I’m pretty sure I wasn’t the only one! Yes! Its when it homes, and usually when parking. I know its not an alignment issue because it prints flawlessly now, tech support keeps wanting me to align the toolheads.
When mine parks from the homing position its as if it moves down the Y axis too fast and then doesn’t move across the X axis enough to park the toolhead correctly.
I agree, I think its a tension issue that we can’t fix (at least I can’t fix)… I stopped responding to my tech support email but might keep pushing the issue, its a huge annoyance to have to manually release the toolhead so often.
I did a quick search in ChatGPT, please forgive me, I’m not the owner of a U1.
It should be done in the printer configuration.
To set or limit the maximum printing speed in Klipper + Fluidd (e.g., for an XY printer), this is done in the firmware configuration file printer.cfg — here you define the limits for speed (max_velocity), acceleration (max_accel), and optionally “junction deviation”.
1) Overview: Key Settings
In Klipper, there are three central parameters for motion control:
Parameter
Meaning
max_velocity
Maximum speed (mm/s)
max_accel
Maximum acceleration (mm/s²)
max_accel_to_decel
Max acceleration when transitioning from acceleration to deceleration
junction_deviation
Controls corner behavior/velocity transitions
2) Configuration in printer.cfg
Open Fluidd (the printer’s web UI)
Go to Configuration → Printer Configuration
Find or add the [stepper_x], [stepper_y], [stepper_z], and/or [printer] sections
Example for X/Y axes:
[stepper_x]
...
max_velocity: 300 # Max speed of X-axis (mm/s)
max_accel: 3000 # Max acceleration (mm/s²)
max_accel_to_decel: 3000
[stepper_y]
...
max_velocity: 300
max_accel: 3000
max_accel_to_decel: 3000
I received this email from tech support earlier today, with a link for a temporary firmware update to fix the (homing parking issue). @simon_zhi Can I post the link here?
*Hello,
Thank you for your feedback.*
*
This issue may occur if the toolhead changer does not retract far enough during homing, causing the limit signal not to be detected.*
*
Please try using the temporary firmware to see whether the problem persists.*
I just received my U1 and been having a similar issue. My problem seemed to have gone away after I applied the provided grease to the three magnetic points on the tool head. The tool heads came with grease already applied on them and when I first installed them I accidentally wiped some of the grease off.
I found another reason for the tool head mounting failing. I was getting a tool head error every time I was trying to start a print job. When I fixed the loose cover on my extruder the check tool head procedure completed and my print job started. Still no sure why it coming loose.
Yea the same thing happened to me, sometimes when you have parking issues that front plate could get knocked off or loosened depending on the severity of the misalignment. Have you updated to the latest firmware?
1) Overview: Key Settings
2) Configuration in printer.cfg