lathe speed

david · 13 Mar 2008

Hi everyone.
hope i am in the right forum for this question i have,
some of us remember model train sets with a transformer and the more we turned it up the faster a train would go,,
is it at all possible to do the same with a lathe motor.
mine starts from 500 revs up to 2000 but would like it start at a lower speeds ie= from zero revs to whatever i need.
i am just thinking about working large unbalanced pieces at slow speeds
and then increasing the speed as i get to round.
hope you understand the question
(i am not really electrically minded)
regards
david.

YorkieT · 13 Mar 2008

Yes it is possible to convert your lathe in to a variable speed model at a price.

http://www.haydockconverters.co.uk/vari ... ersion_Kit

Similar components can also be found on ebay.

Whitley · 14 Mar 2008

Hello David, I was pondering the very same question, and had a look at the phase inverters as a solution, but decided that the cost didn't justify it.

Like you I am not at all electrically minded and thought about a rheostat, except I couldn't find any except for light dimmer switches. apparently they would do work, but would burn out for a pastime, so not a good idea.
I saw these switches on ebay and did wonder if they would work on a single phase motor without an inverter. Anyone know???

ebay link

Mark Hancock · 14 Mar 2008

I believe you can alter the speed of single phase motors with a dimmer/rheosat type control but the problem you have is no torque/power at the lower speeds and will stall the motor. That is why lathes use inverters to run on single phase supply with a 3 phase motor. With this arrangement you get the torque across the full speed range.

If you think about it if the dimmer switch option worked why isn't it used in variable speed lathes as it's a cheaper option?

CHJ · 14 Mar 2008

Whitley":1yuj3gq7 said:
............
I saw these switches on ebay and did wonder if they would work on a single phase motor without an inverter. Anyone know???.......

On their own No.

They are just a remote control box for connection to an electronic 1phase to 3 phase convertor.

They allow you to place the controls where you want them as opposed to the ones on the front face of the invertor box which is normally fitted in a dust protective box.