Printer Model: Adventurer 3 (Heavily Customised)
MCU / Printerboard: BTT SKR Mini E3 v3
klippy.log
klippy.log (1.9 MB)
I’ve been trying to get this working consistently for days - the first time I home it works, the next time I try it the X/Y axis go in the wrong direction and I get a print-head crash.
I’ve implemented the recommended macros + homing overrides and am still having no luck. 
Here is the printer in action:
[homing_override]
set_position_z = 5
gcode =
G0 Z7
G28 X0 Y0
G0 X110 Y67
G28 Z0
Your homing override doesn’t contain any macros.
Ah good point - I had been pointing to these:
HOME_X
HOME_Y
HOME_Z
but have tried so many things I prolly lost myself.
A couple of things jump out at me:
homing_speed (100 for x, 75 for y) is high. I normally run them at around 25 (mm/s)driver_sgthrs values are pretty high (which means they can be overly sensitive), especially since you are running with 0.8A run_current. I’ve set up StallGuard on four printers now and I’ve never needed a value above 75 for driver_sgthrs.How did you come up with your sensorless homing values?
I think your problem is that the threshold values (driver_sgthrs) are so sensitive that the subsequent homing operating gets a false sense and causes the toolhead to move to the right, causing the head crash and buzzing.
Could you:
run_current when homing to 0.5A.homing_speed to 25.driver_sgthrs to 64.Once you’ve done that, test the sensorless homing for the X & Y axis separately and determine the best driver_sgthrs by running the axis homing twice until it works reliably both times. If it crashes when reaching 0, add 10 to the value, if it detects it properly, then reduce the value by 10. When you’re close, change the difference value to 5 until you’re satisfied.
Good luck!
Thank you for the info - i’ll give your suggestions a try - I’m new to sensorless homing and there dont seem to be any good guides on it.
The official docs have an extensive guide on how to configure sensorless homing in Klipper.
https://www.klipper3d.org/TMC_Drivers.html#sensorless-homing
That’s what I followed - most klipper guides are great, this one imo is not as helpful.
I’m still haviong issues with the Homing going the wrong direction:
[homing_override]
set_position_z: 5
gcode:
HOME_X
HOME_Y
G1 X110 Y67
G28 Z0
[gcode_macro HOME_X]
gcode:
{% set HOME_CUR = 0.500 %}
{% set driver_config = printer.configfile.settings['tmc2209 stepper_x'] %}
{% set RUN_CUR = driver_config.run_current %}
# Set current for sensorless homing
SET_TMC_CURRENT STEPPER=stepper_x CURRENT={HOME_CUR}
# Pause to ensure driver stall flag is clear
G4 P2000
# Home
G28 X0
# Move away
G28
G1 X5 F1200
# Set current during print
SET_TMC_CURRENT STEPPER=stepper_x CURRENT={RUN_CUR}
[gcode_macro HOME_Y]
gcode:
{% set HOME_CUR = 0.500 %}
{% set driver_config = printer.configfile.settings['tmc2209 stepper_y'] %}
{% set RUN_CUR = driver_config.run_current %}
# Set current for sensorless homing
SET_TMC_CURRENT STEPPER=stepper_x CURRENT={HOME_CUR}
# Pause to ensure driver stall flag is clear
G4 P2000
# Home
G28 Y0
# Move away
G90
G1 X5 F1200
# Set current during print
SET_TMC_CURRENT STEPPER=stepper_x CURRENT={RUN_CUR}
and I have no idea why.
I’ve tried lower values in the past without luck. This at least works sometimes.
I just watched your video, and it’s not doing what you described. What’s happening the second time you home is the diag pin is triggering instantly for both X and Y, and the printer is then trying to move to the middle of the bed to home Z. It looks to me like you need to slow down both X and Y, and better tune the sgthrs values so they’re not overly sensitive.
OK, I think Im getting somewhere after lowering homing speeds to 25 and dropping driver_sgthrs to 64 - Im still finding the “Homing override” confusing, tho as it seems to ignore my Move X/Y command and tries to Home Z at X0/Y0.
[homing_override]
set_position_z: 5
gcode:
HOME_X
HOME_Y
#Home Z
G1 X110 Y67 F1500
G28 Z
You would need to provide a new log file in order for me to offer any other help.
[gcode_macro HOME_X]
gcode =
{% set HOME_CUR = 0.500 %}
{% set driver_config = printer.configfile.settings['tmc2209 stepper_x'] %}
{% set RUN_CUR = driver_config.run_current %}
SET_TMC_CURRENT STEPPER=stepper_x CURRENT={HOME_CUR}
G4 P2000
G28 X0
G28
G1 X5 F1500
You’re homing X in this macro, then telling it to home everything. Remove the G28 from this macro.
[gcode_macro HOME_Y]
gcode =
{% set HOME_CUR = 0.500 %}
{% set driver_config = printer.configfile.settings['tmc2209 stepper_y'] %}
{% set RUN_CUR = driver_config.run_current %}
SET_TMC_CURRENT STEPPER=stepper_x CURRENT={HOME_CUR}
G4 P2000
G28 Y0
G90
G1 X5 F1500
You also need to fix this macro. It should move to Y5, not X5 at the end.
Thanks, some dumb mistakes there - I really should not try to configure something new when Im tired. 
Thank you both (@jakep_82 @mykepredko ) for your help - it’s now working consistently! 
I also made a tweak to my homing override macro to raise the Z gantry before homing:
[homing_override]
set_position_z: 5
gcode:
G1 Z+25 F1000
HOME_X
HOME_Y
#Home Z
G1 X110 Y67 F1500
G28 Z
G1 Z+25 F1000
It lives! 
Great job.
I look forward to see what you come up with.
Cheers, My entire Klipper config and custom PCB’s are now in my GitHub Repo.
However, I haven’t gotten around to publishing my printed parts yet.
Edit: I’m out of replies for the day:
Cool. Keep us updated as to your progress.
