Step 12.33 — Z endstop: leave safe_z_home deliberately unreachable¶
Step 33 of 37 · Chapter 12 — Software: Pi OS image, Klipper/Moonraker/Mainsail, firmware, printer.cfg
(no image — see text)
Parts: none.
Do: Do not guess the nozzle-probe coordinates. Leave the section as LDO ships it and add a marker:
[safe_z_home]
## XY Location of the Z Endstop Switch
## Update -10,-10 to the XY coordinates of your endstop pin
## after going through the "Z Endstop Pin Location Definition" step.
home_xy_position:-10,-10 # TODO Ch 13 — measured on the machine, NOT a 350 preset
speed:100
z_hop:10
Check
home_xy_position is still -10,-10, and you understand that G28 Z will fail in Ch 13 with "Move out of range" until you replace it.
What you're looking at
[safe_z_home] is the XY position the toolhead moves to before homing Z, which here must be directly over the nozzle-probe pin. The shipped -10,-10 sits outside the machine's travel limits on purpose, so Klipper refuses the move rather than guessing.
Why leave it broken: -10,-10 is outside position_min: 0 for both X and Y, so Klipper refuses the move rather than attempting it. That refusal is the safety interlock. Substituting a plausible-looking value — bed centre, say — makes G28 Z drive the nozzle down at a spot where there is no pin, into the build plate. The LDO nozzle probe's real XY location is read off the machine during the startup wizard's Z Endstop page in Ch 13. src · src
Source: leviathan-printer-rev-d-sbv2.cfg · Klipper docs § safe_z_home · Voron startup wizard