XL pauses does nothing for over 10 seconds and oozes all over the print  

RE: XL pauses does nothing for over 10 seconds and oozes all over the print

Posted by: @tobycwood

What makes it so sad for me and why I post rants about Prusa’s lack of system testing before shipping fully assembled units as well as their not bothering to consider the lessons learned about toolchanging from E3d is that the potential capabilities of this machine exceed practically any other FDM machine ever sold in any of the 3d printing markets! I’ve been unbelievably lucky with mine and it’s amazing, but I see really serious mistakes made which were all self inflicted.

Prusa will not have the luxury of time to fully refine the XL that it had with the MkIII. Bambu will no doubt be looking at snatching the toolchanger market potential away from them and that really really sux.

I agree with this. I have been lucky with my XL as well. But now approaching 1000 hours I see some issues that should the been easy fixes and some other issues that are just very random which can be frustrating. One of which which is similar to the issue above. When I first received my XL it printed everything fine. It had a small amount of stringing but everything printed well. As the software updates have been issued I have had some random issues that can't be explained except for all the updates. These updates apparently have not been tested well. 

RE:

Same issue here. 😞

Firmware5.1.2+13478 

One of the tools freezes and oozes over the piece around 20 secs and makes a big blog. This happens almost every layer on tool 5. 

The screen freezes also during this pause. The printer resumes after almost 20 seconds.

It loooks that the printer is waiting to fill a data buffer or somethig like that.

In the video: tool 2 is printing until it changes to tool 5 (00:52). Then tool 5 extrudes over the tower and then freezes over the piece.

Any tips? Is it a firmware bug?

Thanks a lot!

RE: XL pauses does nothing for over 10 seconds and oozes all over the print

The video...

RE: XL pauses does nothing for over 10 seconds and oozes all over the print

While I understand and respect the assertion that for the OP this is not a USB key issue, I'll share my experience.

I started seeing this hanging behaviour. I also had a few weirdly failed transfers from Prusa Connect to the printer. I only used the USB drive shipped with the printer. I did a full format of the drive (not a quick format). The next print had no pause, but after the print, browsing the drive via the Print menu showed only two empty folders with weird names ("R?uB!9:0.p?E" and "4p?rk?w1.?Vb"). After this, the USB key appeared unformatted to a windows PC. I got onto support chat, did some testing with another USB key (no issues), Prusa are sending a new USB key. I'm now running a lengthy stress test ( https://github.com/ncw/stressdisk) on the supposed-faulty Prusa USB key. Of course, my PC may be more forgiving of issues at the electrical and lower-level USB protocol layers, but we'll see. It would be great to find a reliable way to validate a USB key as being "XL compatible" and non-faulty.

RE: XL pauses does nothing for over 10 seconds and oozes all over the print

as an update.

I replaced my USB a few times and the machine will still pause and ooze sometimes it can sit there for over a minute doing nothing.

Now if i use the machine as a single extruder where i never change tools the machine works fine.

So the XL machine is now acting as a PLA color selector when i print something on it.

it basically has firmware issues and corrupts the USB and the wifi never works anyway.

if i want to do a color change i'm now using my MK3S+ with MMU2 because while it will have jamming problems it still has less issues then the XL.

if i want to be 100% reliable i either have to use my MK3S machine without mmu or my MK2S machines that are 8 years old and still going in 2024.

basically i'm frustrated with the waste of time and money the XL is when prusa had almost 4 years to work out the problems and not Alpha test on the public.

thank you Sergio Morales for posting the video.

RE: XL pauses does nothing for over 10 seconds and oozes all over the print

Sometimes the weird pauses can easily be that the material preset has the standby temp way too low and before changing to the tool it has to be warned up. I don’t see in your posts that you’ve monitored this. Also You need to be sure that you have the correct tools assigned for each print feature to ensure you’re not using more tools than you really need to and also be sure the standby temps are not too low. They should be IMO about 10c less than operating temp…. Regardless of what Prusa may say.

Also… I NEVER use a supplied sd card or usb stick!!!! Why? Because when they come from the printer supplier they are ALWAYS cheap and craptastic! I buy higher end, smaller memory size sticks or cards.

Solutions for drooling have already been posted. Read the posts.

