RE: Core One crash/restart
I also have a factory assembled unit. Experienced the same crashes with my unit as described above. After chatting a while with support, I found this thread and applied the fix. No more crashes since then.
Thanks @darkmattermaker for finding this fix!
RE: Core One crash/restart
Hello,
I received the conversion kit last week and I'm in the middle of setting it up. Finding this topic here is real luck. Thank you very much! I can now make sure that both of my motors are well earthed during assembly. In hindsight, I'm also glad that the delivery took so long. This tip and the numerous other recommendations from the comments in the assembly instructions save a lot of time and trouble. No one ever has the same chances if they are one of the first to be supplied.
However, I think it's a pity that the proposed change has not (yet) become standard for Prusa Support. It would be quite easy to measure during printing with an electric field meter (field mill) whether and how static electricity builds up and suddenly discharges with the described effect of the reset. Then it would be a fact and no longer an educated guess.
Someone could also make a note of this change in the comments to the assembly instructions. Then it would be documented in another place in addition to this thread.
RE: Core One crash/restart
Someone could also make a note of this change in the comments to the assembly instructions. Then it would be documented in another place in addition to this thread.
Done. See: https://help.prusa3d.com/guide/5-corexy-assembly_872604#879336 - I believe comments need to be approved so this might not show up immediately.
RE: Core One crash/restart
@bowtie6 and all others with pre-assembled printers.
Note that the build of the printer includes a ground wire to a "faston" connector on the X-Y motor plate so adding additional wires for the motors should not be necessary. What is necessary, due to the manner in which the X and Y steppers are mounted, is to remove at least one mounting screw (from below the X-Y frame) for each motor and either clean away the powdercoating where the screw head contacts the frame or add a "star" type washer (thanks @ckobar) that will penetrate the powdercoat to create a path to ground through motor mounting screw. The issue identified by @darkmattermaker is due to there being a fully insulated (except by chance) mounting of the stepper motors to the frame (they sit on PCCF plastic mounts screwed to a powder coated frame).
Hopefully this saves some people time and energy correcting the problem as it requires less disassembly and modification to the printer.
RE: Core One crash/restart
[...] remove at least one mounting screw (from below the X-Y frame) for each motor and either clean away the powdercoating where the screw head contacts the frame or add a "star" type washer (thanks @ckobar) that will penetrate the powdercoat to create a path to ground through motor mounting screw. [...]
Hopefully this saves some people time and energy correcting the problem as it requires less disassembly and modification to the printer.
Can't be said often enough. 😎
But I'm afraid unless you post a few colorful pictures too, people will overlook this suggestion, just like the several earlier posts recommending it.
RE: Core One crash/restart
@jurgen-7,
You are probably correct but as I haven't yet performed this mod on my own printer (no issues yet knock-on-wood 🙂 ) I don't have any to share. Maybe a link to the assembly manual showing the screws in question (on one motor) will help: Securing the Y-axis motor. Remove the powdercoat (or add a star washer) under the head of at least one screw indicated by the "pink arrows".
Regards,
Steve
RE: Core One crash/restart
Same problem, did many prints successfully until I tried one diagonal print that causes the printer to crash and reboot 6 times during the print. As suggested here, I grounded the X motor housing to the chassis and so far, no more crashes.
RE: Core One crash/restart
Thanks guys! I have started building my conversion kit Core One and have already bought some star/teethed washers! Will install one underneath each X and Y motor.
RE: Core One crash/restart
Per-assembled version, just recently started having this crashing issue during a large petg print, with long diagonal X Y movements. I came across this thread and tested the grounding of the X Y stepper motor housings and found X to not be grounded. Like Ckobar suggested, putting an internal tooth star lock washer under one mounting bolt fixed the issue. Both motor housings are reading as grounded and print has completed successfully 2 times now.
I installed one on the Y as well just to cover my bases.
RE: Core One crash/restart
Usually (and in my case) the Y motor was already grounded. Check first with a multimeter or a continuity tester. I only had to ground the X motor on mine.
RE: Core One crash/restart
Hello!
