Working on a small lathe with live tooling for light cuts in plastic. I am using a servo motor to drive the spindle motor that doesnt have encoder feedback (all positioning control is internal to the motor). 

I am struggling a bit with changing back and forth between spindle operation and "C" axis operation for live tooling. While running the spindle my M3 or M4 codes jog the "C" axis at a rate equal the the desired RPM. When I want to use the live tooling another M Code adds the "C" axis into the coordinate system. By then I have lost my position because I have been jogging the axis outside of the coordinate system.

Is there a way to count my encoder pulses while I am jogging? I really need to be able to call the axis current position, divide the total number of pulses it has moved by the counts per spindle revolutions, and then redefine that axis at its current position. Do you see any way of doing that?

b. Current Position = 360 Degrees X.89 = 320.4 Degrees

4. How do I re-enable the C axis at 320.4 Degrees?

Does my approach here seem at all reasonable? I am pretty stuck on points 1 and 4 if anyone knows how to help.

Thanks,

Scott

Modulo360.c-14936.txt

Hi Scott,

That should work.  See the attached example.  The MCode Action will need to be configured as Exec/wait/Sync to resync the Interpreter to the changed position.

Regards

TK

 

Working on a small lathe with live tooling for light cuts in plastic. I am using a servo motor to drive the spindle motor that doesnt have encoder feedback (all positioning control is internal to the motor). 

I am struggling a bit with changing back and forth between spindle operation and "C" axis operation for live tooling. While running the spindle my M3 or M4 codes jog the "C" axis at a rate equal the the desired RPM. When I want to use the live tooling another M Code adds the "C" axis into the coordinate system. By then I have lost my position because I have been jogging the axis outside of the coordinate system.

Is there a way to count my encoder pulses while I am jogging? I really need to be able to call the axis current position, divide the total number of pulses it has moved by the counts per spindle revolutions, and then redefine that axis at its current position. Do you see any way of doing that?

1. How many pulses did I jog? (Example: 2,456,712)
2. Divide that by Pulses Per Rotation (Example: 800)
3. Get the remainder:

a. 2,456,712/800=3070.89

b. Current Position = 360 Degrees X.89 = 320.4 Degrees

4. How do I re-enable the C axis at 320.4 Degrees?

Does my approach here seem at all reasonable? I am pretty stuck on points 1 and 4 if anyone knows how to help.

Thanks,

Scott