Quote Originally Posted by PotatoMill View Post
Why not closed loop?
Personally I'm not a fan of closed loop steppers... Open loop steppers are cheap and Servos are great performers, closed loop steppers are neither...

I think it is possible for you to achieve your desired level of performance using the cheaper open loop steppers. 3Nm stepper should probably be around about right directly coupled to a 5mm ball screw.

Servos you'd be looking at 100-200W I believe.

Hope this helps!

Fenza