Print failure : is it my end code ?

[mbunjes]

Today I printed a tall and thin object which took almost the entire height of my Trident.
When the print finished, the toolhead didn't move back like it normally does. Instead the bed tried to move up all the way, destroying the printed piece.

Why did it do that?

here's my end code , could somebody please take a look ?

 

[gcode_macro PRINT_END]
#   Use PRINT_END for the slicer ending script - please customise for your slicer of choice
gcode:
    # safe anti-stringing move coords
    {% set th = printer.toolhead %}
    {% set x_safe = th.position.x + 20 * (1 if th.axis_maximum.x - th.position.x > 20 else -1) %}
    {% set y_safe = th.position.y + 20 * (1 if th.axis_maximum.y - th.position.y > 20 else -1) %}
    {% set z_safe = [th.position.z + 2, th.axis_maximum.z]|min %}
    
    SAVE_GCODE_STATE NAME=STATE_PRINT_END
    
    M400                           ; wait for buffer to clear
    G92 E0                         ; zero the extruder
    G1 E-2.0 F3600                 ; retract filament
    
    TURN_OFF_HEATERS

    UPDATE_DELAYED_GCODE ID=filter_off DURATION=180
    
    G90                                      ; absolute positioning
    G0 X{x_safe} Y{y_safe} Z{z_safe} F20000  ; move nozzle to remove stringing
    G0 X{th.axis_maximum.x//2} Y{th.axis_maximum.y - 2} Z50 F3600  ; park nozzle at rear
    M107                                     ; turn off fan

 

Edited July 21 by mbunjes