Homing Issues



  • Hi,

    I'm having some very weird issues when homing my machine - and it's a 50/50 chance each time i go to home, i suspect i have a wiring issue ( bad connector but where? )

    So when i do a all home the machine will move to the X Max axis ( this is where my endstop flag is ) and then go to Y - Min axis
    now this is where the 50/50 chance comes to play. It will either move to the center of the bed and probe it ( like it should ) or the machine will crash back into the X Max axis and the machine is trying to move forward to the Y+ while still crashing into the X-Max the whole time.

    I then turn off the machine and then turn it back on and then it's perfectly fine and homes and does an initial probe like it should.

    I don't think it's an endstop fault - i think might be a dodgy stepper motor or connector but how can i tell?
    are there any debug logs that will monitor the process of my home all to see what is failing?

    here are snippets of my config.g

    G90                                                 ; Send absolute coordinates...
    M83                                                 ; ...but relative extruder moves
    
    M667 S1                                             ; Select CoreXY mode
    
    ; Drives
    M569 P0 S1                                          ; X Dir Physical drive 0 goes forwards
    M569 P1 S1                                          ; Y Dir Physical drive 1 goes forwards
    M569 P2 S1                                          ; Z Dir Physical drive 2 goes forwards
    M569 P3 S1                                          ; Ex1 Dir Physical drive 3 goes forwards
    M569 P4 S1                                          ; Ex2 Dir Physical drive 4 goes forwards
    M350 X16 Y16 Z16 E16:16 I1                          ; Configure microstepping with interpolation
    M92 X80.00 Y80.00 Z3200.00 E406.00:406.00           ; Set steps per mm
    M566 X800 Y800 Z60.00 E600.00:600.00                ; Set maximum instantaneous speed changes (mm/min) Jerk
    M203 X25000.00 Y25000.00 Z300.00 E9000.00:9000.00   ; Set maximum speeds (mm/min)
    M201 X4500.00 Y4500.00 Z120.00 E7000.00:7000.00     ; Set accelerations (mm/s^2) Acceleration
    M906 X1300.00 Y1300.00 Z500.00 E1300.00:1300.00 I30 ; 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 X310 Y305 Z300 S0                              ; Set axis maxima
    
    ; Endstops
    M574 X2 Y1 S1                                       ; Set active high endstops
    
    M671 X1:1:310:310 Y1:305:305:1 P0.5                 ; adjusting screws at Front left (7,30), Rear Left (7,359) rear right (320,359), Front Right (320,30) thread pitch 0.5mm
    
    ; Z-Probe
    M574 Z1 S2                                           ; Set endstops controlled by probe
    M558 P5 F500 I1 T6000 A1                             ; Probe Mode NPN NO P=Mode5 F=Speed it probes T=Move speed, Inverted Sig, A= test 1 times,
    G31 P100 X35.0 Y20 Z0.63                             ; Probe Position and Height was.098 before i changed with simplify3d at 200
    M557 X0:310 Y0:305 S42.5                             ; Define mesh grid
    
    ; Heaters
    M307 H0 B0 S1.00                                    ; Disable bang-bang mode for the bed heater and set PWM limit
    M305 P0 T100000 B4138 R4700                         ; Set thermistor + ADC parameters for heater 0
    M143 H0 S120                                        ; Set temperature limit for heater 0 to 120C
    M305 P1 X200                                        ; Configure PT100 for heater 1
    M143 H1 S280                                        ; Set temperature limit for heater 1 to 280C
    M305 P2 X201                                        ; Configure PT100 for heater 2
    M143 H2 S280                                        ; Set temperature limit for heater 2 to 280C
    
    ; Fans
    M106 P0 S1 I0 F500 H1 T45                           ; Set fan 0 value, PWM signal inversion and frequency. Thermostatic control is turned on
    
