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Table of Contents
Understanding the gcode Z offset
…currently a work in progress…
Good Further Reading
- Ellis's Print Tuning Guide on First Layer "Squish"
Related wholly to non-tangential squish
General concepts of squish and non-tangential shape
Squish will be different for different layer heights
Squish will be different for different filaments
- Material
- type
- brand
- color
- Build plates
What does good squish look like?
Setting the gcode offset value
Klipper commands
The gcode z offset is set with the SET_GCODE_OFFSET
klipper command and you should read its documentation, at https://www.klipper3d.org/G-Codes.html#set_gcode_offset
All other methods of changing the value just equate to this command. You can set it to a absolute value like
SET_GCODE_OFFSET Z=0.075
or adjust it relative to its current value like
SET_GCODE_OFFSET Z_ADJUST=0.3
Fluidd GUI
Fluidd provides easy to use controls and displays the current value, live.
Why not by Screen
Workflows using the Screen can be problematic as proper attention needs to be considered for how this value may be being changed by other controls. It is not displayed live and the value shown can be stale. This can result in issues when it send incremental value changes. Saving it in the Screen's workflows can also trigger changes to other values unintentionally. It's better and easier to change the value in the console or in the How should I set the z offset.
Can this be realistically calibrated using the paper method?
No.
At best the paper method will asymptotically approach the thickness of the paper being used. Yet this is an arbitrary value nearly in the ball park of what a typical z offset might be. The z offset we're seeking is filament dependent and will vary by the filament being used. We're seeking a correct affect on the shape of the extrusion's cross section, a “smush”, and that can't be defined by some arbitrary height.
Is the CC setting the z offset or setting the probe z offset?
(…work in progress…)
The Elegoo Centauri Carbon has sensors to “set the z offset”, yet it's realistically setting the probe offset. Prints will oftern stil require a z offset adjustment which can be set in the slicer.
Z Probe calibration -- the other Z Offset
(…work in progress…)
How the Probe and GCODE Z Offset Relate
(…work in progress…)