preventing filament tangles

I’ve lost several prints due to the filament tangling in the reel. I suspect it is from retraction back to the tightly wound reel (in my case Overture, 6.5mm @ 25mm/s on my Bowden tube E5+).
My 1st thought is to put the reels on a ball bearing roller but making the reel more friction-less is likely not going to solve the issue. Does anyone here have ideas? As you can see it’s not a fresh reel and I didn’t recently change filament. It worked for several large prints then got tangled.

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Thank you,

If you buy a spool and the filament is tangling, then it is in 99.9% of all cases your fault.

You must not (never ever) let got the end of the filament. If so it may look like you got it without any harm, but once it escaped, it got tangled in most cases. The end digs in and it will resurface after causing a knot.

Rule #1 is to always fixate the filament roll end. Use the holes in the spool to lock it in. Use a clamp to fixate it to the spool.

If the filament breaks for some reason you cannot prevent tangling unless you guide it directly next to the spool through a ptfe pipe.

If the end escaped for some reason, get some tape and tape the entire spool down. Now unwind the end at least 10m, before you rewind it. The tape will prevent the section, where the filament end got below the filament on the spool, from moving further in. Filament knots are nasty.

You may loose the end on a new spool, but the knot may move undetected for hours and even prints. Retracts are loosen the filament on the spool and the knot can move further. But in the end a print will fail as some point.

It is a myth that filament gets tangled, when the spool got winded unevenly. That is impossible. The filament gets produced in one go onto your spool, so it is impossible to get tangled. The only way this is happening at the factory, when the worker is removing the filament and the end got loose. This should never happen, as the worker knows the problem and the spool gets fixed by quality control or sold as “b-ware”. So gettng a tangled spool from the factory is highly unlikely, unless the end was already loose in the package.

Just take a spool of sewing yarn as an example. There is no way you can tangle it up, unless you let the yarn end go loose. Since those spools are small and the material soft this happens only sometimes, but it happens in the same way as with filament.

There is no way a printer can tangle filament on its own.

thank you, great answer:)

Totally agree with @Geit. I’ve used quite a few different makes of filament & never had a tangle. Oh, I had a tangle 1 time, but I absolutely know it was my own fault. I fixed it & everything went fine after that.

I remember going through that phase of my 3d learning curve. I was not careful and out of 4 rolls of filament I had 3 crossed and I thought it was the manufacturer’s fault. Since then I have been very careful and have learned how to free a snarl if I get one from broken filament.

For the spools on the printer I have a pretty nice working solution:


I installed a PTFE tube mount under the spool holder. It not only prevents filament from hopping sideways off the spool during retract, it also prevents the filament from tangling in case it slips away or breaks at the direct drive, which can happen, when the printer is not in use for some time.

Quite nice to have especially when swapping filament colors mid print. You unload and let go, load the new and done. No need to take care of the end. The PTFE tubing keeps it in place and under control.