Control panel

Starts the homing cycle procedure with "$H" command

Starts the zero Z-axis search procedure using the command specified in the settings ("Z-probe commands" box).

Example command:

G91G21; G38.2Z-30F100; G0Z1; G38.2Z-1F10

Z-probe should be connected at GRBL control board at pin A5 and GND. For probes that engage contact when tool touches probe make sure to set $6=0.

When tool touches top of Z-probe and stops, it is not located at zero height. Zero height is at bottom of Z-probe. To set coordinate system for new Z0 you have to set coordinate offset for probe thickness.

This means expanding Z-probe command with G92Zn where 'n' is thickness of your Z-probe. For example if your probe is 5 mm thick "Z-probe commands" box should contain:

G91G21; G38.2Z-30F100; G0Z1; G38.2Z-1F10; G92Z5

Now after zeroing Z-axis you may type in command G90 G0 Z0 and tool would move right at the top surface of material (remove Z-probe before doing that to avoid damage).

For more info about G-Code commands, see LinuxCNC G-Code Reference.

Zeroes the "X" and "Y" coordinates in the local coordinate system by sending "G92X0Y0".

Zeroes the "Z" coordinate in the local coordinate system by sending "G92Z0".

Restores local system coordinates with "G92" command. May also move the tool based on the settings ("[ ] "Restore origin" moves tool in: Plane|Space").

Moves tool by "Z"-axis to safe position. Position coordinate can be specified in the "Safe Z" setting.

Position must be specified in machine coordinates.

Resets CNC with "CTRL+X" command.

Unlocks CNC with "$X" command.