Line_Purge.cfg

# # # Klipper Adaptive Purging - Line # # #

# This macro will parse information from objects in your gcode and create a nearby purge!
# For successful purging, you may need to configure:
# 
# [extruder]
# ...
# max_extrude_cross_section: 5

[gcode_macro LINE_PURGE]
description: A purge macro that adapts to be near your actual printed objects

variable_adaptive_enable: True      # Change to False if you'd like the purge to be in the same spot every print
variable_z_height: 0.4              # Height above the bed to purge
variable_purge_amount: 20           # Amount of filament in millimeters to purge
variable_line_length: 25            # Overall desired length of purge line in millimeters, around 1/5th of X axis length is a good starting value
variable_flow_rate: 4              # Desired flow rate in mm3/s (Around 12 for standard flow hotends, around 24 for high flow hotends)
variable_x_default: 10              # Default X location to purge. If adaptive_enable is True, this is overwritten
variable_y_default: 10              # Default Y location to purge. If adaptive_enable is True, this is overwritten
variable_distance_to_object_y: 30   # Y distance in millimeters away from the print area for purging. Must be less than or equal to y_default if adaptive_enable is False

### This section is for those who are using Moonraker's Update Manager for KAMP, or want a more verbose macro. ###

variable_display_parameters: True   # Display macro paramters in the console, useful for debugging the SETUP_LINE_PURGE call, or more verbosity.

gcode:

    {% if display_parameters == True %}
      { action_respond_info("adaptive_enable : %d" % (adaptive_enable))  }
      { action_respond_info("z_height        : %f" % (z_height))  }
      { action_respond_info("purge_amount    : %f" % (purge_amount))  }
      { action_respond_info("line_length     : %f" % (line_length))  }
      { action_respond_info("flow_rate       : %f" % (flow_rate))  }
      { action_respond_info("x_default       : %f" % (x_default))  }
      { action_respond_info("y_default       : %f" % (y_default))  }
      { action_respond_info("distance_to_object_y : %f" % (distance_to_object_y))  }
    {% endif %}

    {% if adaptive_enable == True %}
        {% set all_points = printer.exclude_object.objects | map(attribute='polygon') | sum(start=[]) %}
        {% set x_origin = (all_points | map(attribute=0) | min | default(x_default)) %}
        {% set y_origin = (all_points | map(attribute=1) | min | default(y_default)) %}
        {% set x_origin = ([x_origin, 0] | max) %}
        {% set y_origin = ([y_origin, 0] | max) %}
    {% else %}
        {% set x_origin = x_default | float %}
        {% set y_origin = y_default | float %}
    {% endif %}
    {% set nozzle_dia = printer.configfile.config.extruder.nozzle_diameter | float %}
    {% set cross_section = nozzle_dia * z_height | float %}
    {% set purge_move_speed = (cross_section * flow_rate) * 60 | float %}
    {% set travel_speed = (printer.toolhead.max_velocity) * 60 | float %}

    G92 E0                                                                              # Reset extruder
    G0 F{travel_speed}                                                                  # Set travel speed
    G90                                                                                 # Absolute positioning
    G0 X{x_origin} Y{y_origin - distance_to_object_y}                                   # Move to purge position
    G0 Z{z_height}                                                                      # Move to purge Z height
    M83                                                                                 # Relative extrusion mode
    G1 X{x_origin + line_length} E{purge_amount} F{purge_move_speed}                    # Purge line
    G1 E-.5 F2100                                                                       # Retract
    G92 E0                                                                              # Reset extruder distance
    M82                                                                                 # Absolute extrusion mode
    G0 Z{z_height * 2} F{travel_speed}                                                  # Z hop

[gcode_macro SETUP_LINE_PURGE]
gcode:
    SET_GCODE_VARIABLE MACRO=LINE_PURGE  VARIABLE=display_parameters   VALUE={params.DISPLAY_PARAMETERS|default(True)|int}
    SET_GCODE_VARIABLE MACRO=LINE_PURGE  VARIABLE=adaptive_enable   VALUE={params.ADAPTIVE_ENABLE|default(True)|int}
    SET_GCODE_VARIABLE MACRO=LINE_PURGE  VARIABLE=z_height      VALUE={params.Z_HEIGHT|default(0.4)|float}
    SET_GCODE_VARIABLE MACRO=LINE_PURGE  VARIABLE=purge_amount  VALUE={params.PURGE_AMOUNT|default(40)|float}
    SET_GCODE_VARIABLE MACRO=LINE_PURGE  VARIABLE=line_length  VALUE={params.LINE_LENGTH|default(50)|float}
    SET_GCODE_VARIABLE MACRO=LINE_PURGE  VARIABLE=flow_rate     VALUE={params.FLOW_RATE|default(12)|float}
    SET_GCODE_VARIABLE MACRO=LINE_PURGE  VARIABLE=x_default     VALUE={params.X_DEFAULT|default(10)|float}
    SET_GCODE_VARIABLE MACRO=LINE_PURGE  VARIABLE=y_default     VALUE={params.Y_DEFAULT|default(10)|float}
    SET_GCODE_VARIABLE MACRO=LINE_PURGE  VARIABLE=distance_to_object_y     VALUE={params.DISTANCE_TO_OBJECT_Y|default(10)|float}