Duet 3 BLTouch probing issues



  • I have tried RRF 3.1.1 and 3.2 beta 4 and had the same issue on both. I am currently on 3.1.1

    I do not have a BLTouch available to try, but have tried BLTouch versions 1.1 and 2.2 that I pulled off of working printers to troubleshoot with. I am currently using a knock off.

    The problem I am having is when I probe I continue to get -5.000 readings. It appears to be z homing just fine with some notables I will mention below, but when I try to G32 I get missing probes or the following:

    G32
    Leadscrew adjustments made: -5.000 -5.000 -5.000, points used 3, (mean, deviation) before (-5.000, 0.000) after (-0.000, 0.000

    I cannot get a 4 point to complete all of the probes. Only the 3 point seems to actually register the probes enough to get that adjustment readout.

    I have also tried a probe test and I get the same thing:

    M98 P"0:/macros/Probe_Test"
    G32 bed probe heights: -5.000 -5.000 -5.000 -5.000 -5.000 -5.000 -5.000 -5.000 -5.000 -5.000, mean -5.000, deviation from mean 0.000

    I also notice that even when I z home the first probe will read 0.75mm the same as my probe offset. The next 2 will read -4.25 which is where i think that -5.000 is coming from.

    Here are the uploads.
    retractprobe.g homez.g homey.g homex.g homeall.g deployprobe.g config.g bed.g



  • ; Configuration file for Duet 3 (firmware version 3)

    ; General preferences
    G21
    G90 ; send absolute coordinates...
    M83 ; ...but relative extruder moves
    M550 P"RailcoreOrange" ; set printer name
    M669 K1 ; select CoreXY mode

    ; Drives
    ;X&Y
    M569 P0.0 S0 ; physical drive 0.0 goes backwards X
    M569 P0.1 S1 ; physical drive 0.1 goes forwards Y
    ;Z
    M569 P1.0 S1 ; physical drive 1.0 goes forwards Front Left Z
    M569 P1.1 S1 ; physical drive 1.1 goes forwards Rear Left Z
    M569 P1.2 S1 ; physical drive 1.2 goes forwards Right Z
    ;Extruders
    M569 P0.3 S1 ; physical drive 0.3 goes forwards
    M569 P0.4 S1 ; physical drive 0.4 goes forwards

    ;Leadscrew locations
    M671 X-25:-25:372 Y-12:242:115 S7.5 ;Front left, Rear Left, Right S7.5 is the max correction - measure your own offsets, to the bolt for the yoke of each leadscrew

    ;Stepper Mapping and Settings
    M584 X0.0 Y0.1 Z1.0:1.1:1.2 E0.3:0.4 ; set drive mapping
    M350 X16 Y16 Z16 E16:16 I1 ; configure microstepping with interpolation
    M92 X200.00 Y200.00 Z1600.00 E837.00:837.00 ; set steps per mm
    M566 X1000.00 Y1000.00 Z100.00 E1500.00:1500.00 ; set maximum instantaneous speed changes (mm/min)
    M203 X24000.00 Y24000.00 Z900.00 E3600.00:3600.00 ; set maximum speeds (mm/min)
    M201 X3000.00 Y3000.00 Z100.00 E1500.00:1500.00 ; set accelerations (mm/s^2)
    M906 X1500 Y1500 Z1000 E800:800 I20 ; set motor currents (mA) and motor idle factor in per cent
    M84 S30 ; Set idle timeout

    ; Axis Limits
    M208 X0 Y0 Z0 S1 ; set axis minima
    M208 X270 Y250 Z300 S0 ; set axis maxima

    ; Endstops
    M574 X1 S1 P"io1.in" ; Map the X endstop to io1.in
    M574 Y1 S1 P"io3.in" ; May the Y endstop to io3.in
    ;M574 Z0 S2 ; Z endstop controlled by BLTouch probe

