RE: Nozzle cleaning consistently fails with PETG
I have had similar issues with PETG and the Textured PEI build plate. I spent quite a bit of time with Support Chat and narrowed down part of the failure to the Silk Screening on the build plate itself. I swapped to the build plate from my MK4S which the silk screening has worn off quite a bit and have been having far fewer issues. I even ordered a 3rd party textured build plate from Amazon with no silk screening and have nearly eliminated the issue. I do from time to time have a small amount of ooze coming out that gums up the startup but I usually check it before printing or wipe it with a brass brush before walking away from it. I've been told that it is a known issue and that a firmware update in the future will most likely fix it.
RE: Nozzle cleaning consistently fails with PETG
The firmware update seems to have fixed the issue. I have started 2 PETG print jobs after the firmware update and haven‘t had any nozzle cleaning error.
RE: Nozzle cleaning consistently fails with PETG
I actually had a nozzle clean failure (after 6.3.1) on some Prusament PLA (it was that gray hexagon shaped april fools spool, probably at max "Wetness" for PLA if that's a thing). So it just kept making blob after blob on the bed and never "cleaned" fully. I'm wondering if changing filament right before a print could still have the issue because the filament would not be retracted as from a previous print, if that's makes sense.
Maybe it could retract at the beginning of prints before each cleaning instead then load before purge? I've been up since 3 AM, probably missing some obvious reason not to do that 🙂
RE: Nozzle cleaning consistently fails with PETG
I actually had a nozzle clean failure (after 6.3.1) on some Prusament PLA (it was that gray hexagon shaped april fools spool, probably at max "Wetness" for PLA if that's a thing). So it just kept making blob after blob on the bed and never "cleaned" fully. I'm wondering if changing filament right before a print could still have the issue because the filament would not be retracted as from a previous print, if that's makes sense.
Maybe it could retract at the beginning of prints before each cleaning instead then load before purge? I've been up since 3 AM, probably missing some obvious reason not to do that 🙂
If it's oozing just heat up the nozzle up to temp and let it sit for 5 minutes. It'll stop. Hit the nozzle with brass brush and start the print. Works every time.
RE: Nozzle cleaning consistently fails with PETG
Sorry to hear that.
After my Firmware update the printer asked me to run a Z-Axis calibration. Maybe that was the key to success together with the new Firmware.
Apart from the printer head stopping at the right rear edge when the job is finished, I always head a quite significant amount of filament hanging at the nozzle. I always removed it by pulling it down. Without any further cleaning the next prints have always been successful so far - with PETG. I don‘t remember any PETG job, which started like that without nozzle cleaning error before the firmware update. So the update (probably together with the new Z-calibration) made the printer as perfect as I expected. I am really happy now.
I haven‘t tried PLA (which always worked) after the update - I hope the Problem has not been moved from PETG to PLA.
RE: Nozzle cleaning consistently fails with PETG
After the firmware update to 6.31, the nozzle cleaning issues stopped occurring for me. Previously, it happened almost every other print, but now it hasn't happened for about 20 prints. Let's hope that was it.
RE: Nozzle cleaning consistently fails with PETG
Nope, still there. At least for higher temp materials. Issue is, according to one github issue that the hotend interfers with the HX711. Unloading helps as the hotend is less active, but the issue is by no means resolved. If that really was the issue, the only solution I see is to stop heating the hotend at least for a short time it takes the measurements off the HX711. If this doesn't help it will result in a change of hardware.
RE:
Happy to report that I had an easy nozzle clean with Prusament PC-CF. Did a long purge ahead to be sure nozzle was clean and extruding well. Two or three bumps and started the print. ObX .04 nozzle, temp 285C, Prusa Slicer standard. Filament dried and printing out of dry box. Just one attempt, but seems good now.
RE: Nozzle cleaning consistently fails with PETG
I was only referring to PETG. However, I've since done a few test prints with CPE and ASA, and I had no problems with nozzle cleaning there either.
RE: Nozzle cleaning consistently fails with PETG
Prior to the firmware update, I always had nozzle fails with PC-CF. So, the firmware update seems to have solved that, I imagine the issue affects more than just PETG. In changing from PC-CF back to PLA I had a nozzle clean fail. Perhaps residual PC-CF, a long purge fixed that. Still early days but the firmware update seems successful.
I was only referring to PETG. However, I've since done a few test prints with CPE and ASA, and I had no problems with nozzle cleaning there either.
RE: Nozzle cleaning consistently fails with PETG
Regarding the "nozzle cleaning failed issue" I am now able to use my CORE One with the same reliability than my MK4S i.e. just click "print" and get my part when finished. The only thing to do is to grab the oozed bit of filament from the nozzle while removing the part and the intro line, and it's ready for the next print. On this aspect the CORE One firmware do a good job with the new filament retraction procedure, hope they will merge this improvement to the XL and MK4S.
