RE:
The print of the big model finished properly without any spontaneous crashes/reboots. Looks like this solution https://forum.prusa3d.com/forum/postid/753098/ from @darkmattermaker has solved my issue. Thanks!
I have my Core One (assembled) for about 2 weeks now and I was able to properly print all of my own 3D models, first in PLA and then later in PETG. Most of my existing models were equal or smaller than 116 x 58 mm on the build plate. Today, I tried to print for the first time a bigger model (X:200 mm, Y: 120mm, and Z: 53mm) and it didn't go well. I found out that I got spontaneous reboots during the print and after rebooting the print resumed, but crashing/rebooting again after a few minutes. I tried to switch to slower profiles in Prusa Slicer, however, the problem persisted for 3 different slicer settings. Then I tried printing my smaller model again (116 x 58 x 30 mm) and that went smoothly again. I found this article on the forum and based on it, I started measuring the resistance between the case earthing (PE cable connection) and the X and Y stepper motor screws using a multimeter. I found that the resistance was very low for the Y stepper motor, however, the resistance between the X-axis stepper motor screws and the chassis was very high. I mounted a cable similar as shown in this article to make sure there is a proper connection between the housing of the stepper motor and the housing. I have now started a new print for the big model (200 x 120 x 53) and after 1 hour and 40 min of printing no issues anymore. I keep my fingers crossed that it continues like this for the remaining 4 hrs to go (I am printing with the 0.25 mm STRUCTURAL profile now. If this print succeeds, I am going to test the high speed version.
RE: Core One crash/restart
I'm curious, is there anyone here that has heard back from Prusa support with an alternative solution?
RE: Core One crash/restart
I did hear back with my support contact citing the “unofficial” solution shared here - though he said it wasn’t an “endorsed” resolution… 😉
I'm curious, is there anyone here that has heard back from Prusa support with an alternative solution?
RE: Core One crash/restart
I didn't bring up with support. I haven't retried the same print again (it was multiple of the same item that I managed to print individually cause I didn't want to waste a roll of filament again). But I've printed several things since and no issues. Previous print that was crashing, I believe it was crashing when moving between copies (rapid diagonal movement.
Glad it seems to have resolved it though...
RE: Core One crash/restart
Solved for me!
I had the same problems, failed 1-2 times during 1st layer test (tested 3 times, failures came in every run) (just added a cube in the slicer itself 250 x 220 x 0.2mm). I removed 1 screw per motor (X & Y) scratched the poweder coating away where the head of the screws touches the gantry. (I used the allen key and a cutter knife)
I did the 1st layer test again without failures, I hope this is now solved!
RE: Core One crash/restart
Hi folks,
I just ran the same issue on my Core One, with a big print (200 x 200 x 12 mm) running in vase mode, so a lot of X and y moves. I contacted support, they told me it was a known issue with the core one. They will examine my case and come back. in three weeks (!).
I given them this topic so they can learn some useful tips about this problem.
In the meantime I will:
- check the resistivity / conductivity between motor screws and grounding / chassis
- scratching the paint and adding a dented washer
- and testing again
I noticed that on the crashed prints, when I remove the print, it sticks to the plate because of static electricity.
So here I go!
Thanks for the tips!
RE: Core One crash/restart
I promised to do another test with a high speed printer setting after doing my modification ( https://forum.prusa3d.com/forum/postid/755339/). Today, I did the test the 0.25mm SPEED preset with PETG and it worked also without any problems (printing time 4 hrs and 9 min).
RE: Core One crash/restart
For anyone who has implemented the stepper motor grounding fix, has the rebooting/crashing/puppy error resurfaced at all? I believe I was experiencing the same issue, I just didn't realize what was happening. I kept noticing on some of my longer taller prints, there would be a few spots in the print where it was leaving extra oozed filament. One night I just happened to be at the printer and it randomly rebooted, so I am surmising that the printer was rebooting and the filament was oozing in the spot where it stopped. This morning I awoke to the puppy error for the first time and that led me to this forum topic. I used a Dremel to remove some of the powder coat on the X and Y stepper mounting screw holes and I now have continuity to ground. I hope this is a long term solution and I can print in peace 😊
RE: Core One crash/restart
Just to add a little more context, I checked the printing status in my Home Assistant, and it looks like the print status went "busy" 7 times before it went unavailable. I am guess those busy periods where reboots.
RE: Core One crash/restart
Mine has not crashed again after grounding the stepper housings.
RE: Core One crash/restart
Same for me, after making sure that there is good contact between the X/Y stepper motors and the metal chassis (I used a multimeter to check for low resistance), I have not seen any crashes/reboots anymore. I did quite some high speed prints of big objects in the meantime. So I assume this is a permanent fix for this issue.
RE: Core One crash/restart
Hi, I just checked. My motorscrews are not grounded, but luckily I did not have any issues yet. Why might that be ?.
