Servo as a Sherline spindle motor ?

Thanks to all who responded to my question about my 5mm pulley bore. I have some coming and I'll try to bore them out and cross my fingers.

That pulley is destined for the end of a double-stack NEMA17 stepper that will be used to drive the cross slide of a Sherline lathe that I'm FINALLY getting around to CNCing properly.

One thing I'd like to try on the Sherline is CNC threading.

I see two ways to do this.

1. Put a servo on the spindle and write a bit of custom code; no real problem, or

2. Put a nice fat motor on the spindle (so there's no worries about it slowing down) and use one of the "spindle sensor" options.


Option 1 is certain to work AND I have all the bits at hand; spare gecko G320, a choice of servo motors, and some L series pulleys.

The one little fly in the ointment is that the choices for servo motors are

. one that's SEEMS a wee bit small or
. one that's WAY WAY WAY TOO BIG and would be wasted in this application.


The smaller motor is an older EG&G Torque systems ME2610. It is physically pretty close to the same size as the stock Sherline _AC_ sewing machine motor, if that means anything. (It's an old lathe).

I can find no specs on the PRECISE motor, but I did find some specs on a similar motor from the same manufacturer (same dimensions, similar part number). That motor is rated at 29 OzIn continuous, 150 OzIn peak. This does not seem like a whole lot of torque to me.

On the other hand, I can't stall it with 36 volts driving it by grabbing the 1" pulley, so maybe 150 OzIn is more torque than it seems.


Anyway, I'm looking for thoughts, opinions and experiences; all comments gratefully accepted.



Alan