Re: Spindle Motor - Stepper v DC Motor

Hi Peter,
Steppers have low torque at high speeds. You wouldn't be cutting
too much aluminum unless the stepper was really big. If you want
direction and speed control, you would be better off putting an
encoder on a spindle motor and using a variable frequency drive which
can manipulate the speed and direction for you. The encoder is fed
back to the control, so you could do tapping (assuming the software
handles it).

Jeff
http://www.xylotex.com

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Peter Cruickshank
<crankshaft_sg@y...>" <crankshaft_sg@y...> wrote:

> Hello all;
>
> Need some pros and cons regarding switching from my Sherline DC
> Motor to a Stepper Drive.
>
> Obvious advantages are easy speed & direction control which makes
> tapping & auto tool changes possible, what other advantages /
> disadvantages are there ??
>
> If I was to replace the 1/2 hp DC Motor with a stepper, what nema
> size, holding torque & drivers would I require to be equivilent in
> terms of torque ??
>
> Many Thanx
>
> PeterC