C-Axis Minimum RPM

[RAMI]

On a doosan tt1500SY rpm range is advertised as 60-6000RPM. Does that mean when you are using polar countouring you need to have a minimum of 60rpm??? How does c-axis programing take into effect the min/max rpm of the spindle??? I am a bit new at this!
Thanks for the help.

[RICHARD ZASTROW]

The 60 rpm is probably to prevent "cogging" of the motor.

Or the motor needs a certain rpm to develop minimum torque.

New permanent magnet servo "torque" motors are supposed to develop full torque at 0 rpm. I'll leave that part to our resident elect. "guru's".

Dick Z

[Glacern]

There is typically no minimum C-axis feedrate. I'm not sure why the turning range on your machine is listed at 60-6000 RPM.

DZASTR is correct that full torque is developed at 0rpm. However, note that the torque is quite a bit lower than that of geared down rotary tables. With the C-axis engaged and the spindle at 0rpm, the spindle motor will correct its position if it's bumped out of place, but only after some error in the encoder position is detected (too late). So if you're doing some heavy drilling or lots of X-Y axis milling, use the M-code that clamps the spindle.

-Sol
Glacern Machine Tools