Ahh damnit. When your in a hurry and this happens -_-
Never done any printing myself and joined because I plan to in the future. As a welder by trade I can relate to tangled spools of wire 
@MadMetalManiac74 hehe Iam working in a wire company. Know that too 
Could have been my fault though ^^
I had a 2kg roll of 1.75mm PETG that kept doing this. Ruined several large prints. Ended up re-spooling the entire thing :@
#thestruggleisreal
@Justin_Morel
as I mentioned I work at a wire-factory. How can this even happen!? This was my 3rd time now. On this spool it might have been because it unravelt itself once. But on the other two the filament was never taken off of the printer. Not sure what the are doing in production. Maybe on packaging someone drops them or something and the spool it on by hand or what? You can overlapp the wire but it will unravel under a certain ammount of load. This was a knot or something lol.
@VolksTrieb As I’m sure you know, it’s physically impossible to put a knot in a spool without letting go of the free end at some point. So SOMEBODY at SOME POINT let it unravel. The big, reputable filament vendors like esun are very consistent about controlling the free end so this doesn’t happen from the factory. It’s USUALLY the end-user’s fault. But cheaper filament vendors may not always control the ends.
@Ryan_Carlyle
Thats why Iam asking ^^
@VolksTrieb yea. It must have unraveled at some stage. That is what happened to my spool of PETG. I thought I had UN spooled it enough to remove the knot, but clearly not. In the end I re-spooled the whole thing end to end (a complete headache as you can imagine) but had to be done.
I had this a week ago. Most annoying. Managed to unwind enough of it to get to the twist and respool without losing the job. Lucky I was sitting near that machine and heard it pull the spool of the holder thought something broke.
Happened to me more than once, usually with bargain brand filament.
@funinthefalls I don’t think the price of the filament has much affect on this particular problem. Unless maybe some cheap spools don’t have those little holes to keep the end when not in use.
Doh!
I have had tangles where it was not crossed the way you have it but wound in such a way that the filament was barried under other filament somehow which caused the same result as a tangle.
@Guillaume_Lavoie thats possible. Most certainly because its wound too tight
That can also happen when you don’t secure the end of the filament. The first couple of wraps loosen and then the end of the filament goes underneath one of the loops and then as the filament gets pulled by the extruder it causes what you see in the picture. Vader is right in that if you do have the filament “loose” on the spool that it will tend not not cause a tangle but you would be baby sitting the spool the whole time.