Today I finished assembling my MK4S->CO upgrade kit. My first printing attempt was a support to anchor the MMU3 unit on top of the CO, and it's a long diagonal piece. My first printing attempt failed miserably. I spoke with Prusa and they told me directly that they would send me a pair of XY motors. I read this post and it's exactly my problem. I ran to grab my tester and tested the ground continuity and saw that the left motor wasn't making contact with ground. I made my own ground cable and grounded the motor, and I'm now printing successfully, so luckily it worked for me too. Many thanks to the creator of this post and to all of you in general!!
RE: Core One crash/restart
After finishing the assembly of my Core one, I started getting the same problem on my long prints. I read through the blog reply's on grounding the X motor, so I removed the screw next to the heat bed and used a Dremel to remove the paint from the frame around the screw hole. I installed the screw back and so far the problem has stopped. I tried this shortcut since I didn't want to take the printer a part again.
RE: Core One crash/restart
So my core one just started doing this today. Originally on firmware 6.3.2 but after updating to 6.3.4 it is still happening. After loading filament and selecting to confirm I have loaded filament… it reboots itself. First time was after an overnight filament ran out change. Second time was after flashing the Prusa and trying to print for the first time I had to load filament.
Prior to today I have done a number a mid print filament changes to change color without issue.
RE: Core One crash/restart
Hi all,
Has this issue been solved? My core one was working great for a few weeks untill today I encountered the exact same issue.
Lights out, everything stops, a few beeps and then it starts up again.....
RE: Core One crash/restart
Hi all,
Has this issue been solved? My core one was working great for a few weeks untill today I encountered the exact same issue.
Lights out, everything stops, a few beeps and then it starts up again.....
If you're having the static buildup issue, you can remove one of the screws holding each of the "X" and "Y" motors and install a star washer under the screw. Or remove one screw and scrape the paint around the hole.
No, there's no fix other than that.
RE: Core One crash/restart
Hi Thanks for responding, it was indeed the static charge.
Removed 1 screw on X and Y motor, scraped some paint off around the hole with a drill bit and it's fixed. Did not have to disassemble anything, screws were reachable from the front, with the X rail moved all the way to the front.
Thanks!
RE: Core One crash/restart
I also agree that the Core One has a grounding problem. Like others on this thread I've had an issue with the random restart. It would happen every few minutes on basically every print. I pulled out the multi-meter and checked the ground for the x-axis and y-axis motor. The x-axis motor had a lot of resistance in the ground path, but it was somewhat grounded. the y-axis motor was not grounded at all. So out comes the handy-dandy Dremel tool with a small grinding attachment and I exposed bare metal underneath one mounting screw on each of the motors. Reassembled and checked again. Both motors now had good ground with no resistance. Printed a part that I was having huge problems with and no further issues.
What is silly is that it is such a simple fix. All Prusa has to do is include some star washers to be used when mounting the x and y motors. Why didn't I use them? Well it was 4 am and my local hardware store was closed and I wanted to see if this was the problem.
RE: Core One crash/restart
Just received my assembled Core One and after a few successful smaller prints, I put it on a longer print (PRUSA toolbox) and it failed 4-5 times before I found this thread... I did notice the Z-axis is also not connected to ground... is that an issue or since it is so slow, static isn't an issue?
RE: Core One crash/restart
I'll have to let others answer. I never checked the z-axis as grounding the x-axis and y-axis fixed my issues completely. What's weird is that support seems to have no idea what the true fix is to these issues. My support person contacted me and I explained this thread and the solution and how it fixed every issue I had. He basically wrote back and said "huh, that isn't in our list of fixes".
RE: Core One crash/restart
My sense is that the Z-axis grounding should not be an issue here, the leadscrews in the trapezoidal nuts should not be capable of building much (any) static charge. The working theory is that the movement of the belts across the pulleys builds static charge which, if significant enough, discharges into the frame suddenly and causes the electronics to react poorly. By grounding the X-axis and Y-axis motors to the frame with the star washer or removing powder coat the static charge can continuously bleed off to ground and there won't be a significant discharge event. The reason that this only manifests on large prints is likely because the much longer high-speed movements cause large "spikes" in the static buildup. During smaller moves the energy levels aren't so high and the static will naturally dissipate to remain at "safe" levels.
Regards,
Steve