    ; Z-Probe
    M557 X15:215 Y15:195 S20 ; define mesh grid

    ;BLTouch
    M558 P9 C"^io7.in" H5 R1 F120 T6000 A5 S0.02 B1 ; Define the bltouch input on io7.in
    M950 S0 C"io7.out" ; Define the bltouch servo on io7.out
    G31 X-30 Y0 Z0.75 P25 ; Set the offsets for the bltouch

    ; Heaters
    M308 S0 P"temp0" Y"thermistor" T100000 B4138 ; configure sensor 0 as thermistor on pin temp0
    M950 H0 C"out0" T0 ; create bed heater output on out0 and map it to sensor 0
    M307 H0 A240.3 C608.7 D8.2 S1.00 V24.1 B0 ; disable bang-bang mode for the bed heater and set PWM limit
    M140 H0 ; map heated bed to heater 0
    M143 H0 S120 ; set temperature limit for heater 0 to 120C
    M308 S1 P"temp1" Y"thermistor" T500000 B4723 R4700 C1.196220e-7 ; configure sensor 1 as thermistor on pin temp1
    M950 H1 C"out1" T1 ; create nozzle heater output on out1 and map it to sensor 1
    M307 H1 R2.300 C194.9 D4.24 S1.00 V24.1 ; disable bang-bang mode for heater and set PWM limit
    M143 H1 S280 ; set temperature limit for heater 1 to 280C
    M308 S2 P"temp2" Y"thermistor" T500000 B4723 R4700 C1.196220e-7 ; configure sensor 2 as thermistor on pin temp2
    M950 H2 C"out2" T2 ; create nozzle heater output on out2 and map it to sensor 2
    M307 H2 B0 S1.00 ; disable bang-bang mode for heater and set PWM limit
    M143 H2 S450 ; set temperature limit for heater 2 to 450C

    ; Fans
    M950 F0 C"out7" ; Hotend fan 0 on pin out7 and set its frequency
    M106 P0 S1 H1:2 T30 ; Hotend fan 0 value. Thermostatic control is turned on
    M950 F1 C"out8" ; Layer Fan 1 on pin out8 and set its frequency
    M106 P1 S0 H-1 ; Layer fan 1 value. Thermostatic control is turned off

    ; Tools
    M563 P1 S"standard" D0 H1 F0 ; define tool 1
    G10 P1 X0 Y0 Z0 ; set tool 1 axis offsets
    G10 P1 R0 S0 ; set initial tool 1 active and standby temperatures to 0C
    M563 P2 S"magnum" D1 H2 F0 ; define tool 2
    G10 P2 X0 Y0 Z0 ; set tool 2 axis offsets
    G10 P2 R0 S0 ; set initial tool 2 active and standby temperatures to 0C

    ; Custom settings are not defined

    ; Miscellaneous
    M575 P1 S1 B57600 ; enable support for PanelDue
    M911 S10 R11 P"M913 X0 Y0 G91 M83 G1 Z3 E-5 F1000" ; set voltage thresholds and actions to run on power loss

    ; Filament Sensor
    M591 D0 P7 C"io6.in" S0 E50 L1.25 R25:175 A1


    bed.g

    M561 ; clear any existing bed transform
    G1 Z5 H2
    G30 P0 X2 Y2 Z-99999
    G30 P1 X2 Y229 Z-99999
    G30 P2 X240 Y229 Z-99999
    G30 P3 X240 Y2 Z-99999 S3
    G1 X0 Y0 F5000 ; move the head to the corner (optional)




  • @Vampora said in Duet 3 BLTouch probing issues:

    G1 Z5 H2

    try removing this line
    and adding G28 ; home

    like the guide says

    https://duet3d.dozuki.com/Wiki/Bed_levelling_using_multiple_independent_Z_motors



  • Any why are you measuring 4 points when you only have 3 screws?



  • I started out with 3 and some other that had working configs with the same printer use 4 i guess. I am confused on that one as well.

    @jay_s_uk said in Duet 3 BLTouch probing issues:

    Any why are you measuring 4 points when you only have 3 screws?

    I started out with 3 and some other that had working configs with the same printer use 4 i guess. I am confused on that one as well.

