Hey. On my X1C with PLA Matte/PETG HF/and TPU I often get these “strings” on the first layer. It’s usually fine but every now and then it’ll cause a failed print.
Would this be called “stringing”? Usually happens either when there’s an internal bore, when the first layer is done and the printhead moves to wipe, or after the auto flow calibration when the head moves over to print
That’s on Bambu’s PETG HF fully dried for like 3 days straight lol, and manually calibrated [both Flow Dynamics and Flow Rate] just last night. Machine was recalibrated a few days ago as well.
What’s that called, is that normal, and how can I minimize this?
EDIT: Oh no [it’ll be fine]:
I would refer to that as oozing. It is material coming out of your nozzle during a travel (where, I assume, the extruder is not being commanded to extrude)
Is your retraction on?
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If the flow/PA cals are good, it’s not dry. For whatever reason, your dryer didn’t do the job. I print a lot of PETG. Fully dried it does not ooze or string.
Unfortunately, the forum no longer appears to let you embed a larger image that can be seen by clicking the inline image in a post. So I can’t zoom in to look more closely. But this booger is pretty big and it looks exactly like what a moisture-induced ooze should look like.
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Thank you. I guess it’s possible it’s not dry. This would have been dried for about 3 days in my creality dryer [But at 60c while Bambu recommends 65c for their PETG-HF] and then vac sealed with desiccant AND THEN stored in a weathertight container that also has desiccant lol. The hygrometer inside the vac seal bag read 10 and the 2 hygrometers inside the weathertight container also reads 10.
I’ll have to try drying my PETG-HF at 65c from now on.
Would you call my filament “oozing” or “stringing”? I think I’d call it “oozing” but I’m a 3d printing newb.
Thank you. I didn’t change any retraction settings so the retract is set to whatever the default is. Any idea what I should set the retract settings to?
You can still right-click it and hit “open image in new tab” fortunately.
I can’t account for why the filament appears to still be “wet” in spite of your drying efforts (which certainly seem like they should have been sufficient). But based on the pictures, that’s the only explanation I can come up with. That booger I posted a screen snip of, above, isn’t caused by the extruder pushing filament. At least, IMO, its appearance is 100% characteristic of oozing caused by filament moisture. Stringing is a side effect of oozing. Fixing the ooze should fix the string.
Do you have an AMS (the enclosed one)? Are you in a particularly humid environment?
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Ok. I ended up buying an AMS 2 solely for the drying function/to get to the bottom of this. There have been a few PETG HF (and one Matte PETG by California filaments) that I dried previously for an absolute minimum of 8 hours and sometimes up to 3 days in my Creality drier. They then each got vac sealed immediately with a hygrometer/desiccant in-spool container. Then those vac sealed bags got stored in an airtight container that also had desiccant/2 hygrometers. Stored no longer than 2 months. All hygrometers would always read “10” within minutes IIRC.
It looks like my crealitiy drier either can’t get as hot as it claims or there’s something wrong with it. Or due to the Creality dryer not having a sealed door and living in New England maybe that’s just not a good dryer for me. IDK.
After drying with the AMS 2 I don’t have perfect prints now with PETG HF, there is still a little stringing/oozing, but it’s definitely much better now!
I think overhangs look better as well.
Flow and/or PA need a tiny bit of tweaking.
The driest PETG will still string a bit if there is even the slightest excess flow.
Not sure what I’m seeing here…
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Hmmmm I’m not sure as I don’t have the original file. But it looks like that’s bridging that didn’t bridge too well:
Yeah, that was my guess. Except it looks like underextrusion, where other areas look like you’re pushing just a tiny bit too much plastic. Did you slice with bridge flow set to a really low value (vs. the default of 1.0)?
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