Intermittent nozzle scraping/dragging on build plate during pre-print sequence #533
Description
Is there an existing issue for this problem?
- I have searched the existing issues
CrealityPrint Version
6.3.1.3548, 7.0.0.4127
Operating System (OS)
Linux
OS Version
Ubuntu 24.04
Additional system information
No response
Printer
Creality K1-MAX
How to reproduce
Slice a model using Creality Print.
- Start the print job.
- Observe the pre-print preparation (homing, leveling, or moving to the purge line start).
- Intermittently, the nozzle moves diagonally across the bed while being pressed against the surface.
Actual results
I am experiencing a critical issue where the nozzle occasionally scrapes the build plate during the pre-print preparation phase. This behavior is inconsistent; it doesn't happen every time, but when it does, it leaves deep scratches (triangular patterns) on the plate. It seems like the printer is performing a diagonal move across the bed without sufficient Z-axis clearance.
Actual Behavior: The nozzle drags across the bed, creating deep scratches in a triangular pattern. This suggests a Z-axis positioning error or a missing "lift" command in the start G-code.
Expected results
The nozzle should lift to a safe height before performing any horizontal movements across the build area during the startup sequence.
Project file & Debug log uploads
Creality Print.zip
Shit happened twice: in V7 is around debug_Wed_Feb_04_10_42_08_1465361.log (textured plate) and V6 is around debug_Tue_Feb_03_14_07_17_1121685.log (smooth plate)
Checklist of files to include
- Log file
- Project file
Anything else?
I have performed full calibration and Z-offset adjustment after changing the plate. Since the issue is intermittent, it feels like a software/G-code logic bug rather than a hardware leveling issue.
After another scratch on the bed, I noticed that this only happens after interrupted printing. If printing was interrupted while the printer was preparing to print (not during the printing process itself), this issue occurs. Also, the first “movement” of the head is accompanied by an abnormally loud clicking sound.