If I may refer back to the original complaint. I too have had six refills create the splitting of a spool. I too thought it was “User Error” until I noticed that in the last several instances the filament became trapped on the side and wedged itself between the spool and the refill to the point of shutting down the AMS. After I released the wedge I found the filament was crossed under it self. Thereby creating a “half hitch” that gets tighter as the spool rotates back and forth in multi color prints. [see images.] This crossing also occurs in my refill between 20-60 % of the spool used. In other words some where well after the spool has loaded and been in use for sometime. This means that the cross over occurred during the creation of the refill. This is therefore a refill production problem. What I have not determined is whether this is a Bambu filament or Amazon filament supplier problem.
BTW I found this also on my mini as well.
All but the light blue are refill spools. Note the uneven shape of the filament in each spool except the light blue. The light blue was a on its own shipped spool. As you can see the gold spool is crossed. both the dark blue and white demonstrated the same problem. In each case I saw the cross over stopped [or paused] the print and unloaded, cleared the cross over and reinserted the filament to resume the prints. That crowning shape suggest that there is other anomalies under the remaining refills. Currently I have six other refills that I have removed the spools and placed in dry boxes that I will try to reclaim at a latter date.
Right now I am having “Dirty micro lidar” problems on 2 of my X1Cs and a mini with a repeating broken filament problem caused by… [You guessed it] a filament cross over jamming problem on the mini AMS. I am woking on 3 possible solutions including the old rewinder with one piece Bambu spools. Of course this relies on getting either of my X1Cs to work. But I am in luck because my old QIDI X-Plus just needs a little bed leveling…