Mesh grid setup



  • I am having a hard time getting the G29 to prob the entire bed. G28 works great and it homes to the center of the build plate. When I run the G29 it does a very small portion of the plate. Config.g:

    ; Configuration file for Duet WiFi (firmware version 1.21)
    ; executed by the firmware on start-up
    ;
    ; generated by RepRapFirmware Configuration Tool on Thu Sep 06 2018 21:21:12 GMT-0700 (Pacific Daylight Time)

    ; General preferences
    G90 ; Send absolute coordinates...
    M83 ; ...but relative extruder moves

    ; Network
    M550 Pe3 ; Set machine name
    M552 S1 ; Enable network
    ;*** Access point is configured manually via M587
    M586 P0 S1 ; Enable HTTP
    M586 P1 S0 ; Disable FTP
    M586 P2 S0 ; Disable Telnet

    ; Drives
    M569 P0 S0 ; Drive 0 goes backwards
    M569 P1 S0 ; Drive 1 goes backwards
    M569 P2 S1 ; Drive 2 goes forwards
    M569 P3 S0 ; Drive 3 goes backwards
    M350 X16 Y16 Z16 E16 I1 ; Configure microstepping with interpolation
    M92 X80.00 Y80.00 Z400 E95 ; Set steps per mm
    M566 X1000 Y1000 Z100 E30000 ; Set maximum instantaneous speed changes (mm/min)
    M203 X6000 Y6000 Z500 E1500 ; Set maximum speeds (mm/min)

    M201 X300 Y300 Z100 E5000 ; Set accelerations (mm/s^2) was 500 you changed it to 300 for stall guard
    M906 X500 Y500 Z500 E1000 I30 ; Set motor currents (mA) and motor idle factor in per cent
    M84 S300 ; Set idle timeout

    ; Axis Limits
    ;M208 X-5.5 Y-10 Z0 S1 ; Set axis minima
    ;M208 X258.5 Y246 Z260 S0 ; Set axis maxima
    M208 X-106:114 Y-110:118 Z0:180 ; Pat added this so home would be center of buildplate

    ; Endstops
    M574 X1 Y1 S1 ; Set active high endstops

    ; Z-Probe
    M574 Z1 S2 ; Set endstops controlled by probe
    M307 H3 A-1 C-1 D-1 ; Disable heater on PWM channel for BLTouch
    M307 H4 A-1 C-1 D-1 ; Disable heater on PWM channel for BLTouch
    M558 P9 H2.5 F120 T6000 ; Set Z probe type to bltouch and the dive height + speeds
    G31 P25 X-31 Y0 Z1.86 ; Set Z probe trigger value, offset and trigger height
    M557 X10:190 Y10:190 S65 ; Define mesh grid
    ;M557 X0:200 Y25:200 S87.5 ; Define mesh grid

    ; Heaters
    M305 P0 T100000 B4138 C0 R4700 ; Set thermistor + ADC parameters for heater 0
    M143 H0 S120 ; Set temperature limit for heater 0 to 120C
    ;M305 P1 X150 T"K" ; Set THERMOCOUPLE parameters for heater 1 X150 is the right channel (terminal block) on the daughterboard. X151 is the right channel.
    M305 P1 T100000 B4138 C0 R4700 ; Set thermistor + ADC parameters for heater 1
    M143 H1 S345 ; Set temperature limit for heater 1 to 345C

    ; Fans
    M106 P0 S0 I0 B0.5 F250 H-1 ; Set fan 0 value, PWM signal inversion and frequency. Thermostatic control is turned off
    M106 P1 S1 I0 B0.5 F500 L255 H1 T45 ; Set fan 1 value, PWM signal inversion and frequency. Minimum Speed is 1/3 aka 87 Thermostatic control is turned on triggered at nozzle temp 45;
    M106 P2 S0 I0 B0.5 F500 H-1 ; Set fan 2 value, PWM signal inversion and frequency. Thermostatic control is turned on

    ; Tools
    M563 P0 D0 H1 ; Define tool 0
    G10 P0 X0 Y0 Z0 ; Set tool 0 axis offsets
    G10 P0 R0 S0 ; Set initial tool 0 active and standby temperatures to 0C

    ; Automatic power saving
    M911 S10 R11 P"M913 X0 Y0 G91 M83 G1 Z3 E-5 F1000" ; Set voltage thresholds and actions to run on power loss

    ; Custom settings
    M591 D0 P5 C3 R10:300 E3.0 S1 ; Duet3D laser sensor for extruder drive 0 is connected to endstop input 3 (E0), tolerance 10 to 120%, 3mm comparison length



  • Here is a video of the probing (there is a joke there somewhere):
    https://www.dropbox.com/s/b009l1dnbz9kwfk/IMG_0005.MOV?dl=0

    These are the warnings that pop up on the screen:

    Warning: Skipping grid point (140.0, 10.0) because Z probe cannot reach it
    Warning: Skipping grid point (140.0, 75.0) because Z probe cannot reach it

    Then…

    Warning: Skipping grid point (10.0, 140.0) because Z probe cannot reach it
    Warning: Skipping grid point (75.0, 140.0) because Z probe cannot reach it
    Warning: Skipping grid point (140.0, 140.0) because Z probe cannot reach it
    4 points probed min error -1.030, max error 0.202, mean -0.400, deviation 0.443



  • Hi,

    Well you changed M208 to put 0,0 at (or near) the center of the bed.

    But the ranges seem a bit odd. X went from 264 to 220, Y from 256 to 228 and Z from 260 to 180.

    But you haven't updated M557 to reflect moving 0.0 to the center.

    Also the S param to M557 is rather large unless you have set it that way for testing. A value of 20 would be better.

    And when setting the M557 X parameter you need to take into account the Z-probe X offset which may limit the possible X range.

    Frederick



  • Hi,

    Just one other thing. It's really just about terms.

    Many folks think of "homing" as moving to 0,0.

    The firmware considers an axis homed when the endstop switch for a given axis is triggered when doing a G1 move for that axis with a H1 parameter.

    When X Y & Z have been homed the printer now "knows" where the print head is located in the three dimensional space bounded by the min/max of each axis.

    At the point the printer is "homed" but that position may or may not be 0,0,0.

    On my printer the homed position of X & Y are at the max limits of each axis. When homing is complete then I can move to 0,0 which is the center of the bed.

    Frederick


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