New stepper x Stepper buzzes before execution of G28x

[Quailman88]

Hey guys,
I’m running Klipper on a stock Ender 5 with SKR Mini E3 V3 board and Pi 3B. Recently swapped in new steppers:
• X: StepperOnline 17HS15-1504S-X1
• Y: Rattmotor RTM-17HS8401B (running at 1.1A)
The Y axis is perfect. On G28 X it makes a loud rattling noise for the first 3-4 seconds, then moves normally. No rattling on normal G1 moves or manual jogs. Endstop is fine.
I already tried run_current from 1.0 to 1.3A on X, stealthchop_threshold 0 and 999999, driver_TBL 1/2/3, and even replaced the board once. Same thing.
Any ideas what could cause this only on homing for the X motor?

I’m currently at work, I will provide the log and the config later this day, when I’m home.

thank you in advance.

[meteyou]

pls upload your logs + a video with sound.

can you move the pulley from the X stepper (i think the ender 5 is cartesion, so only one stepper is working for 1 directory) with your hand without any issues (so no blocking points an a hole turn, only the normal stepps are feelable?

[Quailman88]

Hi again,
thanks for helping me.
here are the requested files:

klippy.log
printer.txt

video is too large for upload so i uploaded it on youtube here

ive played with various different [tmc2209 stepper x] setting but it had no effect whatsoever.

note that any other movement i perform with the x axis is totally normal. This only occurs during homing x.

*edit:

I've triple checked belt tension. It's now fairly loose and i can move it by hand without issue when the printer is off.
After i changed the Y-axis to linear rails, i now did the same with the x axis and installed the new stepper motors. I througly cleaned the rails in isoprophyl bath in my ultrasonic cleaner and re-lubricated them before installation.
I've also made new belts and when the pulley is off it moves very smooth.

So i dont think pulley tension is a problem.
as i have mentioned before, whenever i execute any movement (G1 or move to position) it works without a problem - no sound, good and smooth movement.

[meteyou]

sry for the delay. I think the sound is your Z-axis. you have safe_z_home in your config and your bed is just at the bottom and it cannot move down for 10mm before it homes the x axis:

[safe_z_home]
home_xy_position: 110, 110 # Change coordinates to the center of your print bed
speed: 50
z_hop: 10                 # Move up 10mm
z_hop_speed: 5

pls touch your x and z stepper to feel, which one is making this noise at this time.

[Quailman88]

Hi,

no worries. So i didnt change a thing in my .cfg and for whatever reason the problem stopped. Maybe it hat to do with Klipper learning about the motor. (I read that somwhere in the documentation).
Because i printed several parts with it in the meantime. Whenever i started a Print-Job, the problem also didnt occur.
Now when i home the axis (G28) it works without issue...
I have no clue whatsoever. Perhaps the motor had to break in, or i had a minor dust particle blocking the Rail.
No clue at all.
However it is, the Problem is gone now.

[Quailman88]

ive made some more changes to my printer - i found out you were right again. it was the Z-Stepper that caused the problem.
i have a 2mm pitch lead screw installed and... long story short, i found out it was the z-hop that caused the problem.