I don't know if it's my fiddling around the Nextruder cables, the firmware update or both but the things are getting better. Excepted for VFAs unfortunately. 😪
RE: Nozzle cleaning consistently fails with PETG
Sharing my experience so more data is available for other people looking up this issue. Nozzle cleaning step fails consistently with PC-CF, and TPU. I've read this entire thread, so I am up to speed. I have not messed with any of the load cell wiring as previously mentioned by others. I was hoping this latest firmware update would do the trick, but it has not.
- -Core one pre-assembled
- Firmware: 6.3.1+10362
- -Obxidian .4mm HF nozzle
-MK3.5, MK4+MMU3, Core One
RE: Nozzle cleaning consistently fails with PETG
Btw this also happens at every print with Prusament ASA too, i then have to go to the printer and repeat it.
Why can i not do this trough connect ?
Cmon Prusa ...... I am disappointed
As you have to attend the printer to load fresh, dry filament for each print you may as well start it then and there rather than starting it remotely later after waiting while it absorbs moisture so that you get a second grade print. It's usually the moisture that causes the oozing... Connect makes some sense for a print farm with attendant employees but very little for an individual user.
Cheerio,
RE: Nozzle cleaning consistently fails with PETG ***SOLUTION***
My issue is constant nozzle cleaning failures coupled with sporadic crash detection warnings during the initial nozzle cleaning process. After a crash-and-retry, the bed often seems to lose its z-axis settings, and has no idea where it is. You can see it rising and falling slightly in the center of its range—as if it's coordinating with the nozzle when in fact the nozzle is nowhere near the bed. I try pre-homing before I print but the issue persists regardless.
I've tried...
- Soft resets; hard resets.
- Upgrading firmware to the latest (currently 6.3.1).
- Different nozzles, different filaments, different print sheets. I have more success with the Prusa stock nozzle than the Diamondback one, but the problem exists with both.
- Nozzle thumb screws engaging but not tight; nozzle thumb screws hand tight.
- Fan screws loose, hand tight, somewhat tighter with tool.
- Loadcell screws loose, moderate, tight.
- Nozzle all the way in as far as it can go; nozzle all the way in minus about 1mm.
- Belt tension matched at 82Hz, 85Hz, 88Hz.
In all cases, the nozzle is clean. In all cases, there is no dripping filament. In all cases, nozzle-tapping leaves no filament dots on the print sheet.
And I can't stress this enough: in all cases, prints come out perfectly—once I get past the initial nozzle cleaning issue (by trying over and over—sometimes for hours). If there was something truly out-of-whack with the printer, then I wouldn't be getting great prints.
While the Prusa folks have been genuinely helpful trying to find a solution, the only solution I have found that works is to disable the specific part of the process that is failing...
In PrusaSlicer —> Printers —> Custom G-code —> Start G-code
Comment out (or remove) the following...
; ; MBL ; M84 E ; turn off E motor G29 P1 ; invalidate mbl & probe print area G29 P1 X150 Y0 W100 H20 C ; probe near purge place G29 P3.2 ; interpolate mbl probes G29 P3.13 ; extrapolate mbl outside probe area G29 A ; activate mbl
Add this in its place...
G29 ; Full mesh bed leveling
RE: Nozzle cleaning consistently fails with PETG
Regarding the g-code I posted, I'm not certain that...
G29 ; Full mesh bed leveling
...is enough to actually activate the bed leveling. So maybe use...
G29 ; Full mesh bed leveling M420 S1 ; Turn mesh leveling on
RE: Nozzle cleaning consistently fails with PETG
This is clearly a bug in the software/process during the cleaning stage. I just had a print fail multiple times (this is not the first time that this happens). I cancelled the print, TOUCH NOTHING ELSE, and the print then started after the very same cleaning process, which had now passed - mysteriously -. This is clearly a software issue, and needs to be addressed asap, along with the door sensor issue that trips the machine.
The list of bugs in the software is too long for me to tolerate, but I am giving Prusa 2 more weeks in case the release a software update for these things.
I really want to keep this printer as I have already invested too much money in spare parts, sheets and other things that I have started using... plus a huge bill from fedex due to importation taxes. I am not sure what the process to return it is and I am not sure that I can get that tax money back.
At this price point and I want to click print and forget. If I wanted to watch paint dry I would get an Ender 3. I am paying for top notch tech, I should get top notch tech.
RE: Nozzle cleaning consistently fails with PETG
There are quite a few on the forum now with the Core One. I'd be interested to see if everyone is having issues.
RE: Nozzle cleaning consistently fails with PETG
My machine is unusable and it is going back to Prusa next week. I am 99% now looking to get a full refund and walk away and never look back.
RE: Nozzle cleaning consistently fails with PETG
There are quite a few on the forum now with the Core One. I'd be interested to see if everyone is having issues.
I had issues, but the software update seems to have resolved them. I notice the filament is retracting now after I loaded it and purged.
Before the software update I did disassemble part of the nozzle once because I had filament firmly stuck. That gave me a chance to tighten all the screws, so maybe a combo of software update and me faffing with it worked?