2y ago

Major issues with klipper and bed levelling

I recently made the switch from the marlin-based stock firmware on my anycubic kobra 2, to klipper. I didn't have issues with bed levelling or first layer on the stock firmware, but I'm having significant issues running klipper. The bed is uneven, the probed mesh shows a deviation of 0.197mm, it was the same when running stock FW+octoprint.

But it seemed to be correcting just fine for this on the stock FW. I got a consistent decent first layer across the entire bed.

With klipper, it's absolutely impossible to get it to correct for this unevenness. Half the bed will get perfect first layer, but then the second half is either way too squished or hardly connecting to the bed. And it's causing further issues as it's also hitting the print when moving, despite having Z-hop of 0.3mm for travel moves.

What the hell is going on? How do I fix this?

8 comments

If you know your deviation, I assume you have a bed probe, right? Are you using your bed mesh? Can you share your start GCode?
- Looks like you have it set to load the profile "default" instead of "bed60"
  Also worth asking, did you have your start gcode set in your slicer previously and if so, did you delete it out of there now that you're using klipper macros?
  For me, in Cura, I simply have START_PRINT and END_PRINT in the start/end fields in the Cura settings. Based on your macro title, it would be PRINT_BEGIN and PRINT_END
  
  Could you also post the [bed_mesh] section of printer.cfg?
- I'm not at my computer now to be able to give specific examples but this most surely sounds like something wrong with the start gcode and klipper not loading your saved mesh before running the print. I'd double check the docs and make sure you have the correct gcode to load your saved mesh.
Is the problem along the X Axis? Maybe you have X Axis Twist. Measure z offset on opposite ends of the bed along X. If they are different you need to enable X Axis Twist Compensation.
- I literally went through this the other day on my franken-ender 3v2. Re-leveling the bed, even tried axis twist compensation.
  I’ve been using Klipper on this thing for a few years and overall it’s been good but finally decided to figure out why I couldn’t get even extrusion across the entire bed even with my klackender probe.
  After days and days of trying to adjust, tighten, loosen screws, redo hot end to be sure it was properly mounted, even axis twist compensation (which it definitely was) I just went back and just took it apart and redid the frame. Making sure it was square, nothing was overtigtened, that the vwheels weren’t binding, tightened just past there being any “slop”, etc.
  Then I removed the compensation hoping that the issue was mechanical and what do you know, it worked.
  I had way over tightened some things obviously and so just going back to the foundation fixed the issue.
  It’s working great now and klipper properly works with the slight warped bed of my Ender.

8 comments