RE: Nozzle cleaning consistently fails with PETG
It's got to be more than just a firmware issue. I've never had an issue with any irritation, MK4 or S and I practically print only PETG. So what's making some have issues and some not?
I don't have a CO yet, but using the same extruder as the MK4 I can't see it being any different.
RE: Nozzle cleaning consistently fails with PETG
I don't have a CO yet, but using the same extruder as the MK4 I can't see it being any different.
Which actually argues for it being a firmware issue as the CO firmware is different from every other printers.
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: Nozzle cleaning consistently fails with PETG
What nozzle are you using? Seems like most reports about this problem were with HF nozzles.
RE: Nozzle cleaning consistently fails with PETG
I found the same issue before coming here to see if others were having problems. I noted that the nozzle cleaning function occurs over the prusa logo. You can feel the height variation there with your finger. Moving the sheet down a little so that it cleans in a consistently flat portion of the satin sheet fixed my problem.
RE: Nozzle cleaning consistently fails with PETG
PETG prints turn out flawlessly as soon as I get over the cleaning step! I just avoid PETG for the moment since babysitting is so annoying, that’s all.
No PETG printing at all? That sounds pretty extreme, or maybe your issue is worse than mine. For me, barring the "autowipe" mod, I could just babysit the print start with a brush for the nozzle cleaning, and after that everything is ok. I didn't know people were completely unable to get PETG prints to complete.
Thanks for the heads up on the new firmware- I've been waiting for it, especially since the MK4 got a couple of point releases in the meantime.
I have made several approaches to find the root cause. I came to the conclusion that a algorithm evaluating the load cell sensor is not correct. Talked to support several times and provided them with videos and photos. Prusa is aware of the issue and they made some tests. Last information: a new firmware is targeted for next week that also takes care of the nozzle cleaning malfunction. My advice: don’t spend more time to get it to run - I spent many many hours and didn’t get any further. I’m sure the firmware will fix it! I have 2 day’s printing time on my CO -> with PLA it prints fantastically with no failures at all. So I will not print PETG until it’s absolutely necessary. And yes, my filament is dry/new. That is NOT the cause for this particular step failing.
Cheers and happy printing, the Core One is a superb machine!
Mathias
I have perfectly dry PETG, the humidity sensor in my filment dry box says 10% humidity. My print head is super clean. Watching the process is looks more like that the petg is not hot enough and doesn't adherse to the print bed when it tires to clean the nozzle.
This is not a problem with wet filmament!
If you don't have a CORE one yet, stop telling people they should dry their filament. It doesn't help to solve the problem, thanks!
RE: Nozzle cleaning consistently fails with PETG
First I used the 0,4mm brass HF that came with the printer, now the hardened HF nozzle, both no difference, didn’t try a regular nozzle.
What nozzle are you using? Seems like most reports about this problem were with HF nozzles.
RE: Nozzle cleaning consistently fails with PETG
I found the same issue before coming here to see if others were having problems. I noted that the nozzle cleaning function occurs over the prusa logo. You can feel the height variation there with your finger. Moving the sheet down a little so that it cleans in a consistently flat portion of the satin sheet fixed my problem.
I have Core1 sheets and they don't have a logo at the cleaning positon. The logo is in the middle of the sheet.
RE: Nozzle cleaning consistently fails with PETG
I noticed that too, then used a textured sheet with no print on it (from Amazon) but didn’t make any difference, still failed the cleaning step with PETG.
I found the same issue before coming here to see if others were having problems. I noted that the nozzle cleaning function occurs over the prusa logo. You can feel the height variation there with your finger. Moving the sheet down a little so that it cleans in a consistently flat portion of the satin sheet fixed my problem.
I have Core1 sheets and they don't have a logo at the cleaning positon. The logo is in the middle of the sheet.
RE: Nozzle cleaning consistently fails with PETG
I had the same Problem on the CoreOne, but when using the 'Tune' Option and adjusting the Temperature of the nozzle to 180°C instead of the 170°C I have a 100% success rate with PETG on a textured sheet. I hope Prusa adds the possibility to adjust the temperature for nozzle cleaning in the filament profile of Prusaslicer.
RE: Nozzle cleaning consistently fails with PETG
I have been using the Core One for a few days and have successfully printed multiple times with PLA, PETG, and ASA, each with at least two different filament brands. I had no issues with PETG.
Here are some tests with PETG for the hypotheses from this discussion. The tested sheets are, from the top: Core One Satin, MK Satin, and MK Textured. On the left, prints were made using the Core One default 0.4mm brass CHT nozzle, and on the right, with a 0.6mm ObXidian High Flow nozzle.
I didn't do anything special - just started the print, took a photo when it was finished, swapped the sheet (and once the nozzle), and started the print again.
The sheets were cleaned with 99% IPA. PETG spool used in these tests was dried a few days ago. I printed with it for a few hours in a room with around 40% humidity, then stored it in a vacuum bag with a silica gel pouch. It's not perfect, but it should still be fairly dry.
