is a power tailstock really necessary on a cnc lathe? other than drilling what operations can be done with a power tail stock? lastly how would you build one? i was kind of thinking about driving mine with a stepper attached to a ball screw under the lathe bed. the only thing i'm having a problem figuring out is how to clamp the tail stock to the bed the current clamp does not maintain constant tension and is only used for locking it down. although the real question is...is this really necessary if you have a turret tool changer on the cross slide?