Standard PLA Filament breaking

Whenever I do a print, all is well until it finishes and sits for a bit (like overnight or long prints). The filament breaks after the spool and is super brittle from the extruder to the start of the roll. So I have to break off the brittle length, empty the bowden tube and reload filament for each print. This only seems to happen with the 3D Printing Canada Standard PLA Warm White (1.75mm). I have the standard black and grey, but they don’t break.
I’ve noticed this becoming more regular in the past few months, to every time in my last few rolls. Was there a change in the filament?
Please advise.

Your filament has most likely absorbed water.

There is the option of drying it out and, to avoid this issue in the future, I recommend placing the filament spool in a plastic bag with desiccant when you’re not using it.

I have my rolls sitting on a shelf with no issues with them sitting there over time.
Would there be a solution for my case, running an overnight print where the roll will be on the printer for a couple hours after the print is done? These are printers at my work so I can’t just wake up and put a bag over the roll.
This hasn’t been an issue until the last couple months. Been fine in the same place for a couple years now.

Honestly, I’m surprised you haven’t had problems before this. Maybe something changed where you store the filament (it’s not clear if they’re at work or at home) - especially in terms of the HVAC and/or humidity.

It shouldn’t be a problem to run a print and then bag the left over filament with desiccant a few hours later.

I do find that PLA is relatively more sensitive to moisture than ABS and PETG and the changes do take place over months (not days or weeks), which is similar to what you’re seeing. I haven’t see any difference in terms of colour or brand, but I don’t tend to run many different colours at one time (right now I just have two different PLA colours active) and try to run a reel to completion as much as possible.

Regardless, why don’t you try to dry out the white PLA that you’re having trouble with in an oven, as suggested in the link I sent? The results should be interesting and help point you in the right direction.

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I agree with @mykepredko My printers run a lot and the next roll of filament to ut on it is always in the dryer beforehand, especially for PETG but for PLA too. After it’s dried the brittleness should go away, I say should because there are other processes that can make the plastic brittle like UV exposure or some chemical is absorbed into it but it’s very common for it to just be water.

Thanks for the advice, Guess I’ll get some dryers

It’s the time of year when there’s a lot less “conditioned” air flowing, either hot or cold… which also usually means no humidity control in lots of cases. Spring and fall are always more moist indoors as a result. Dryers would be great in your case I think. I’m super lucky that my printers are in my server room, which tends to be super dry as I let it run hot and exhaust it often. 15-20% relative humidity in server room == happy filament without a dryer!

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You can try just a warm oven for a couple hours…or a food dehydrater if you have one.

Are North American ovens to hot to heat the water out? Drying at too high a temp. isn’t good for the filament is it? Europeans do this but it seems their ovens have a lower bottom temperature then ours.

Our ovens have 100°f temp for the lowest. but an oven with an incandescent bulb will reach 100-120 with just the oven light going. That’s how I sued to proof bread.

I seem to have a lot of problems with 3D’s Value PLA either right out of the box or after 3 hours in a dehydrator. Started at 190/40 went up to 230 80 with all the steps between and found the best results about 210/ 70 or sometimes 215/70. This is Not my go too filament. If I have a poor print I immediately switch brands and almost always have a good print. The 3D guys are great. But their Value plus need help.

Going back to my original issue: filament between the roll and bowden tube absorbing moisture while idle after a print finishes. Then cracking and breaking up.

Note: this is only happening to 3D’s Standard PLA Warm White, I have black and grey standard that doesn’t break up.

I think getting a filament dryer isn’t going to solve my issue, there will still be an exposed section of filament from the dryer to the bowden tube that will break up.

Would it work to modify a filament dryer to directly feed into the bowden tube? Has anyone been successful in doing something like this, or has the same issue that can advise me with a different solution?

usually, if I dry my filament before I put it on the printer I have no problems until the roll is finished. I put it away in sealed containers in between if I’m not going to sue it all up.

For my recent roll:

I came to work and started a 12+ hr print (fresh roll, just unpacked from vac-seal/silica bag). I came back the next morning, print is finished but the filament is all broken and brittle from the moisture. I can’t come into work in the middle of the night to pack-up the filament roll.

Should I be looking into a bigger solution, full printer enclosure that has dry filament storage as well?

An aside question, does moisture effect the integrity of printed parts? Or just the filament?

The fresh form of the package roll was probably wetter than it would have been stored on a regular shelf in a home. The little gel packages will be able to absorb water from the air inside the package but they are not enough to get the moisture out of a roll of filament, unfortunately. I’ve had rolls like this too from different makers arrive this way.

I see,
So ideally, when I get a roll, I should be drying it out before using/storing it?
And because I have been using fresh “damp” rolls, they won’t last long before getting brittle. Correct?
Also, I should be “re-drying” the roll before storing after a print?

What is the humidity level where you print. I have had several rolls and never had a problem with moisture in the filament. I print in a spare bedroom where the humidity is low so maybe that is why. I also store my open rolls in a plastic bin with a dollar store (actually a couple of dollars) moisture absorbing capsule in it. You can see the water in the capsule that has been collected.

There are numerous examples of these on You Tube and how to make them.

I have no idea what the humidity is, filament and printers are in the office at my work. There’s a moderate ventilation system, but it gets pretty warm and humid when the sun’s out.
I’ve only just experienced this issue over the past 3-4 months, that’s why I’m looking into this. otherwise I’d assume it was a bad roll or two.