RE: Core One crash/restart
It only happened with my printer when I printed big objects (in both X and Y directions). These bigger objects cause a lot of big printhead / belt motion, which can lead to static electric charging of the motors by the movement of the belts to a point where they will discharge between motor and chassis, leading to the crash/reboot. With small objects, so not covering a big part of the build plate, I didn't have this issue (less belt movement, so less static electric charging). Another reason I guess could be that the humidity of your environment is higher, which might counteract the static electric charging.
RE: Core One crash/restart
Since I grounded the stepper motor screws I have not had a reboot. I am printing the parts for the Coreboxx and have been able to go 2 full beds of 14 hrs and 18 hrs without any issues. Hopefully this is a permanent fix.
RE: Core One crash/restart
Just got my assembled core one setup this week and had my first longer print running when it suddenly started crashing/restarting with 8-10 beeps and then resuming the print. It happened consistently every few minutes and it was also my first print with longer diagonal lines so it seems likely that this issue is the same as described in this thread.
I haven't tried the grounding fix or measured if that could be the case yet since the print is still going, but I can consistently reproduce the crash - it will crash every few minutes after a couple fast and long diagonal moves. I enabled stealth mode and it stopped crashing completely. After an hour of stable printing I disabled stealth mode and it crashed within 1 minute and then every few minutes until I enabled stealth mode again - no crashes yet after another hour++ so that seems like a functional workaround for me at least until I can try the grounding fix.
I wonder if the use of PCCF for motor mounts and the very close proximity to the very static plastic panels might be exaggerating the issue a bit. I will make a ticket with support tomorrow and see what they have to say.
RE:
I put one of these under one screw per motor. Now the motors are grounded
RE: Core One crash/restart
Just got my assembled core one setup this week and had my first longer print running when it suddenly started crashing/restarting with 8-10 beeps and then resuming the print. It happened consistently every few minutes and it was also my first print with longer diagonal lines so it seems likely that this issue is the same as described in this thread.
I haven't tried the grounding fix or measured if that could be the case yet since the print is still going, but I can consistently reproduce the crash - it will crash every few minutes after a couple fast and long diagonal moves. I enabled stealth mode and it stopped crashing completely. After an hour of stable printing I disabled stealth mode and it crashed within 1 minute and then every few minutes until I enabled stealth mode again - no crashes yet after another hour++ so that seems like a functional workaround for me at least until I can try the grounding fix.
I wonder if the use of PCCF for motor mounts and the very close proximity to the very static plastic panels might be exaggerating the issue a bit. I will make a ticket with support tomorrow and see what they have to say.
What did support say?
RE: Core One crash/restart
Well...
I've had my Core one for several weeks and so far all has been going well, until I decided to print something with a lot of x/y movement, with a print time over 3 hours. Much to my surprise, my printer has been stopping mid-print for no good reason. I found this page and found it astonishing there is a potential grounding issue. I took my printer's panels apart and followed the instructions provided by @darkmattermaker.
I made my own grounding wires for both motors. The left side is simpler to work with, because there spool holder/filament sensor is not in the way. This is what my left side looks like.
My Core One is made from a MK4S upgrade kit. Did I miss something while I put the machine together, or is this just an oversight from the folks at Prusa? Does the non-upgrade Core One's have a different grounding for the motors? Or, is there something special about the non-upgrade Core One's motors?
By the sound of things, this is not an isolated issue - this is happening with some regularity.
At any rate, thank you @darkmattermaker, @noumenonsense, and others on this thread.
RE: Core One crash/restart
Well...
I've had my Core one for several weeks and so far all has been going well, until I decided to print something with a lot of x/y movement, with a print time over 3 hours. Much to my surprise, my printer has been stopping mid-print for no good reason. I found this page and found it astonishing there is a potential grounding issue. I took my printer's panels apart and followed the instructions provided by @darkmattermaker.
I made my own grounding wires for both motors. The left side is simpler to work with, because there spool holder/filament sensor is not in the way. This is what my left side looks like.
My Core One is made from a MK4S upgrade kit. Did I miss something while I put the machine together, or is this just an oversight from the folks at Prusa? Does the non-upgrade Core One's have a different grounding for the motors? Or, is there something special about the non-upgrade Core One's motors?
By the sound of things, this is not an isolated issue - this is happening with some regularity.
At any rate, thank you @darkmattermaker, @noumenonsense, and others on this thread.
I'm glad this solved your issue! My Core One is also a MK4S upgrade. I don't know that this is a conversion-specific issue. I'm pretty sure there's a few pre-assembled Core One folks that have chimed in on this thread. I think this is just a teething issue on the Core One that Prusa will sort out eventually.
RE: Core One crash/restart
My Core One is a pre-assembled version, so this issue is not conversion kit specific.