Secondary needle calibration

Macros
1

Hi everyone.

Some time ago I decided to convert my 3 axis dispensing robot to Klipper control. Previously I had to use a “teach pendant” to set up the program, which was time inefficient and inaccurate. Now I just need to create a program with G code from CAM and CAD.

However, I had a problem with the accuracy (axial symmetry) of the dispensing needle. I wanted to solve it this way:
Video

Thanks to user @gaolst I have a workable solution. Here is the original thread with the macro by @gaolst:
Original thread

Here is my version of the macro:

[gcode_button calibration_X_button]
pin: !PG12
press_gcode:
  {% set position = printer.motion_report.live_position %}
  SET_GCODE_VARIABLE MACRO=set_nozzle_offset VARIABLE=x0 VALUE={position.x}
  {action_respond_info("X-press-trigger X: %.2f "% (position.x))}
release_gcode:
   {% set position = printer.motion_report.live_position %}
  SET_GCODE_VARIABLE MACRO=set_nozzle_offset VARIABLE=x1 VALUE={position.x}
  {action_respond_info("X-release-trigger X: %.2f "% (position.x))}

[gcode_button calibration_Y_button]
pin: !PG13
press_gcode:
  {% set position = printer.motion_report.live_position %}
  SET_GCODE_VARIABLE MACRO=set_nozzle_offset VARIABLE=y0 VALUE={position.y}
  {action_respond_info("Y-press-trigger Y: %.2f "% (position.y))}
release_gcode:
   {% set position = printer.motion_report.live_position %}
  SET_GCODE_VARIABLE MACRO=set_nozzle_offset VARIABLE=y1 VALUE={position.y}
  {action_respond_info("Y-release-trigger Y: %.2f "% (position.y))}

[gcode_macro do_calibration_move]
description: Do calibration moves in X and In Y
gcode:
  {% set microstep_count = 150%}
  {% set microstep_size_x = 0.05 %}
  {% set microstep_size_y = -0.05 %}
  {% set microstep_speed = 100 %}
  {% set move_speed = 3000 %}
  {% set z_jump = 10 %}
  SAVE_GCODE_STATE NAME=calibrate_1_state
  G90
  #Go to starting position for X calibration
  G0 X90 Y250 F{move_speed}
  G0 Z7 F{move_speed}
  G91
  #Do microsteps in X
  {% for step in range(microstep_count) %}
    G1 X{microstep_size_x} F{microstep_speed}
  {% endfor %}
  #Ok we finished X, now we need to return to start position 
  #but need to jump over trigger
  G0 Z{z_jump} F{move_speed}
  #Go in reverse to starting position for Y calibration
  G0 X{microstep_size_x*microstep_count*(-1)} F{move_speed}
  G90
  G0 X68 Y224
  G91
  G0 Z-{z_jump} F{move_speed}
  #Do microsteps in Y
  {% for step in range(microstep_count) %}
    G1 Y{microstep_size_y} F{microstep_speed}
  {% endfor %}
  G90
  RESTORE_GCODE_STATE NAME=calibrate_1_state
  
[gcode_macro set_nozzle_offset]
description: Fetch stored X and Y and set offsets
variable_x0: 0.0
variable_x1: 0.0
variable_y0: 0.0
variable_y1: 0.0
gcode:
  {% set me = printer["gcode_macro set_nozzle_offset"] %}
  {% set dx = me.x0 - ((me.x0 - me.x1)/2) %}
  {% set dy = me.y0 + ((me.y1 - me.y0)/2) %}
  {action_respond_info("dX: %.2f, dY: %.2f" % (dx, dy))  }
  G1 Y {dy} # Move needle to the centre of the optical gate "Y"
  G92 Y218.85 # Setting the correct coordinate relative to the machine axis
  G4 P500
  G91
  G0 Y7
  G90
  G0 X90 Y250 
  G1 X {dx}  # Move needle to the centre of the optical gate "X"
  G92 X94.15 # Setting the correct coordinate relative to the machine axis
  G4 P500
  G91
  G0 X7
  G90
  G0 Z50
  G0 X152.1 Y168.3

And here is a video of the calibration:
Needle calibration video

Z-axis calibration is not part of this macro. This is solved via PROBE.

I hope it helps to someone as much as it helped me :slight_smile:

Tony

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