Rubbish:( the only motors I found off the shelf are roughly £300. I thought steppers should be cheaper, but a 12Nm stepper is around the £100 mark:

http://www.zappautomation.co.uk/en/n...per-motor.html

and it needs a rather expensive controller (as it sucks 6Amps), which adds another £100 on top:

http://www.zappautomation.co.uk/en/d...304-am882.html

Of course there's a final slap on the face with the DC supply, which comes to roughly £70:

SPS407 Unregulated switching power supply.

so all together it's close price-wise to the DC motor (and something that Jonathan mentioned before, although at that point I thought I'd be able to get away with the cheaper DM422C controllers).

Jonathan, you've mentioned that if the speed is below the corner speed, the torque should stay at a reasonable level. How does one calculate the corner speed for a given motor? I'm asking because it might be better for me to use a 12Nm stepper 1:1, rather than doubling the speed to 600RPM and then using 2:1 to get the right spindle speed.

Regards,
dsc.