So I’ve found on several occasions that I have filament snap/break while respooling.
I had sevaral rolls of old PETG that I tried to respool on to AMS friendly spools when I found that they would snap after 5-10m. I couldn’t really tell whether they snapped while being rewound, or were parhaps already snapped/broken on the spool which only became evident when respooling. These spools of PETG where probably 5-6 years old and have been heated to ~70c multiple times to dry over that period. They must have had around 300-400g left on them. They did seem to be very tightly wound (or perhaps the filament slightly stuck to itself giving that appearance). I ended up throwing these away as the issue was so frustrating.
I’ve just recently tried to respool some reasonably new ASA and had a similar issue of the filament snapping. I’d recently dried it at 70c for 12+ hours and then allwed to cool.
Now I’m concerned that drying the filament (expansion/contraction with the hot and cool cycles) is actually causing it to fracture on the spool.
Has anyone else had a similar experience? I’m using one of the cylindrical food dehydrators for drying. Now considering one of the Creality Space Pi Plus dryers instead.
I had an issue with Esun Petg where I was getting way too much stringing, I then got the Space Pi Filament dryer from Creality and dried my filament for 12 hours as I left it out for to long, then a few more hours with every print. After a few days when I tried to print anything, all my prints would be so dry, colour would be matt and it was meant to be a bit shiny and they would be brittle, like layer adhesion was terrible, I could peel away layers of the print, and I’m sure it’s because of overdying filament
Plastics contain plasticizers that contribute to their plastic properties. Over time, plasticizers can “cook off” and the plastic becomes less “plastic” . It’s why old plastic sometimes gets brittle and crumbly.
For the 5-6 year old plastic, maybe this explains it. But not the ASA. I don’t think drying explains that. If one bout of drying kills the plastic, I’m thinking it was defective to begin with. You should be able to dry many times without a problem. I routinely do this, since I don’t try to keep stored filament dry enough it’s ready to print without another round in the dryer. Every time I swap something out of the AMS, what goes in goes through 24 hours of dryer, first. I probably have some rolls of PA, PETG and ASA/ABS that have been through my dryer a dozen times.
It was room temperature, perhaps 19-20’C, not cold enough that I would expect the ASA to be brittle. The only other thing I can think is that a combination of the original crappy cardboard spool and my rather basic food humidifier dryer in which the spools lay on their side just didn’t dry the filament much beyond the top few layers.
Regards old plastic getting brittle I’d thought the main cause of that was UV exposure. I wonder whether some plastics like PETG are more susceptible to degradation from drying than others like PLA.
With my old PETG spools, I had dried them in the kitchen oven several times in the past, temperature control at the low end isn’t brilliant using that method. I used a thermometer to get the temp correct but it’s quite possible they could have been overheated at some point. they almost felt like the layers of filament has very lightly fused together, or the filament had contracted after drying and pulled itself tighter onto the spool - perhaps to the point of fracturing.
Think I’m going to buy a Space Pi Plus to replace my old dehydrator dryer. Perhaps that’ll be a bit more of a satisfactory solution, better airflow etc. Honestly storing and drying filament is one of the most irritating parts of 3D printing if you don’t print a significant quantity but like to have lots of options on the shelf. I was using vacuum bags but have more recently switched to cereal containers. Nothing seems to be completely airtight. If only they could develop filaments that don’t absorb water. Perhaps a very fine coating of something that acts as a moisture barrier - that would be amazing, particularly for PET and Nylon.
Vacuum bags and Tupperware-style containers do not have hermetic seals. They may leak slower than other options, but they still leak. And there’s really no good/direct way to know if filament is still dry enough without printing and finding out. It can actually be more time consuming, effort wise, than just assuming the filament needs to be dried and drying it each time. And with that philosophy, storing it “dry” isn’t that important.
This is my approach.
I don’t respool, so I wouldn’t be as likely to notice a break, but now I have a printer with an AMS that has to pull back the filament, if it breaks I will know it. So far, after a year of printing, I’ve only had a filament break once, and it was PLA I knew was kind of wet (PLA gets brittle when it gets wet).
You could soak your filament in WD40. Everyone uses it as a lubricant, but it was originally invented to keep Atlas Missile components from rusting in their silos. The “WD” stands for “Water Displacement”. Apparently it took them 40 tries to get the formula right.
Please note, I’m not talking about TPU, it’s different from other filaments when it comes to drying requirements. It may actually NEED drying every time, depending on where you live.
Drying other filaments damage them?
Normally, no. If you are using the filament frequently it will be used up before there are any issues as it should only need drying a few times. You will not have to dry it often enough for the “cooking off” mentioned earlier to be a problem. If you store it in a vacuum seal bag (which is how you should store it), you don’t have to dry it every time you take it out and use it. Especially if it goes right back in after use.
If you print some of the center spool desiccant holders and put desiccant in them when putting it in the bag to go in the bag, it definitely shouldn’t need drying every time.
Now for how drying it can damage it.
Drying it too long every time.
Drying it at higher than the recommended temperature.
Drying it too often.
A combination of the above.
Last, some filaments have a shelf life. You can find a topic on that regarding PLA by searching the forum. I linked a video on that. You extend the shelf life by not letting them soak up a lot of moisture in between use and drying them reasonably.
If you want to know if there is humidity penetrating the bag after sealing, you can include either a small hygrometer, or a moisture detection strip where the colors of the strip change as humidity increases . Strips are single use. Once a color change occurs at one level, it will not go back if humidity decreases. They are used to let you know what the maximum humidity reached is.
It was. And it seemed so outlandish, I assumed it would be instantly recognized as such. But I added a happy face just in case.
But just to be sure, even though it should not need to be said (remembering that Aluminum Ladders come with instructions that include “don’t rest against power lines”), do not use WD40 lubricant on your filament to keep it dry.
You know you have now started a new stream of misinformation.
The internet will ignore your second post, you will be the legend that was found legally liable for damaging millions of 3D printers.
I suggest that you should spray your body with WD40, so the lawyers can’t grab hold of you
I thought it was but there are people of all skill levels here and some might not get that. Sure as the sun rises, someone would cite that on a post about print problems and say they followed all the directions and even sprayed the filament with WD-40 and their printer still caught fire…
. It’s why old plastic sometimes gets brittle and crumbly.
