1. Got a question or need help troubleshooting? Post to the troubleshooting forum or Search the forums!

RoBo3D Autolevel via Mike Kelly

Discussion in 'Mods and Upgrades' started by Mike Kelly, Jun 1, 2014.

  1. Lew

    Lew Member

    Joined:
    Dec 15, 2013
    Messages:
    41
    Likes Received:
    9
    New switches are on their way, but in the meantime with a lot of adjustment and readjustment I have the switches pretty stable.
    However, when I home all, the carriage raises 4mm, drops until the switches open, up again until the switches open, and then drops again. This last drop puts the extruder down hard on the bed, so when the print starts, it is impossible for filament to be extruded.
    Although I have set the Z offset in the starting G code to levels up to 2mm, it continues to try to print with the extruded down hard on the bed. The starting G code looks like this:
    M84 S0 ; Disable motor timeout
    M190 S[first_layer_bed_temperature] ; Set the bed temp and wait for it to heat up
    G28 ; Home all axes
    M109 S[first_layer_temperature] ; Set the extruder temp and wait for it to heat up
    G28 Z0 ; Home Z again in case there was filament on nozzle
    G29 ; Autocalibrate bed
    G1 Z2 ; Adjust Z offset
    G92 Z2 ; Define new Z home

    What am I missing?
     
  2. Mike Kelly

    Mike Kelly Volunteer

    Joined:
    Mar 11, 2013
    Messages:
    6,967
    Likes Received:
    2,275
    G92 Z2 means "Define this position as Z = 2"

    If you use G1+G92 you need to use G92 Z0 to say "define this position as Z=0"

    Or replace G1 and G92 with M565 eg

    Code:
    M565 Z-2.0 ;Define offset as 2, More Negative = further from bed
     
  3. Lew

    Lew Member

    Joined:
    Dec 15, 2013
    Messages:
    41
    Likes Received:
    9
    More Negative = further from bed

    Aha! I used to be a programmer about 700 years ago, but have never before played with G code. I'll try setting the offset to a negative value and see what that does.

    Once again, thanks.
     
  4. Mike Kelly

    Mike Kelly Volunteer

    Joined:
    Mar 11, 2013
    Messages:
    6,967
    Likes Received:
    2,275
    That's ONLY for M565. If you're using the G1 + G92 method it uses a positive value
     
  5. Francois

    Francois New Member

    Joined:
    Mar 28, 2014
    Messages:
    14
    Likes Received:
    4
    hi

    I have remix autolevel of mike (find them here: http://www.thingiverse.com/thing:687502) because i can't find coulpling nuts in belgium.

    the printer seems to work. There are still some particular settings for startup.
     
  6. Marcus Siwica

    Marcus Siwica New Member

    Joined:
    Sep 13, 2014
    Messages:
    9
    Likes Received:
    0
    I upgraded my Robo3d Beta, i use the Firmware R1 with Auto Level and 8mm Rods
    The Problem after the calibration is Nozzle lies on the heatbed. and the z axis down move at the same layer.

    This is my G-Code starting sequece:

    G28 ; home all axes
    G1 Z5 F5000 ; lift nozzle
    G1 Z0.9 ;Adjust Z offset
    G92 Z0 ;Define new Z home
    G29 ;Autocalibrate bed
    G1 Z5 F5000 ; lift nozzle
    M109 S[temperature] ; set the extruder temp and wait
    G28 X0 Y0 Z0 ; Home Z again in case there was filament on nozzle
     
  7. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,853
    Likes Received:
    3,553
    For this version of Marlin you need to include M565 in the startup code to set Z_offset. You would start with something like
    Code:
    M565 Z-1.0
    and work from there. More negative means nozzle is further from the bed, inversely, less negative means closer.
     
  8. Marcus Siwica

    Marcus Siwica New Member

    Joined:
    Sep 13, 2014
    Messages:
    9
    Likes Received:
    0
    with witch G code can i test the new z high on the 9 calibration positions?
     
  9. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,853
    Likes Received:
    3,553
    @Marcus Siwica Do you see the 3rd line of your startup gcode. It is incorrect, it should be M565 Z-1.0. Likely it is probably closer to -0.8 rather than -1.0, but you will need to experiment to find the exact number. It is a single offset for the entire bed. After it is set, the G29 command (the 5th line) creates a map of the 9 points that Marlin uses to tell the printer about any deviation from the offset. This of course is an overly simplistic explanation of what it actually does.
     
  10. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    21,420
    Likes Received:
    7,049
    I did that to two of them. Love it.

    @WheresWaldo is correct. Here is my startup gcode from one of them:

    G28; home all axes
    G1 Z5 F5000 ; lift nozzle
    G28; Home Z again in case there was filament on nozzle
    M565 Z-0.4 ;Adjust Z offset
    G29 ; probe the bed
    M109 S[temperature] ; set the extruder temp (degrees C) and wait

    You may not need that last line, I did since it was taking long enough to do the auto leveling that my temperature preset would fall and trigger a TEMP FALL error.
     
    #130 mark tomlinson, Nov 23, 2015
    Last edited: Nov 23, 2015
  11. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    21,420
    Likes Received:
    7,049
    And you are as Waldo mentioned going to need to experiment to find what M565 Z-XX number works best for you,
     
    #131 mark tomlinson, Nov 23, 2015
    Last edited: Nov 23, 2015
  12. WheresWaldo

    WheresWaldo Volunteer ( ͠° ͟ʖ ͡°)
    Staff Member

    Joined:
    Feb 18, 2015
    Messages:
    5,853
    Likes Received:
    3,553
    @Marcus Siwica He meant to say M565 Z-XX not G1 which is simply a move command.
     
    mark tomlinson likes this.
  13. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    21,420
    Likes Received:
    7,049
    Sure, edit failure :)
    Fixed.
     
  14. Marcus Siwica

    Marcus Siwica New Member

    Joined:
    Sep 13, 2014
    Messages:
    9
    Likes Received:
    0
    the next problem the nozzle(all x Axis components) push the bed at calibration point 2 and 8 too much down.
    I have das wooden plate (heatbed + Glas) on the old rails.
     
  15. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
    Staff Member

    Joined:
    Feb 21, 2013
    Messages:
    21,420
    Likes Received:
    7,049
    It has to push down enough to raise the arm so the Z switches detect it. Make sure the switches are set correctly against the arm and if you are using a spring loaded old-style bed you might want larger/stiffer springs so that it can't push the bed down as easy.
     

Share This Page