It's a few years old, cheap Hobby King PETG, but that shouldn't matter. After drying, it prints like new. I've also printed with Prusament PETG and Aurapol PETG without any issues.
If you're having issues with PETG, try drying it first. And if the printed text on the MK sheets causes problems, you might try roughening it with sandpaper. (I didn't do anything to mine. There's just some wear from use.)
RE:
The obvious problem here is that it's something that doesn't affect everyone. I am sure most users are fine. However, there's a long thread on Github that indicates that there's a smaller but not insignificant group of people experiencing issues with the first layer quality. Why that is, no idea. Could be early models or late models, some difference in components, etc etc, god knows. All I can say that all my 3 Mk4S are showing the issue while, go figure, my XL-5T with very similar (but not identical) extruders has never shown it. All are running standard 0.4mm Obxidian nozzles but from the Github thread it doesn't seem like the nozzle is a decisive factor.
And I'm sorry, I know how to clean sheets, nozzles, and dry my filament. It's not as easy as that. It might be a problem for some people but I suspect not the driver for most who reported the issue on Github. I would also not consider a tiny square to be a meaningful test case, but again, I don't doubt that the majority never runs into that issue, so whatever. I for one suspect it's a combination of some mechanical variance that only exposes itself in certain configurations and the way firmware calculates the proper live Z offset (once Live Z is adjusted manually when the print starts, the first layer is indeed flawless).
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: Nozzle cleaning consistently fails with PETG
My fix/workaround: Glue spray on the nozzle cleaning area (Satin sheet).
RE: Nozzle cleaning consistently fails with PETG
Spankin new pre-assembled Core One here with same issue. Out of the box it printed several test items in PLA perfectly.
Loaded in some PETG and just immediately began to struggle... Struggled so hard I ended up here.
Tried all the things. The printer is new, not me and it's as clean and dry as it will ever be (she agrees ;P).
Was also doing the temp tune thing others tried and did get it to work once or twice maybe. Can't be sure really, def not consistent though.
Anyways, after some trial it seems I can consistently start PETG prints (YAY!!) but only by pausing the job while it's "nozzle cleaning" and then it will resume past the cleaning step and go to probing instead. FINALLY!
It still tries several times to "clean" after I press pause, and then it parks. When I resume it moves like it's going to start cleaning again, but then it just bumps the bed and continues on to probing the rest of the bed. After probing, it will then do its nozzle wipe line across that same front corner and immediately get to work on the print job. WOOT!
Once past the bogus nozzle cleaning phase, all of my PETG prints are coming out phenomenally. Or, one might say, as expected from a brand-new factory-calibrated machine sold specifically for this material? 9 complete prints so far, including several muli-hour jobs, with and without supports, etc. and not a string out of place. Literally no other issue besides the nozzle clean-nanigans.
Is there a combination shrug and chef's kiss emoji?
Hope this helps anyone else until they patch the code for it. GL
RE: Nozzle cleaning consistently fails with PETG
It happens to me too and it's very frustrating for a brand new and expensive printer! The nozzle is completely clean yet it fails. What I noticed though is that it only fails with textured sheet, so I'm stuck with printing PETG onto a smooth sheet which I hate to do with PETG.
RE: Nozzle cleaning consistently fails with PETG
I've tried 2 PETG prints and got the nozzle cleaning error both times. I retried to no avail. Then just cancelled, did a purge on the filament - cleaned it off with the brush and retried the print and both times that process worked...
RE: Nozzle cleaning consistently fails with PETG
To have a new printer, that has nozzle cleaning functions to then have to clean with a wire brush, is a bit off. It's a semi autonomous machine, to have to manually clean the nozzle, when a cleaning function is available, is a work around nobody should have to resort to at this price point IMO.
Scott
RE: Nozzle cleaning consistently fails with PETG
You're missing the point. My nozzle was perfectly clean when it failed. It's not that you have to clean it with a wire brush, the problem is that something is wrong with how it works now, and it should be repaired with the next Firmware update. I repeat, it only happens with a textured plate.
RE: Nozzle cleaning consistently fails with PETG
Have you raised the issue as a possible bug over on the GitHub site for the firmware? If not I suggest you do so: https://github.com/prusa3d/Prusa-Firmware-Budd y" href="https://github.com/prusa3d/Prusa-Firmware-Buddy" rel="noreferrer"> https://github.com/prusa3d/Prusa-Firmware-Buddy
The Prusa developers very rarely come on this forum.
RE: Nozzle cleaning consistently fails with PETG
There's one already
https://github.com/prusa3d/Prusa-Firmware-Buddy/issues/4523
Formerly known on this forum as @fuchsr -- until all hell broke loose with the forum software...
RE: Nozzle cleaning consistently fails with PETG
You're missing the point. My nozzle was perfectly clean when it failed. It's not that you have to clean it with a wire brush, the problem is that something is wrong with how it works now, and it should be repaired with the next Firmware update. I repeat, it only happens with a textured plate.
Apologies, my post was aimed at the members who expressed that cleaning the nozzle with a brush was perfectly acceptable.