RE:

all 5 tools are pla

all 5 tools use same settings for temperature

other people have same issues.

machine has firmware bugs that have yet to be fixed.

prusa recommended fixes are disable everything and see if it still does it.

i have disabled everything it still does it.

issue occurs when your going to be using more then one tool during the print job.

issue does not occur if you have a single tool and use it for the entire print.

this is why people with single tool XLs do not experience the issue.

now Drooling.... or Oozing as its been known. is yet another issue, that has nothing to do with this situation.

RE: XL pauses does nothing for over 10 seconds and oozes all over the print

Ok… what about the standby temps? You still have not mentioned them. Also… stop using the supplied thumb drive! Get a good, name brand and don’t get a large one. Smaller men size=increased reliability.

I agree with you about Prusa’s need to fix real bugs as I’ve posted how annoyed I am that rather than fixing bugs they’re spending dev time on noise cancellation.

RE: XL pauses does nothing for over 10 seconds and oozes all over the print

I'm not 100% sure, but I replaced the supplied USB drive with a Sandisk Extrem Portable SSD (512 GB) and there were no more pauses on two different 5-tool prints. Both went fine.

Surely the supplied USB drive is something to avoid, especially on 5-tool prints.

Thanks to all for your advice.

RE: XL pauses does nothing for over 10 seconds and oozes all over the print

well that was interesting as my account would not let me post on the forums.

i'm going to try out the Portable SSD and see what happens.

RE: XL pauses does nothing for over 10 seconds and oozes all over the print

I was working in my shop yesterday while a long print was running. It was making a typical rhythmic sound that was in the back of my mind when suddenly, it stopped. I walked over to the XL and it was sitting on a single spot oozing for at least a minute, then suddenly started again. I was there to pull the glob off the print and keep it from making a mess but it did a layer shift at that point and left a large artifact that went around the whole print.

I suspect this is an error in the firmware that hopefully, they're going to eventually clean up. The XL is an experimental machine in my mind. I wouldn't dream of using it in a production environment. Too unpredictable. Too buggy. Too fresh to be of anything but a lab curiosity.

RE: XL pauses does nothing for over 10 seconds and oozes all over the print

I’ve had this same issue yesterday. First time I’ve seen it. Was a 2 colour PLA print

RE: XL pauses does nothing for over 10 seconds and oozes all over the print

so here is an update on this issue:

I went out and I bought a portable sandisk SSD drive 500Gb. The XL didn't like it and refused to see any files on it.

I went and bought a Sandisk USB 3.1 thumb drive also about 500Gb and again the XL didn't like it and refused to see any files on it.

Besides the original Prusa USB thumb drive I had a USB 128GB drive that the XL seemed to like.

Once again the machine was pausing in the middle of prints and this resulted in a bunch of head collisions and failed prints.

after doing nothing with this machine for weeks i finally decided to reset the entire machine to factory default setting with a clean load of 

firmware 5.1.2 from this new USB thumb drive.

that meant starting all over and running through the entire factory setup again.

After a few hours with the machine reset and calibrations all complete i started my first test prints.

It seems to have stopped pausing in the middle of prints. but the machine was really slow on tool changes and acting like it was hanging. i was also getting stringing.

I then went further and I disabled the anti-oozing settings in slicer 2.7.2

I also made sure to turn off the standby temperatures so that all the extruders remained at full temperature all the time.

the result was the tool changing happening with less delay and it seems the stringing problem stopped. I think the anti Oozing and standby temp was causing less molten material at the tip of the nozzle and it was getting stuck the previous layer which increases the stringing and oozing rather then preventing it.

so now my machine is not pausing as often, and does not seem to be leaving blobs on my prints from hanging and so far has stopped pausing over the prints doing nothing.

its been a combination things to try out.

i still have all my collision detection disabled as it causes more problems then it is worth.   i also didn't bother with the WIFI setup as it never seemed to work correctly and a few people reported it might have added to the machine hanging at times for no reason.

so the short of it.

if you machine is still hanging like mine was with blobs, and you have done everything to play around with the USB as the cause then move to a FACTORY RESET

with fresh non-alpha firmware, go through the entire setup process again then test the machine and see if it improved.

next step after that try disabling the anti-oozing and standby temp setting in the slicer and see if that helps.

at the moment I'm actually getting something usable out of my XL for the first time.

RE:

Another little update:

I now have a few days of multi tool change prints, with minor issues.

