Hi-

I am having trouble with bilinear bed leveling with the 1.1.x bugfix release. I can not determine if its the sensor being flakey or if its the firmware.

Here is a video of Autohoming and G29 leveling. The bed does not properly retract/advance when its probing points 6, 7 & 8.
[photos.app.goo.gl]

Here is a copy of my logfile with debug turned on. At around line 2590 is where i am determining the probe trigger value. The Bilinear grid is reported at line 3130.
[drive.google.com]

2018-06-01 00:13:14,228 - Recv: Bilinear Leveling Grid:
2018-06-01 00:13:14,229 - Recv: 0 1 2
2018-06-01 00:13:14,231 - Recv: 0 +3.911 +3.733 +3.591
2018-06-01 00:13:14,233 - Recv: 1 +3.939 +3.877 +3.873
2018-06-01 00:13:14,234 - Recv: 2 +8.945 +8.948 +4.000
2018-06-01 00:13:14,236 - Recv:
2018-06-01 00:13:14,237 - Recv: G29 uncorrected Z:9.00
2018-06-01 00:13:14,238 - Recv: corrected Z:4.04

I leveled the bed corners as best I could before I autoleveled, so I really don't believe the mapping or corrected Z of 4.04mm.

Is the probe being flaky or is it Marlin?

Thanks
sinneD

You mesh points are very large. This implies you do not have your Z_PROBE_OFFSET_FROM_EXTRUDER set correctly.

You mesh point values should be centered around 0.00 mm.

thanks for the reply. maybe i was not specific enough- yes, i understand that i should be somewhere around 0 for the mesh points. this is how things were looking when i first got the probe.

my Z probe trigger heights have been slowly but steadily creeping up. when i got the probe, it was triggering around 2.6mm. when things started going weird, i backed-up and calibrated. then i got like 2.8mm. things worked for a while, then got weird again. i recalibrated then i got a value of 3.2mm. then again after a few days, until i have gotten up to 3.8mm.

did you watch the video? what would cause the probing to go the other way? points 6, 7, & 8 dont retract/return like they should.

i am trying to figure out if this is a probe issue or marlin issue.

Edited 1 time(s). Last edit at 06/02/2018 11:29PM by sinned.

There have been some changes to the probing code over the last 2 weeks in response to issues of probing on the edge of the bed.

It is very possible the lastest code addresses some of what you are seeing. Can you try the current code?

This WAS with the current code, bugfix from 5/26/2018.

What should I be using instead?

That code is a week old. And changes have been made to it.

If the changes don't fix your issue, please start a thread at [github.com] and we will get the right people focused on it.

Edited 3 time(s). Last edit at 06/04/2018 01:20AM by Roxy.