RE: [CAD_CAM_EDM_DRO] Subject: Re: big stepper on ebay

I don't think it would be a great modification. It would probably work, but
I would be concerned about 2 primary things:
1 - Large steppers tend to have relatively low maximum rpm. Small lathes
tend to like high rpm. If you use a belt drive to gear it up you will have
little torque. Also, just by the nature of steppers your torque will drop
rapidly with rpm so your top spindle speed regardless of how you achieve it
will not have a lot of power.
2 - At slower speed the motion of a stepper may tend to aggravate chatter. A
stepper does not have a smooth rotation at a fixed speed, but moves in a
series of steps. At lower rpm this would be most pronounced and is
effectively full speed to the next step and then a pause followed by a full
speed move again.

Only way to tell for sure is to get a motor and try it.

Tim
[Denver, CO]

> -----Original Message-----
> I am in the process of converting a taig lathe to cnc. My
> question is can a
> stepper motor of sufficient power be substituted for the AC spindle drive
> motor? That way with the proper DC power source the spindle forward and
> reverse and variable speed could be controlled by the computer.
> Any and all
> suggestions appriciated.
> Thanks in advance. BILL.
>
> FAQ: http://www.ktmarketing.com/faq.html