To reduce the risk of manually shift the machine position during tool change make sure GRBL parameter $1=255 and that the Xcontroller “Idle current reduction” switch is set to OFF.
If you have homing switched installed you can:
- Home the machine once when powering up your CNC
- Jog only using the jog commands to where you want your work zero to be
- Click “Confirm Home Position” - this store the work zero relative to machine home (switches)
Now you have a stored work zero position, relative to machine zero.
This allow you to:
- If manually pushed or steps lost, reset your machine by rehoming, and “Use previous home”
- Do 1st tool job today, power the CNC down, restart tomorrow with 2nd tool etc.
- Restart an aborted or otherwise interrupted carve
Re-zero of Z may be required if something bit related have changed.