Brand New PET-G Filament Spool - mis-wound

I purchased a spool of Snapmaker Red PET-G for a project I needed to do. “Life” got in the way as it is prone to do, so it took a few month before I could get to the project. The PET-G sat on a shelf in it’s original box and vacuum seal pack. I opened it and started printing. The first print was great. No issues. The second batch I ran into an issue. If you can see the picture, you will see the PET-G filament is mis-wound on the spool. Somewhere, it is over and under. I was fortunate I was sitting in the room with the printer when I hear the motors whining. It sounds as if they were straining. Sure enough, they were. It was attempting to pull material off the spool, but the material would not come. The material that was next off the spool was literally UNDER other spooled material.

Again, this is a brand new spool, fresh out of the box. The first print was relatively small, but it used about two layers of filament. It worked perfectly for a while. I have to keep pulling out more filament, and then put it back on the roll so the printer can keep going. I have things i need to do, and it is estimated to take another 9 hours to finish.

Have there been any reports of mis-winds on material? I purchased it in December of 2021.

Looks like whoever Snapmaker is paying to produce their filament didn’t do a very good QA job there. Although I haven’t heard other reports of this problem specifically, their filament varies in quality from spool to spool, so I’m not surprised to see this.

Usually this isn’t a problem with the way a spool is wrapped.
It usually happens when there is slack. It loosens the wind and then when it pulls tight it wraps over itself. This can happen when the module goes to home at the end of a job. It can also happen because of the way the stock SM spool holder doesn’t dispense smoothly and evenly.

There are a few ways to prevent this from happening. I added bearings to the stock holder so it rolls easier. Some people have added a larger core for it to turn on. Other’s have printed holders with bearings for it to rest and turn on evenly.

With the current spool, unwind 3 or 4 yards until you know it’s not tangled. If you keep going and still keep finding tangles, than yes, you probably had a bad wind. If not wind it back up keeping tension and make sure you store it with the end taped down or there’s usually a hole or clip on the spool to hold it in place.

I don’t have a v2, so I can’t test this. How well does it handle manually unloading the filament in the middle of a print? Does the run out detection catch it quickly enough, or is that a sure fire way to mess up a print? If it stops, I’d unload it, fix the twist, and reload it.

So far, I’ve never gotten one from the factory like that. It’s always been my fault, or brittle filament that broke.