscrew as well.

Take very careful note of how the old motor is wired in before removing it. Nearly all lathes have a reversing lever, and this is usually wired to a drum reversing switch which flips the polarity of the start winding in the motor. The new motor will be supplied with terminal straps (or bridges) in the motor contactor box, connected for forwards running, and these have to be removed to enable the lathe connections to function correctly. If unsure about how that goes call in an industrial sparky. A household sparky may not know.

Cheers

Treecycle
4th February 2017, 08:09 PM
Very handy site Geoff. I have saved it for future use but not sure if it is suitable for Vizslarunner. Does PA in the location stand for Pennsylvania?

GeoffW1
4th February 2017, 09:25 PM
Oops,

I saw the original post in a "recent posts" list from the MetalWorking forum, and did not notice it was most likely a woodturning lathe. Therefore half of what I said does not apply except the comments about the motor mount, shaft size, and noting how it is wired.

No, the motor I got did not come from Pennsylvania, it was shipped from Melbourne.

Cheers

Vizslarunner
5th February 2017, 04:35 AM
Yes I'm Pennsylvania