RE: First layer calibration after assembly
It seems that your bed was not plane and/or not leveled (not parallel to the X and Y axes). Try tu adjust it with a steel ruler and check the parallelism to the axes with a gauge or optical (maybe also with a paper) controll of nozzle/bed distance at 9 points).
Also important is a correct Z-Level fineadjustment and a clean bed (no dust and oil..). Try to clean the bed with soap and hot water, maybe also Isopropanol. For PLA the smooth sheet is the better option.
Statt zu klagen, dass wir nicht alles haben, was wir wollen, sollten wir lieber dankbar sein, dass wir nicht alles bekommen, was wir verdienen.
RE: First layer calibration after assembly
I link this article so often I should pay a commission:
After you do this, post a picture of your calibration square (or circle).
RE: First layer calibration after assembly
@karl-herbert
Thanks for your advice, I'm trying it.
RE: First layer calibration after assembly
While it is printing, slowly lower the Z (make it more negative) until the strands blend together.
In your picture, they are like strings laid side by side.
Done correctly, they will partially merge and peel up as one surface when you are done.
RE: First layer calibration after assembly
I finally solved the problem, it is about the height of the nozzle. I tried to troubleshoot the problem by recalibrating XYZ for many times, but I failed. However, I began to have the idea of my problem, and I started to adjust the height of the nozzle, I just followed the assemble instruction to adjust it from the left corner to the right corner, and make sure the the parallelism (the x-axis and the bed).
Finally, I realise the problem is about first layer, and solve it by referring a very nice article.
3D Printing First Layers Problems
https://3dnewb.com/3d-printing-first-layer-problems/
It introduces a model to adjust your bed leveling. It is a must keep item!! really.
https://www.thingiverse.com/thing:34558 (please refer to the article for the description of testing).
Hopefully, it can also help others who also assemble by yourself. It is not a easy thing to figure out the problem by a new 3D printer joiner.
RE: First layer calibration after assembly
@robert-rmm200
thank you robert! your hints of height helps me a lot!