I’ve had lower qualities on my print lately so did some maintenant on the printer. The nozzle (Hardsteel .4mm) was covered in what I assume is melted PETG. So much so that it was stuck and I had to heat the nozzle to pull it out.
I couldn’t find any mention of that anywhere. Is this a result of a lack of maintenance ?
I’d appreciate any insight on what went wrong.
Happens on my A1 min as well, no sign of it (yet) on my relatively new H2C.
PETG clearly sticks quite well to steel; I wonder if it’s wicking upward via the small gap between the hotend and the silicone sock?
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It seems to be the issue indeed, but I’m perplexed by the lack of result I find online about this issue.
How are you cleaning the nozzle on your A1 and how often ?
PETG loves to pick up water. When moisture content gets too high, uncontrolled extrusion driven by the steam and possibly filament rheology changes from the moisture cause it to curl somewhat as it exits the extruder. Bits can curl enough they reach back up and touch the extruder and stick.
Then other fun things can happen which it looks like you are on the edge of. Search for “encased extruder”. Here’s a post with a photo and not the worst example posted here.
Even more fun is the filament strand after it reattaches to the extruder can act much like a lava tube where the outside hardens some but inside it’s just a channel to pump molten filament up and around the extruder. There have been amazing examples of that posted here.
It happens a fair amount with PETG and really seems to happen with filament with too high of moisture content.
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Petg often leaves a white residue too I wonder if that’s burning on contact with the nozzle, though don’t these have silicone covers on them ? It’s possible that it’s stringing and catching on the nozzle as it moves
I’ve had the same issue, I use petg a lot. I’ve tried cleaning it, but was a hassle and couldn’t fully restore the print quality.
Ultimately I just replaced the nozzle
I need to make it clear that I’m completely new to 3D printing so I’m not giving learned advice here, only heard advice. I have about 180 hours on my H2C printing with PLA only on downloaded, as well as self-created models. I’m fortunate to live 2 minutes from COEX 3D. Not only are they a print farm, but they also make and sell their own filament. The people there are great at answering questions.
I was in there two weeks ago to purchase some PET-G. The guy actually made me a little afraid to use it, haha. His warning was that if you don’t adjust your settings correctly, it can clog up your nozzles and may potentially force you to purchase new ones.
Aside from ensure your settings are correct, he said that it’s necessary to either leave the door open or take the top off if you’re using a closed printer because PET-G cannot print correctly in a closed case. I don’t know if this is part of your problem, but thought I would share. He also told me that Orca Slicer (free software) has all the settings in it for their filament and it’s based off of Bambu Studio. It looks very similar, so there’s no learning curve there. However, if you still want to use Bambu Studio he said you can go to MakerWorld and search for the COEX 3D crab. There is one for each of the filaments they make. You can open that in Bambu Studio, save the profile and then recall them for your own project.
Of course the caveat is that you’re using their filament. I don’t have any experience on how much variance there is in between filament manufactures. Maybe it matters, maybe it doesn’t. Either way, I’m still hesitant to put the PET-G in. I’ve used their PLA without issue, but I think for anything else, I’ll likely order it from Bambu to start with, and use their profiles until I’m comfortable with it.
I think he may be saying “don’t run petg on the pla profile”
Just put the generic PETG profile and give it a go they should have put the temperature ratings on the filament too
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This guy is full of BS.
- Are they actually making their filament on premises, or are they buying bulk spools and respooling it in 1kg lots for retail sales?
- Modern PETG-HF is not fussy material at all. I never print with the door open and there is testing that shows PETG prints are stronger with the door closed, and even moreso with mild chamber heating. I’ve been running the Biqu chamber heater in my X1 for months and have never had a clog with PETG
- If their filament is that fickle that they need to give customers extensive warnings, lest it forever clog their nozzles, the filament kinda sucks.
- I’m questioning their ability to unclog nozzles, too.
- There’s nothing stopping them from being able to share a print profile for their filament in Bambu Studio, rather than steering customers to a different slicer.
All told, if I heard all that from someone I wouldn’t buy their filament again.
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There was a “white residue” inside the silicone cover, but I attributed that to the cover reaction to heating. But I didn’t see any residue on the nozzle itself.
I keep my PETG in the AMS 2 Pro but I also have an AMS HT that show 30% humidity when it’s not running.
Do you suggest I should run the PETG from the HT running at lower humidity ? Or does it just mean that I should use newer desiccant (mine hasn’t changed colour yet)?
Thanks for the informations and the detailed explanation, it looks like you identified the issue correctly.
On a side note, I didn’t manage to clean the nozzle completely. I decided to use a new one to avoid the PETG sticking to itself again. I’ll see if I can salvage it somehow but this is not the primary issue.
I don’t know the details of the AMS HT but drying is a slowish process. If filament is spending much time at 30% humidity it will tend to move to whatever moisture content that corresponds to. My experience with PETG HF is that’s too high, though. Just putting the spool in a lower humidity environment to print won’t have enough time to make much difference in filament humidity. Standard AMS units don’t really dry filament though that can happen over time but it’s very inefficient. It takes heat and the new AMS units to do much drying. But I’m not familiar with the HT. Maybe it dries?
