Yet another retraction tower. Not really any different than most others. I designed it to run the tuning_tower command in Klipper to tune firmware retraction. Slice with a 0.2mm layer height,  zero infill, 2 perimeters, 4 bottom layers and 5 top layers. The Klipper command for tuning firmware retraction is as follows, replace what is in the brackets with your desired parameter to tune (and remove the brackets).

TUNING_TOWER COMMAND=SET_RETRACTION PARAMETER=[retract_speed, retract_distance, unretract_speed, unretract_extra_length] START=[one increment (step_delta) less than your actual desired start value] SKIP=1 STEP_DELTA=[the quantity of how much you would like to change your parameter with each band of the model] STEP_HEIGHT=5

I have the commands set as macros with my baseline settings for different material types.

One of the macros I use:

[gcode_macro Tune_PLA_Retraction_Speed]
gcode:
 TUNING_TOWER COMMAND=SET_RETRACTION PARAMETER=RETRACT_SPEED START=25 SKIP=1 STEP_DELTA=5 STEP_HEIGHT=5