    ; Tools
    M563 P0 D0 H1                                       ; Define tool 0
    G10 P0 X15 Y0 Z0                                     ; Set tool 0 axis offsets
    G10 P0 R0 S0                                        ; Set initial tool 0 active and standby temperatures to 0C
    M563 P1 D1 H2                                       ; 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
    
    ; Automatic saving after power loss is not enabled
    
    ; Custom settings are not configured
    
    ; Miscellaneous
    M501                                                ; Load saved parameters from non-volatile memory
    T0                                                  ; Select first tool
    
    

    Homeall

    ; homeall.g
    
    G91 ; relative positioning
    G1 Z5 F6000 S2 ; lift Z relative to current position
    G1 S1 X400 F4000 ; move quickly to X and Y axis endstops and stop there (first pass)
    G1 S1 Y-400 F4000
    G1 X305 Y5 F4000 ; go back a few mm
    G1 S1 X345 Y-375 F360 ; move slowly to X and Y axis endstops once more (second pass)
    G90 ; absolute positioning
    G1 X155 Y152.5 F4000 ; move probe to bed center
    G30; probe the bed
    G29 S1 ; loads mesh template
    G1 X0 Y0 Z2 F4000 ; return to home position and 2mm higher than the surface
    


  • your homeall script is not for a corexy machine.

    corexy needs seperate moves for x and y.

    like this

    ; homeall.g
    ; called to home all axes
    ;
    ; generated by RepRapFirmware Configuration Tool v2.1.8 on Sun Jan 26 2020 10:08:37 GMT+0100 (Central European Standard Time)
    G91 ; relative positioning
    G1 H2 Z5 F6000 ; lift Z relative to current position
    G1 H1 X235 Y-215 F1800 ; move quickly to X or Y endstop and stop there (first pass)
    G1 H1 X235 ; home X axis
    G1 H1 Y-215 ; home Y axis
    G1 X-5 Y5 F6000 ; go back a few mm
    G1 H1 X235 F360 ; move slowly to X axis endstop once more (second pass)
    G1 H1 Y-215 ; then move slowly to Y axis endstop
    G90 ; absolute positioning
    G1 X15 Y15 F6000 ; go to first bed probe point and home Z
    G30 ; home Z by probing the bed

    ; Uncomment the following lines to lift Z after probing
    ;G91 ; relative positioning
    ;G1 Z5 F100 ; lift Z relative to current position
    ;G90 ; absolute positioning


  • Moderator

    @aceycv8 said in Homing Issues:

    G1 S1 X400 F4000 ; move quickly to X and Y axis endstops and stop there (first pass)
    G1 S1 Y-400 F4000
    G1 X305 Y5 F4000 ; go back a few mm
    G1 S1 X345 Y-375 F360 ; move slowly to X and Y axis endstops once more (second pass)

    The X movements in all of those commands is positive.

    And as Veti says, you will need seperate moves for each axis, so on the last move, both axis will stop once either of the limit switches is triggered regardless of the position. So one or the other axis could be in the wrong place.



  • Thanks for the tips guys - didn't know that about Homing a coreXY - if i read the Wiki properly i would have 😕 i copied my config from my Cartesian and it's caught me out!

    I will see how it goes

    Thank you



  • I still had the same issue,

    Then i realized while i'm playing with my machine i have a macro that calls M564 S0 H0 so i can move my machine around without being homed for testing as this is a fresh build i'm ironing out the bugs.

    so therefore when i use that marco it never resets when you do a call home thus the X axis is always crashing as the machine doesn't know it's position.
    to safeguard myself i've put M564 S1 H1 in the start of my homeall file

    Thanks for your assistance


  • Moderator

    @aceycv8 said in Homing Issues:

    M564 S0 H0

    I think that this combined with the double positive X axis moves I mentioned above would make the machine think that you were way out of the build volume when homing.

    Glad you got it sorted.



  • @aceycv8 said in Homing Issues:

    i copied my config from my Cartesian and it's caught me out!

    please use the configurator to create the initial configuration.


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