Managing motorized z-axis

[ChrisMolloy]

I have NEJE MAX 4 V2 E80 with z-axis stepper.

I am trying to set up lightburn so that when I enter the material thickness, the z axis will move such that it is in focus.

I have set G54 z offset to -17 which is where it is focussed on the bed.

When lightburn runs, it raises the z axis to the material height, putting it in focus.

My problem is that the beginning of lightburn gcode raises the z axis in relative mode by the material thickness, which for thicker material sends z axis out if bounds.

Everything works as expected in absolute mode, but not in user origin mode.

Not sure how to resolve this.

[MikeyH (Mike Hembrey)]

Two choices:

1. Use the Absolute Coords for everything except the rotary. This is recommended most of the time.
2. Search the Lightburn Docs and the Youtube videos for an explanation on how User Origin and Current Position works. With both of these, you have a shifting coordinate system in play. If you are working in spacial coordinates (XYZ), keeping up with the math can be challenging.