I have a nearly full spool of Bambu ABS Silver filament. It’s been in a cabinet at about 10% humidity for about a year. I took it out to put it in a dryer and find that it snaps very easily if I just bend it. I’m wondering if this is normal? I don’t have enough experience with ABS to know how brittle it is normally.
I dried it at 70C for 24 hours and it’s just as brittle as it was. Is ABS normally brittle on the spool? I can bend it and simulate the AMS path and think it might be ok but I don’t want to have to disassemble my filament path. It doesn’t take much to snap it.
If I wrap it around my wrist (7" circumference) it won’t snap. But if I wrap it around the thickest part of my thumb, it snaps.
Oh well, as soon as the AMS loaded it to identify it and retract it, it snapped inside so I had to disassemble the AMS. It got a spring cleaning since I was in there but it looks like my ABS got too brittle from age to use. It appears that ABS has a shorter than normal storage life, even if kept well.
Take note that any section that has already been passed through the AMS will have indents from the feed rollers and this can cause brittleness. If a spool is having issues, trim off this section and this should hopefully solve your issue.
Ha, yea, no way I can do that with mine. It has apparently died of old age… I just threw it away, argggg, 800g of it. Obviously, I don’t use it or need it often but I will be mindful that if it sits around for a year or so, it can die of old age. Maybe the silver version is more susceptible, who knows. Anyway, now I have a new empty refillable spool.
Not trying to one-up anyone but my VERY oldest spool which is Hatchbox ABS is still pliable today in 2025 (just tested it again now before posting) and I bought it way back in 2018! Yup, 7 year old ABS and it is still flexible enough to wrap around my finger.
So I think it depends on the manufacturer and what additives each uses.
FWIW, I keep all my non-PLA filaments in “semi-sealed” containers (they have a sealing lid but it is not very airtight) with spool mounted desiccant holders (maybe 50g of desiccant each). RH meter says usually about 20-25%. So not stored in open air but also not delicately stored either.
As to why I still have 7 year old filament laying around - it’s because I hardly ever print ABS. Back when I bought it I was a n00b and also there weren’t so many choices then. I printed a few things, found I hated the fumes (even with an open window) and so…7 years later I still have about 300ish grams left.
But can confirm Hatchbox ABS (at least the formulation they made 7 years ago!) can stand the test of time. In my experience though, Hatchbox has always made quality filament and justifies its higher than average cost. YMMV.
I’m having the exact same problem with the same Bambu Silver ABS, and my spool is only two weeks old, so it’s brand new, not a stale one. I followed the manufacturer’s drying recommendations using my AMS pro 2 and store it in a dry box at 10% humidity. Despite printing on an enclosed P1S with a popular 5 star model, the result was so brittle it shattered immediately when I tried to put it together. I tried a different model and the result was the same.
It’s alarming that your experience from a year ago is identical to what I’m seeing with a fresh spool now. @RobH2 did you ever find a solution or identify the cause? Knowing if it’s a chronic issue with this specific color or something else would be a huge help.Thanks!
Once printed the filament shouldn’t be “brittle” as the moisture has been removed. You might double check that you are using the right filament profile. Can you link to the model that you printed and have issues with?
From your picture you are probably running into more of an issue of the threads being too tight and binding. It also seems like both your wall count and infill seem low. Threads will put a lot of pressure on the weakest part of the print which is the adhesion between layers. This is generally where you will see parts fail regardless of filament type. It is a limitation of current FDM technology.
I appreciate your insight about thread binding and layer adhesion, that makes perfect sense.
Here’s what’s puzzling me: I used exact profiles to print the same models in Generic PLA+ with perfect, strong results. That success is why I moved to ABS. In fact, as shown in the picture, the structural rod on the ABS version is so weak I can snap it with my fingers like a pretzel, while the PLA+ version is impossible to break.
Given that the model and settings are proven to work, what ABS-specific adjustments would you recommend to overcome this brittleness?
I would start with more walls and higher infill number.
That said, your part shouldn’t be that brittle. Are you pausing the print at all or printing a bunch of parts at the same time? The reason I ask is if the part has time to cool without new plastic added (while the head is off printing the top layer of another part) it can shrink (as ABS does) and there will be a larger gap (and a weakness) when the next layer is applied.