To be clear, the color change isn’t really a go/no go change. You’d need to check the specs for your desiccant to see where the color change occurs. If you’re lucky that will be where filament goes from printing well to not printing well but it may even be likely it’s not.
If your AMS is at 30% humidity, my advice would be to change that desiccant and re-dry the filament before it goes back in. In my experience 30% humidity is too high especially with PETG. Desiccant can also act as a water source if your filament is more dry than the desiccant. You don’t want that.
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I thought the whole point of the HT was to dry filaments. The premade setting to dry the PETG-HF takes 12hours, but I don’t know how effective it actually is.
Anyway, I ordered new desiccants and I’ll be changing the bags with printed container to fill the AMS has much as possible. According to my research, this should lower the humidity quite a lot already. And going forward I’ll monitor the humidity instead of the beads, it does make more sense.
He sounds like an old school 3d printer type from the bad old days of the late 2010’s! I have found PETG to be very forgiving in my P1S. I was long careful to keep the lid propped open, but I have found even with the door and lid both shut, PETG prints without issues for me – from Sunlu, Bambu, Tecbears, Elegoo, Creality, all fine.
I’ve certainly never had to replace a nozzle, even when I was using a Monoprice bedslinger. (I had every other possible problem with that machine, but not nozzle clogs!)
Give the PETG a go. I think you will be pleasantly surprised. It’s my go-to material.
I’m just not familiar with the HT and if it dried or not. It sounds like it does dry.
The humidity in the enclosure will tell you how effective it is. The humidity in a sealed bag or box at room temperature with no desiccant will give you numbers possibly easier to compare.
If you used silica gel beads desiccant then there’s a good chance they are “renewable” by heating in an oven with good temperature control. The manufacturer should say somewhere in their product literature.
Fresh/dry silica gel beads will definitely lower the humidity but there are considerations if you are putting them in a dryer. Silica gel can act as a water sink or source depending on what’s in the enclosure and how dry it is compared to the silica gel beads. The museum/archival storage industry uses silica gel a lot in environment-controlled cases to both humidify and dehumidify. You can buy them preconditioned to specific humidities.
To not hinder filament drying, the silica gel needs to be kept at a lower humidity/moisture content than the ultimate humidity/dryness level you want to dry to or else it can be a water source instead of a sink. If it gets to a higher moisture content/humidity than where you want your filament, it can limit how dry you can get your filament or make the dry take longer as you dry the silica gel too. The other thing is if your silica gel gets to a humidity/moisture content that is higher than as low as the dryer can pull on its own, the dryer will be trying to dry the silica gel too and that will decrease drying effectiveness.
In active dryers, you can add silica gel as long as you keep it dry - more dry than the dryer could dry it alone - or else it’s just adding water load. Similar with AMS units with desiccant. The silica gel gives water more places to go as long as it’s dry and will help extend desiccant life, but needs to be regenerated/replaced when the factory desiccant pouches get replaced. Replace the factory desiccant without regenerating/replacing the silica gel and the silica gel turns into a water source and shortens the life of the pouch desiccant.
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They produce their own filament on site and run a print farm. From what I’ve seen, every manufacturer has variables in their product that if not tuned correctly could result in failed prints. If that weren’t true there would be universal print profiles and you’d never have to change anything. The guy I speak with is their modeler and operates the printers, at least on Fridays. He never said “lest it forever clog their nozzles”, he said “you can clog your nozzles if your settings aren’t correct, or if the chamber is too hot, so you need to leave the door open”. He gave the obligatory warning that you may need to potentially replace a hotend in a worst case scenario but being a “perishable” or “consumable” item in this hobby, it’s not the worst thing in the world if you do.
I’m confident these guys know what they’re doing. They’ve been there quite a while now. Definitely not slouches. Their bigger concern is that I don’t know what I’m doing, because I told them as much. They don’t run regular hours on Fridays, and I don’t work on Fridays so when I go in there the only one there is their modeler, who also runs the printers. Occasionally the owner is there, and there probably are more employees, just not on Fridays. I’ve just never been there during regular work hours. The modeler comes out of the back room to greet me and then lets me peruse all of their filaments and plethora of printed items on my own and tells me if I have questions to come and get him. They have multiple printed samples of all of their filaments, from very tiny things to life sized people, creatures, articulating robots and functional parts.
Being new not only to 3D printing, but to 3D modeling as well, he takes the time to answer any questions I have about either. Often times showing me how to do something in multiple CAD programs, or going through a process in Bambu Studio. I’m not sure exactly how many printers they have, but there’s a lot of them. I also appreciate the fact that he told me he’s not very familiar with the dual extruder on the H2C rather than attempt to BS me into believing he knows everything. They are quite literally 4 blocks from my house. Getting advice from someone in person who does this not as a hobby, but for a living, is a resource I think anyone new to this world would appreciate.
Unfortunately their print profiles will not import into Bambu Studio because they’re not compatible with the H2C’s dual extruder. They’re bundled with Orca, but there too, when trying to use Orca, I get an error essentially telling me it’s not compatible with the H2C’s dual extruder. My only regret is that they’re not there on Saturday or Sunday to answer questions.
Have you considered lying to the machine and calling it Generic PLA, then just adjusting the parameters to whatever it is in that profile you have in hand.
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