A Newton is about 100 grams and motors are usually rated by holding torque rather than pull in torque. You need to see a torque against speed graph to know if you are in the right ball park. If the mill is of any size then you'd want NEMA 34 steppers or servo's for speed.

Suggest you wind some kind of tape around one of the handles and then see what weight you have to lift on the end of it before you feel the kind of torque you reckon would make a cut.