You are correct that the Doosan is programmed using the C to control the spindle rotation.Hi All:
Do I infer correctly, that the example of the Doosan in the second video must be using the C axis to control the spindle rotation rather than just turning the spindle and counting encoder pulses.
I believe this to be true because a dumb spindle does not normally behave this way...it just turns at a constant, commanded rate.
Seems to me, if true, that driving the spindle as C axis is fundamentally different from just running the spindle at low RPM and capturing encoder counts.
In the C axis instance, is the spindle motor acting exactly like the X or Z axis motor acts...ie is the spindle motor moving to a commanded angular position governed by what the control is explicitly telling it to do.
If that is so, can a lathe without a C axis capability EVER be made to behave this way?
Would you need to change the spindle encoder to something different, and would you need to change the control to allow it to command the spindle with something more than just "GO" at whatever RPM?
Must you have this to do what Alex wants to do?
I can't comment on what would need to change on a 2-axis lathe to accomplish this. I know on some of my older machines with C-axis, the C-axis needs to be engaged by stopping the spindle and then programming a code to shift a gear which engages a servo motor to control the C motion. Newer machines I have don't have this extra motor, and everything is done by the main spindle motor.