Inconsistent extrusion in specific area with growling printer

[Skydev]

Greetings!

I have encountered an interesting problem on a new X1C.

Several test prints with PLA were fine, and, afterwards, 2 or 3 ABS prints came out perfect.

But, afterwards, a strange problem started happening, and it looked like the first layer was squished too a little too hard for some objects.

However, after a closer observation, it seems, that in specific area (corner) the extrusion is unstable, and the printer gives growling sound when the problem manifests.

Interestingly enough, it seems to affect the print less and less at higher layers, where it eventually disappears completely. But it is really troublesome on lower layers.

The model printed is this one, with added 2 loops 10 height skirt just in case.

It would be very nice if you could help investigate and solve the problem, because, I am afraid that the printer would soon start barking at me rather than just growling.

Flow calibration and heatbed levelling were activated for the print.
The plate is Textured PEI which the printer came with.

The photos of the issue are attached below.

Also, I have recorded a video of the problem with the growling:

20250414_000027.mp4

(especially noticeable starting with 0:33)

20250414_000512.mp4

(especially noticeable starting with 0:10)

[user_2427585868]

My thought would be

A.) Tramming issue.
B.) Temperature issue.

Would you happen to have a inferred thermal gun? If it were me, I’d heat it up to the printing temp you used for this filament with a piece of paper over the build plate and then take thermal samples. That corner might not be heating as well as the rest and in such case, I’d raise the bed temp until that corner hit the sweet spot the rest needed to adhere right.

Otherwise, maybe tram the bed over again, and purposely make that corner just a little bit higher? If that is the “not live” corner, like the A1 has one unadjustable corner, maybe make that corner higher by making the other 3 corners lower. Add an extra quarter turn or eighth of a turn to all the other screws.

[JonRaymond]

Check to make sure the lidar on the head isn’t hitting bed alignment mod you have in the back right corner.

If you remove the bed mod does the printed area get better?

[Skydev]

Thank you for your suggestions.

As for the Shifty - it does not touch lidar (and actually, the problem manifestates far away from that place), but removed it just in case.

About the temperature - it is pretty even (and interestingly, exactly matches what is written on screen when heating up, and when heated it is 88 in hot spot when 89 is displayed on the screen).

(The photo was done without a build plate, so that reflectivity would not affect the result)

Recalibrated the whole thing again, will see how it goes pretty soon.

About the tramming… well, I have re-installed the bed (because did thermal photo), so will see how it goes after it was removed, reinstalled, and relevelled.

Maybe indeed it shifted for some reason and levelling data was way off.

[Skydev]

Well, thank you guys for help!

Anyway, after the build plate (not bed, lol) re-installation and enabling levelling for each print (even if it was not touched because ABS is extremly easy to slide off after PEI is cooled down) the problem went away and have not reappeared for entire day yesterday after numerous prints.

As a result, the prints kept resulting like the right one:

Maybe enabling levelling for each print may be a bit too much, but I’d rather spend several extra minutes per 2.5-hour print than get squished stuff on the left.

I also removed right Shifty so that rather to be safe than sorry - although it seems to be physically impossible for lidar to touch it, it indeed maybe sometimes got hit and affected calibration or something else, so yeah, out.