BLtouch bed leveling does not honor boundaries

Taz 6, BLtouch, Archim2, Hemera using DO v2.0.0.1rc30 (was doing this on 2.0.0.1rc29 as well)

When I issue a G29 P1 the BLtouch moves off the X0 edge of the build plate when trying to get points 15+.

Also, when attempting G29 J the print head slams in the X300 side when trying to get that corner of the 3 points.

I have set my probe offset using M851 X-57 Y-5 as my BLtouch is to the left and forward of the nozzle.

What else do I need to change? TIA

This is not surprising, currently the PROBING_MARGIN and MESH_INSET are set to zero, which I doubt is appropriate for LulzBot printers.

Either PROBING_MARGIN or MESH_INSET would need to be adjusted. There are different implications to doing so. If PROBING_MARGIN > MESH_INSET then certain probe points will always be ignored. If MESH_INSET > PROBING_MARGIN then all points will be probed if they are reachable, but you will decrease the area of the bed for which bed leveling is active, which will limit your print volume.

Not sure which configuration is most desirable.

I would give up probe points before print volume. First layer quality hasn’t been a problem for me.

I just released r31 with PROBING_MARGIN and MESH_INSET set to 10. Please let me know if it helps.

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You, sir, are a gentleman and a scholar. This completes my upgrade to Archim2, Hemera & BLtouch. My Taz6 is feeling more 2021 than 2016. Thank you - UBL is sweet!

Looks awesome! Is this the guide that you followed for adding everything? Any changes? The thingiverse listing for the bracket has an update that it’s out of date blah blah…

Yes, I used that guide. It all worked fine for me. If you’re recycling the brass inserts you will need 2 more for the new carriage.

@marciot I think we may need to go with 15 - my print head is just barely bumping the far end of the Z axis during G29 J. Even 12 might do it.

@sr3jan: Try r32, I bumped the margin to 15 mm.

Works great, thank you!