Spool holder being dragged towards the printer
I'm fairly new to 3d printing and can't quite figure out if I have a potential problem here. So I've got a Mini, primarily print with Prusament PLA, and I am using the supplied spool roller. I haven't had any issues as of yet but I've noticed that sometimes the printer is essentially dragging the spool and holder towards itself. My worry is that I'll start to have failed prints due to the printer not being able to pull in filament when needed.
I understand that the filament on the spool should be fairly tight so that it doesn't get too loose and becomes tangled/knotted but I'm not sure if this is an indication of a temperature/moisture problem or if it simply comes down to my tabletop being to smooth.
Do I have a potential problem here or do I simply need to come up with a means to keep the spool holder in place?
RE: Spool holder being dragged towards the printer
I put silicone feet on my spool holder. You might be able to find something like this locally: Silicone feet.
I purchased them at Walmart and Home Depot in my local community. They are adhesive on one side and have antiskid surface on the other.
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Chuck H
3D Printer Review Blog
RE: Spool holder being dragged towards the printer
Could be that your surface is just smooth and those little pieces of rubber do not have enough friction. Anti-skid feet is not a bad idea. Those bearings inside spool holder should spin to allow smooth rolling, check is they are not stuck by any chance.
And hey ... you have a 3D printer! 😆 There are thousands of search results when you type "spool holder" on any popular 3D prints hubs, find one you like and try it. Here: https://www.yeggi.com/q/spool+holder/ or take it as a challenge and design your own 😉
RE: Spool holder being dragged towards the printer
I did a bit of experimenting and I'm starting to think that this spool of filament might be the problem. The spool holder seems to have good traction on the table surface and the spool rotates smoothly and easily. It might be noteworthy that I've only had the printer for a month or so and I haven't used an entire spool of filament yet. All the spools of filament I have are Prusament PLA.
The spool of filament I was using when I noticed this has been used the most and I've probably used 66% of it. I feel like I've noticed this before but I can't remember if has been only with this spool of filament. When the filament is being pulled off this spool it is under a lot of tension and almost sounds like it is stuck together and being pealed off... I can hear a slight cracking sound... if that makes any sense. Yesterday the printer actually pulled the spool completely off of the holder... luckily I was there when it happened so it didn't mess up the print.
I later put on a different spool of filament, one that is two or three weeks newer and a lot less of it has been used. Using this spool of filament the problem isn't there... the filament pulls off of the spool smoothly and the pealing/cracking sound doesn't happen.
So is this sticking of the filament somewhat normal or should it never happen? Is this possibly a function of the fact that I've used more of the filament on the problematic spool? As you get closer towards the center of the spool is it pressed tighter against itself than on the outer edge causing it to be compacted more... resulting in something happening chemically causing it to stick together?
I ultimately see two possibilities here:
1) Under no circumstances should the loops of filament be sticking together. There is ultimately a problem with the filament itself or how it was spun onto the spool causing each loop to stick to the ones below or adjacent to it.
2) This is perfectly normal as you use more of a spool and I just need to permanently attach the spool holder to something so it can't move. I think this is unlikely as I can't imagine Prusa would provide this type of spool holder if this was normal.
RE: Spool holder being dragged towards the printer
It neither normal nor desirable. Unfortunatley PLA has a very low glaas transition temperature (material starts to soften), it will melt on in car on a sunny day. Is it possible that the spool was subject to 50°C +?
The crackling sound you can hear may be boiling off of absorbed water.
Too much back tension to the extruder drive gears is obviously undesirable. I think you should source another roll of filament.
RE: Spool holder being dragged towards the printer
I realize this is an older post, but I have had the same problem with Elegoo PLA Pro. But only once the roll reached the point of being about 80% empty. Going to switch to a fresh roll of PETG that I have on hand and see if it solves the problem. It did not occur to me that this might be due to a problem with the filament, since it was fine most of the way through the roll. Until I read this post I assumed it was a problem with the spool holder (which, imho, is not impressive. The newer Mini+ comes with plastic bearings, not metal)
Thanks for addressing this.
RE: Spool holder being dragged towards the printer
In order to solve this completely, use a spool holder that has a ptfe tube connection fixed to the spool holder itself. That way the only dragging force is between the spool and the entrance on the spool holder, which is fixed in place relative to the spool.
Example:
https://www.printables.com/model/320766-bowden-feeder-for-prusa-mini-spool-holder