    @Veti said in Duet 3 BLTouch probing issues:

    @Vampora said in Duet 3 BLTouch probing issues:

    G1 Z5 H2

    try removing this line
    and adding G28 ; home

    like the guide says

    https://duet3d.dozuki.com/Wiki/Bed_levelling_using_multiple_independent_Z_motors

    Ill give it a shot.



  • Ideally, you should be aiming to probe close to your Z screws as that's where the adjustments take place.



  • swapping with the g28 still has the 4th probe missing

    G32
    Error: Z probe was not triggered during probing move



  • should i change it back to 3 point to try to figure this out?



  • I would change back to 3 points.
    Just make sure they're in the same order as your M671. So front left, front right and rear middle



  • with the 3 point i still get this:
    G32
    Leadscrew adjustments made: -5.000 -5.000 -5.000, points used 3, (mean, deviation) before (-5.000, 0.000) after (-0.000, 0.000)



  • Can you post your homeall and homez file?



  • homez:

    ; homez.g
    ; called to home the Z axis
    ;
    G91
    G1 Z5 F800 H2
    G90
    G1 X182 Y118 F2400
    G30
    G1 Z2 F200


    homeall:

    M98 P"homex.g"
    M98 P"homey.g"
    M98 P"homez.g"



  • I can't see anything in there that would cause the issue.
    Could you reboot the board and run the probing again?
    Could you also post the updated bed file?



  • Updated bed.g:

    M561 ; clear any existing bed transform
    ;G1 Z5 H2
    G28 ; home
    G30 P0 X2 Y2 Z-99999
    G30 P1 X2 Y229 Z-99999
    G30 P2 X240 Y116 Z-99999 S3
    G1 X0 Y0 F5000 ; move the head to the corner (optional)



  • Rebooted, ran g32:

    G32
    Leadscrew adjustments made: -5.000 -5.000 -5.000, points used 3, (mean, deviation) before (-5.000, 0.000) after (-0.000, 0.000)



  • Nothing else I can add on this one.
    Maybe one for @Phaedrux or @dc42 to comment on?



  • @Vampora said in Duet 3 BLTouch probing issues:

    G31 X-30 Y0 Z0.75 P25 ; Set the offsets for the bltouch

    change to P1000
    P25 could be triggered by interference.



  • @Veti said in Duet 3 BLTouch probing issues:

    @Vampora said in Duet 3 BLTouch probing issues:

    G31 X-30 Y0 Z0.75 P25 ; Set the offsets for the bltouch

    change to P1000
    P25 could be triggered by interference.

    No change
    G32
    Leadscrew adjustments made: -5.000 -5.000 -5.000, points used 3, (mean, deviation) before (-5.000, 0.000) after (-0.000, 0.000)



  • I just want to make sure..... does anyone think it is the bltouch not being v3.1? I'm debating ordering one since I don't have one, but my gut tells me that is not the issue.



  • @Vampora said in Duet 3 BLTouch probing issues:

    M558 P9 C"^io7.in" H5 R1 F120 T6000 A5 S0.02 B1 ; Define the bltouch input on io7.in

    can you change the H5 to H6 and see if the result changes?



  • I actually just tried bumping it to 10 and this is what I got.

    It just changes everything to -10 instead of -5

    M98 P"0:/macros/Probe_Test"
    G32 bed probe heights: -10.000 -10.000 -10.000 -10.000 -10.000 -10.000 -10.000 -10.000 -10.000 -10.000, mean -10.000, deviation from mean 0.000



  • this suggests there is a problem with your bltouch.

    how many probing of the bed does it actually do when you run the macro?



  • It does 10



  • is there an error in the console?

    this suggest that the bltouch is already triggered.
    whats the z value in the ui?



  • What I don't understand is the probes work just fine on my other railcores with duet 2 boards.

    The first time it probes z it will set the z to 0.75 which is the same as my offset. The next time it probes it will say -4.25, and the 3rd will also say -4.25

    When the command is given to raise to Z5 it says 5.75.

    Would a video help shed light on it at all?

    I usually do get random sporadic errors saying that say:

    G29
    Error: Z probe was not triggered during probing move


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