Induction V's Carbon brush motors

[Tazmaniandevil]

Now apart from the obvious benefits of better torque outputs and less maintenance, is there any reason not to choose a lathe with carbon brush motor?
When I was doing my apprenticeship, machines mainly had induction motors because they performed better, were quieter, ran cooler, and tended to last longer.
There appears to be a plethora of lathes available with carbon brush motors rather than induction motors. Surely they must be reliable enough or companies like Axi wouldn't produce so many.
My current ML8 has a ½HP induction motor, which works like a dream. I am looking to upgrade sometime this year, depending on price/budget. Should I go for a bigger lathe with carbon brush motor for £xxx or hang off and pay a bit extra for one with induction motor?

 

[MMUK]

Nothing wrong with carbon brush motors, they've been around for long enough. The main disadvantage for me though is the noise compared to an induction motor. That would be about the only reason I would go for induction. However, a lifetime supply of ear plugs for me would still be cheaper.

 

[Tazmaniandevil]

One of the lathes I looked at said the lifespan of the brushes was 500 hours. That's what concerned me. I generally only get on the lathe at weekends, days off work, and summer evenings. Assuming I run the lathe 2 hours each day at the weekend, that means replacing the brushes about every 2 years or so. That seems a very short period.

 

[Grahamshed]

For me the noise would be reason enough. Turners can spend quite a bit of time playing with their spinny bits and you don't really want to have to cover your sticky out bits if you don't have to.

 

[RogerP]

Now apart from the obvious benefits of better torque outputs and less maintenance, is there any reason not to choose a lathe with carbon brush motor?...........

Noise, noise and noise!

 

[Spindle]

Hi

I'm not sure how to tell which lathes are powered by brushed motors but do know that all brushed motors are not equal in noise production. I think the best thing you can do is go and have a listen to prospective purchases in operation, (remember it will sound quieter in a large space).

On brush life I see that one of the Axi offerings recommends replacement every 60 hrs - that sounds quite frequent to me.

Regards Mick

 

[YewTube]

I think your choice will be between a 'low' cost variable motor (DC with brushes) or not (AC induction, pulley or VFD)

Bill

 

[RogerP]

......... However, a lifetime supply of ear plugs for me would still be cheaper.

....depending on individual circumstance but there could be the family and neighbours to consider - hours of someone using a noisy brush motor isn't fun .....

 

[Spindle]

Hi

This has a brushed motor and whilst I've not heard it in operation I'd be very surprised if the noise was intrusive and pretty certain that ear protection is not needed: (I'm sure we have owners on here that could confirm this)

Are there lathes being supplied with noisy universal motors? Which ones?

Regards Mick

 

[Dalboy]

Hi

This has a brushed motor and whilst I've not heard it in operation I'd be very surprised if the noise was intrusive and pretty certain that ear protection is not needed: (I'm sure we have owners on here that could confirm this)



Are there lathes being supplied with noisy universal motors? Which ones?

Regards Mick

I have the white coloured predecessor of this one and the action of turning makes more noise than the machine

 

[CHJ]

There may be some differences with so called DC motor lathes.
Nowhere can I find the actual specification of the motors but the nomenclature DC MOTOR may not be a reference to an old style Universal motor. Which tend to be noisy because of the speed needed to develop the torque and associated commutator noise.

They could be one of several variations on electronically switched Permanent Magnet units.

Short brush life may not be purely mechanical abrasive wear but associated with high current loading caused by design.