Marlin: Babyz not persisted between prints?

[ir-fuel]

Even if I leave my printer on, it seems that the babyz setting is back to 0.000 at the start of each print.

Is this normal?

[AnHardt]

Yes.
The idea of babystepping was to just move some steps, bypassing all registration.

[ir-fuel]

Ok. So the best thing to do is to get the value and put it in my slicer for the next prints then.

[cdedwards]

or edit your height/z offset

[KevMags]

Configuration_adv.h, Line #604 (in my Version) //#define BABYSTEP_ZPROBE_OFFSET // Enable to combine M851 and Babystepping.

If I understand this correctly your babystepping will be applied to your z offset permanently.

[ir-fuel]

But it is not persisted.

[KevMags]

I haven't used it but a M500 may save it to EEPROM, where it should persist.

[thinkyhead]

In the current bugfix-1.1.x branch:

• Babystepping with BABYSTEP_Z_OFFSET will allow babystepping which also adjusts the Probe Z Offset. The same value as set by M851.
• You can use M500 to save the new Probe Z Offset to EEPROM.
• You must re-probe the bed to benefit from the new Probe Z Offset. It is not applied to your previous bed leveling probe data.

[ir-fuel]

I'm all pretty new to this, so I might need a bit more explaining, but:

I am currently running the bugfix branch on my CR-10S. How do I reprobe the bed so it uses the new probe Z offset? The only things I currently use is 9 point bed levelling and then using the baby z to finetune the distance (which for some reason is always too high after my bed levelling using a sheet of paper, but that's a different discussion) while printing.

How exactly would I persist this baby Z then? Right now I just copied the value in my slicer software in the Z offset field.

[bjarchi]

@ir-fuel Hopefully I can help

With BABYSTEP_Z_OFFSET enabled, you would do as @thinkyhead said - adjust your offset using babysteps to get the correct height, use M500 to save the offset to EEPROM, and then (re-)issue G29to (re-)probe the bed.

Without BABYSTEP_Z_OFFSET enabled, you can still fine-tune your z-probe offset to avoid having to finetune each time. M851 will print the current probe offset to the terminal; M851 Zx.xx allows you to change it. M500 persists the new value to EEPROM when you're happy with it.

AntCLabs has a pretty good document for BLTouch installation that includes z-offset calibration here - look for the section titled 'calibration.' One note - if you have _SOFTWARE_ENDSTOPS enabled and you need to move outside the z-bounds to calibrate your offset you can do this. You need to issue M211 S0 to disable software endstops before making the necessary Z moves, and then M211 S1 to re-enable the software endstops once you've found your correct z-offset value.

[ir-fuel]

I did another test today.
It seems baby z isn't remembered at all?
Test:
while printing, double click the button and adjust baby z
Click again to quit that screen
double click again
baby z value = 0.000

Is that normal?

Config files included.

Configuration_adv.txt
Configuration.txt

[AnHardt]

Yes.
The idea of babystepping was to just move some steps, bypassing all registration.

All !

If you are talking about BABYSTEP_Z_OFFSET - that could be different.

[ir-fuel]

Also, is baby Z applied at the next command to be executed, or is it real time?
If for instance I send a command to extrude a line over the entire width of the bed, will baby Z influence that line while I change its value during that extrusion or will it only be applied once the next command starts?

[thinkyhead]

Also, is baby Z applied at the next command to be executed, or is it real time?

Babystepping is accumulated and applied immediately.