Thanks for the reply so far I tend to agree with you, what they came up with is 2 off 8 Nm motors at 3000 rpm and 1 off 6 Nm @3000 rpm for the Z axis ( which I believe is an overkill on Z ).
The speed that I am trying to get is around 600 ipm that is so I can position fast or go to tool change fast, and is the maximum I can go without stress on the 40mm ball screw, perhaps I can live with a slower unit, I want to build it to machine up custom doors in hardwood.
The Siemans quote includes PCU servo drives and a handwheel, I think they are about 15K too high looking at some of the sites for servo motors, the biggest 5inch units 10Nm with drivers at around $1400 US each
The reason I am keen on the servo instead of steppers is I am a little nervous of the torque drop off in the steppers, perhaps this is not a real problem as the maximum force is on acceleration.
I am pleased you highlighted the rate of acceleration to 100ms I fully agree with you.
Please keep that help coming
Kind regards
Chris  |