[3.6.0-rc.2] Z-probe hits bed and U not moving running Mesh

tcamguil

Hello,

I am running an IDEX 3D-printer with a klicky as the Z-probe and two toolheads one on the XY axis and the other one on the UY axis.

I have three issues :

The first one is that during the G29 calibration the machine will sometimes fail to detect the "status change" of the Z-probe and will go all the way down breaking the Z-probe before generating a "Error: G29: Probe was not triggered during probing move" message.
I have tried increasing the Z lift to 0.5mm in between two probes without success. H2:0.25 => H2:0.5
I also tried to increase the recovery time to 0.5s thinking the Z-probe "status" was not updated in time. R0.0 => R0.5
The second one is that the XY mesh calibration is only applied to the Left toolhead (the one connected to the X motor).
Is there a way to apply it to the U axis without having to run the mesh calibration twice?
The third issue is that while the mesh calibration is almost running as expected when the G29 is running on the left toolhead. When I try to run the mesh calibration with the right one (the one using the U axis) the mesh is advancing along the Y axis as expected but it does not advances along the U axis, the toolhead stays at the last position the U axis was moved to before starting the G29 command and is simply going back and forth.
I have tested every release between 3.5.4 and 3.6.0-rc2 and it seems this is a new issue to 3.6.0-rc2:
- 3.5.4 is moving the toolhead diagonally (U and Y are moving)
- 3.6.0-beta.3 - 3.6.0-rc1 is running fine
- 3.6.0-rc2 is not moving along U

extract from the config.g file

[...]
;Kliky L
M558 P8 C"10.io0,in" H2:0.25 F1200:120 T18000 K1 R0.0 A15 S0.005 ; set Z probe type to bltouch and the dive height + speeds
(the forum thinks this is an URL hence the commas)
G31 P500 X42.00 Y0.00 Z-25.000 K1 ; set Z probe trigger value, offset and trigger height
M556 S50 X0 Y0 Z0 U0 ; set orthogonal axis compensation parameters
M557 X0:300 Y0:250 S50 ; define mesh grid

;Kliky R
M558 P8 C"11.io0,in" H2:0.25 F1200:120 T18000 K1 R0.0 A15 S0.005 ; set Z probe type to bltouch and the dive height + speeds
(the forum thinks this is an URL hence the commas)
G31 P500 U-42.00 Y0.00 Z-25.000 K1 ; set Z probe trigger value, offset and trigger height
M556 S50 X0 Y0 Z0 U0 ; set orthogonal axis compensation parameters
;M557 U0:300 Y0:250 S50 ; define mesh grid
[...]

; run mesh.g

; Mesh compensation
T-1
M290 R0 X0 Y0 Z0 U0    ; clear babystepping
G28    ; Home all towers

;pickup the klicky
M98 P"0:/sys/pickupprobe.g"
M558 F120 K1    ; Reduce probing speed to prevent scares
M556 S50 X0 Y0 Z0 U0    ; set orthogonal axis compensation parameters
M557 U0:300 Y0:250 S25:30    ; define mesh grid

G1 Z5 F1200    ; Approach tool - BL Touch
G1 U-42 Y0 F15000
G29 S0 K1    ; Proceed mesh compensation by probing, saving heightmap.csv correction map file and displaying the matrix
if result != 0     ; If the Mesh failed
    abort    ;  cancel the calibration process
G29 S1    ; Activate meshgrid compensation
G29 S3 P"0:/sys/heightmap_U.csv"    ; Save meshgrid U
M376 H{max(5,(move.compensation.liveGrid.deviations.max-move.compensation.liveGrid.deviations.min)*20)} ; Set the mesh bed compensation taper to 10% of a layer height.

;drop
M98 P"0:/sys/dropprobe.g"
G28                                               ; Home all towers

Board Name:

Duet3-6HC
Toolboard1LC
Firmware Version:

MB6HC: 3.6.0-rc.2 ( 2025-03-31 12:17:13)
Toolboard1LC: 3.6.0-rc.2 (2025-03-31 12:22:41)
DWC Version: 3.6.0-rc.1
Raspberry Pi: No

tcamguil

Downgrading the Toolboard1LC firmware to the version 3.6.0-rc.1 (2025-02-28 15:03:36) seems to have solved the first issue.
Even increasing the probing speed does not seems to be able to reproduce the issue with the old firmware.

droftarts

@tcamguil said in [3.6.0-rc.2] Z-probe hits bed and U not moving running Mesh:

;Kliky L
M558 P8 C"10.io0.in" H2:0.25 F1200:120 T18000 K1 R0.0 A15 S0.005 ; set Z probe type to bltouch and the dive height + speeds
G31 P500 X42.00 Y0.00 Z-25.000 K1 ; set Z probe trigger value, offset and trigger height
...
;Kliky R
M558 P8 C"11.io0,in" H2:0.25 F1200:120 T18000 K1 R0.0 A15 S0.005 ; set Z probe type to bltouch and the dive height + speeds

Do you have one Klicky probe, or two? You seem to be defining two, on different IO inputs. Or is it the same Klicky, but it depends which tool head picks it up?

You have K1 set as the probe number for both probes, so most likely only one of them is actually being configured; the second effectively overwrites the first, so when the 1st toolhead (using the CAN '10' board) picks it up, it's looking on the wrong input for the probe response. Same for G31. Send M558 K# to check what probes are defined. Use a different K number for each probe. I don't know which probe number you are using in your 'pickupprobe.g' etc macros, but you could pass a parameter to the macro based on the tool number.

As far as I'm aware, the mesh should be applied to both tools. Please post your full config.g, maybe it's a config issue.

There is an issue running mesh probing on the U axis, it has been reported before, and your third issue sounds similar to this: https://forum.duet3d.com/topic/37165/issue-with-szp-on-secondary-idex-toolhead

Ian