1) The combination of doing the factory reset, and 100% fresh 5.1.2 firmware

2) turning off Ooze protection in slicer

3) turning off stand by temperature in slicer.

has finally allowed the machine to produce decent output.

it is VERY sensitive to moisture in the air and also the filament. 

I had a situation where the room the XL is in became overly humid and the print quality went way down, requiring drying of the filament and running 2 de-humidifiers. at the same time other 3d printers in the same room running at the same time with the same filament were not effected.

i did not have enough run time on my XL to see how sensitive it is to humidity changes.

i have brush nozzle cleaners on my machine and I'm using .4 nozzles. these are definite must haves.

next step will have to be an enclosure for the machine.

RE:

has finally allowed the machine to produce decent output.

 

Can you clarify what you mean by "decent" and the opposite (indecent?) prints you've experienced?

As far as quality, I've been pretty happy with what the XL produces, except for the layer shifting which typically shows up on high Z models.

I've been using the cheapest PETG I can find (CR-PETG, about $15 a kg on Amazon) and have no issues that I can see. I have excellent adhesion to the textured plate, low to no stringing, good repeatability and good tolerance. I'm still using the stock 0.6mm nozzles. 

RE:

"Can you clarify what you mean by "decent" and the opposite (indecent?) prints you've experienced?"

Yes;

the prints were not usable as they would look like they had chicken poxs along with massive stringing and layer skips.

when using the tool heads for color changing the chicken poxs, massive stringing and layer skips resulted in parts that not only looked terrible but were structurally compromised.

I had issues with layer shifts caused by the nozzle (sensor) hitting one of the chicken pox blobs left on the print from the machine sitting in one spot for over 10 seconds just oozing all over the place. this resulted in turning off crash detection, i've never had good luck with crash detection even going back to the MK3.

now the biggest improvement came from factory reset hands down. most of the problems must have come from going from 4.X.X to 5.X.X firmware.

as with the original firmware 4 i did have less problems.

i did not have some of the original issues early users reported.

but that is the gist of it.

currently the machine is putting out usable parts with little stringing when the humidity is very low. i have not seen a reoccurance of the chicken pox blobs nor the machines pausing for no reason over a print surface. i do still see the machine hanging sometimes on a tool change, there are still major issues with the firmware.

firmware Alpha 6.0.0 is a disaster and i will not be trying that firmware again until it goes for final release.

RE:

Thanks for the clarification. I have my XL in a climate controlled room, but the humidity does fluctuate. I leave the spool on the printer and use it until it's gone without ever drying it. I typically print with really cheap filament except for final prints when I use the good stuff. Frankly, I see hardly any difference between $15/kg and $50/kg PETG in regard to print quality.

Humidity has not been an issue for me. Do you live near the ocean or large body of water?

What brand of filament are you using? How old is it?

RE: XL pauses does nothing for over 10 seconds and oozes all over the print

the area for my printers has limited climate control. 

however XL is proving to be he most sensitive to moisture of any of my machines i have several and 8 years of dealing with these machines.

i have filament dryers. and vacuum containers.

filament for the XL proved to be a problem i was using bran new Esun PLA and the movement of the machine was snapping the filament inside the tubes leading to big problems. Esun still works fine in my MK3 MMU2 its the amount of movement that seemed to snap the filament, and this was bran new spools, water was not a factor.

in the XL i use hatchbox PLA and have no issues now, again working through all the issues with my machine and have taken long breaks from it. 

so new filament, bran-new sealed, hatchbox.

other bran-new filaments i tried snapped inside the tubes.

all other 3d printers i own have no issues, nor stringing.

as for PETG i use overture and hatchbox and have had just some stringing which makes sense. also PETG can take more flex and is not as brittle as PLA

so i have not had filament snapping off.

after use all PETG goes into the dryers for a day then sealed in vacuum containers with desiccant bags.

i just purchased an enclosure option for my XL and will be moving to that as i phase out my MK3 MMU2 setup to make space for the XL and free up my work bench

where i have been testing it since January.

look i understand that the last few years prusa is basically alpha testing on customers, but with advancements from other companies over the last 4 years i expected prusa to start stepping things up they had more then enough time to test the XL machines but looks like they called it good enough and shipped it way too early and with the wrong nozzles.

you said your using the .6 nozzles if you have not bought some .4 nozzles yet i would order them and install them just nozzle will make a big difference in part quality.