A limited amount of NGC lathes shipped with the C-axis engagement offset set wrong.
The NGC lathe no longer uses the C-axis tool change offset parameter for engagement. To achieve alignment of the C-axis Servo motor to the C-axis drive gear, we simply set the spindle orient offset parameter to align with the C-axis, when the C-axis is at its home position.
If you have a C-axis machine in your area that is experiencing problems with the C-axis, perform the following procedure:
C-Axis Engagement Offset - NGC Lathe
To download the C-axis test NC program click here.