printer fails midprint due to filament "knots"

[Schoepsi 1]

Hey guys.

Lately my prints are failing due to this annoying error and I cant figure out what causes it. Since it didnt happen before Cura 2.6.1 the only guess I can make its anything software sided. I know, it sounds weird that an error like that has something to do with a slicer, but I´m thinking of any retraction settings that changed or something like that. Something that makes the spool lose its tension for a second and cause this "knot"

This error not only occurs on this cheap ass PLA, it also happens on my expensive ones like colorfabb, which u probably know is perfectly coiled up on spool.

From the last 4 prints (between 11h and 32h printtime), 3 failed cause of this error.

Has anyone of you guys an idea on how to solve this problem?

[IRobertI 517]

This is not a software thing. This usually happens if you aren't careful when removing and storing a spool you've already used. It's very easy to have the end of the filament go underneath a coil on the spool and then you have this issue. You might not notice it as first since the filament can keep unspooling normally for a while but eventually it gets too tight and gets stuck. Only way to fix it is to uncoil the filament a bit and find the point where it crosses over and clear it.

[Schoepsi 1]

I´m usually very careful when removing a spool. I´m always making sure that the coil stays tight and use clips so it can´t unwind while stored.

Also, the white spool u r seeing on the foto made a 20hours print before, wasn´t removed and remained untouched until I started a new 11hour print today, which failed after about 5 hours. It´s even funnier that this cheap ass white PLA runs more smooth than the colorfabb one. On my 32hours print with colorfabb I had to jump up every 30minutes cause I was hearing it getting stuck. Sometimes the motors had enough force to unstuck it on their own, but at some point it failed.

here´s a photo of the colorfabb spool. at least optically everything seems fine to me

[fbrc8-erin 270]

It's definitely a filament issue, not software. It can happen when the filament is loose, or if it was spooled badly by the manufacturer.