RE: Core One crash/restart
Same issue here for the first time after owned the printer kit for 4 months.
I printed several small pieces theses days without issue, then I printed the 3 small boxes (see attachement) i designed for a boardgame, and it crashed 3 or 4 times always around the same spot (see picture red points).
I tested the motors X and Y with a multimeter and the X make beep the multimeter with a 0,45 ohm. The Y motor is showing nothing.
So I guess I will have to remove the paint under one screw of X motor and put a ring.
But why now...after several big prints taking nearly the whole bed (more than 72h of print time in statistics menu), it's always a mystery.
RE: Core One crash/restart
..I tested the motors X and Y with a multimeter and the X make beep the multimeter with a 0,45 ohm. The Y motor is showing nothing.
So I guess I will have to remove the paint under one screw of X motor and put a ring.
I think you mean you want to modify a screw on the Y motor. "Nothing" probably means over-range or high resistance. Connecting to ground with low resistance is (presumably) good because any static electricity can dissipate.
RE: Core One crash/restart
You're right , Y motor! Thanks
RE: Core One crash/restart
Hello,
I have a question about grounding.
Do you think it would be safe to connect a wire from this screw to the cable shown in the circle on the photo, in order to improve the ground?
Or is it a bad idea and could cause damage?
Thanks a lot for your advice!
RE: Core One crash/restart
There is absolutely no need to do anything other than ground via the motor mount screw(s). This is by far the easiest and neatest method of grounding. Check before doing anything to see that there is a resistance, then check after to make sure there is not. You cannot ground any better than 0 ohms!
RE: Core One crash/restart
After a week of messing around and chatting with Prusa (yes, you're using the Alpha version, so that must be the problem. Not). I reinstalled everything several times and adjusted the belt tension (which helped a bit), saw this post and thought I'd check it out. After properly grounding the two stepper motors, everything worked like a charm. Whoever found this and posted it here, my thanks! Hats off! 👍 👍 👍 ☕ 🍻
Prusa Core One
RE: Core One crash/restart
Hi,
I scratched the paint and checked with a multimeter, everything looked fine. But guess what – when I thought it was fixed, it actually wasn’t.
The printer still crashes. So I wasn’t as lucky as you, and I’ll have to send it back.
Very disappointed with the user experience, I have to say.
RE: Core One crash/restart
After a week of messing around and chatting with Prusa (yes, you're using the Alpha version, so that must be the problem. Not). I reinstalled everything several times and adjusted the belt tension (which helped a bit), saw this post and thought I'd check it out. After properly grounding the two stepper motors, everything worked like a charm. Whoever found this and posted it here, my thanks! Hats off! 👍 👍 👍 ☕ 🍻
That's unbelievable. After so many weeks, either the support team is unaware of the solution to the problem here—which I honestly can't imagine—or the support team is not allowed to pass on the solution to customers because the development department has not yet approved it.
In any case, it is shameful and very unfortunate that customers still encounter this error and only have a chance of avoiding it if they a) follow the English online assembly instructions and b) read the comments.
Everyone else wastes time and materials with misprints, is pressured by support to replace the motor or electronics, and in the end still has exactly the same problem.
It would be quite easy to prove whether it is actually static electricity.
Static electricity is measured without contact using an electrostatic field meter, which detects the electric field strength on surfaces and displays the value in kilovolts (kV) and the polarity (positive/negative) on a screen. These portable or stationary devices provide accurate real-time measurements and are used in industry for quality control and process optimization.
RE: Core One crash/restart
I totally share your point. It’s incredible – the after-sales support feels extremely slow and reactive, and it often seems like we, the customers, have to figure everything out by ourselves, as if there’s a kind of denial of reality.
Everyone keeps talking about static electricity, but let’s not forget that the Body3D camera also doesn’t work at all – it only connects through a phone hotspot and never with a normal router. That part alone has been a nightmare.
At this stage, I’m going to request a refund, because this product just feels like too many problems right from the start. Maybe one day a “Core Two” could be worth it, but for now I’m done.
RE: Core One crash/restart
Was in the middle of a print and the Core One just started crashing every couple minutes. Contacted support and the guy wanted to critique material temperature settings and using MMU for single color prints. Irrelevant! If the printer turns out then the temperature seemed adequate. It also seems very stupid to have to manually load filament through the MMU when printing single color when I can just paint in the slicer. it prints without issue. When questioned about how those things would cause the printer to crash he had no answer. I wasn’t touching the printer so static discharge seems unlikely. It seems gcode related. It hasn’t done it on any other file before or since. Prusa Claims to have GREAT support but twice now they have been useless.
RE: Core One crash/restart
I wasn’t touching the printer so static discharge seems unlikely. It seems gcode related. It hasn’t done it on any other file before or since. Prusa Claims to have GREAT support but twice now they have been useless.
The consensus is that the static builds up in the belts then discharges through the door sensor switch which crashes the printer. If your X and Y motor housings are grounded then it should go away.
RE: Core One crash/restart
Support asked me to check xLcd cable. I know it has been responsible for issues.
I'll see next large print if it crashes again after grounded Y motor.
RE: Core One crash/restart
Support asked me to check xLcd cable. I know it has been responsible for issues.
I'll see next large print if it crashes again after grounded Y motor.
Make sure both X and Y are grounded.
RE: Core One crash/restart
Was in the middle of a print and the Core One just started crashing every couple minutes. Contacted support and the guy wanted to critique material temperature settings and using MMU for single color prints. Irrelevant! If the printer turns out then the temperature seemed adequate. It also seems very stupid to have to manually load filament through the MMU when printing single color when I can just paint in the slicer. it prints without issue. When questioned about how those things would cause the printer to crash he had no answer. I wasn’t touching the printer so static discharge seems unlikely. It seems gcode related. It hasn’t done it on any other file before or since. Prusa Claims to have GREAT support but twice now they have been useless.
There are issues related to certain Slicer settings: one that has been problematic is Avoid Crossing Perimeters. If this is checked, the printer may make abrupt moves that cause layer shifts. Another issue has to do with Arc Fit being set on or off. Seems that can also cause abrupt head moves. These don't appear to be what you are dealing with.
The ESD is most likely belt related, static builds up during long diagonal moves, and the goal with grounding the motor cases is to provide a short path for the charge building up on the belts through the motor bearings to the chassis back to the Earth at the power supply. You can check your printer by measuring for continuity between the top of the X and Y motor cases (any unpainted area, or sometimes the motor shaft), to the spade lug in the back left corner underneath the extruder frame. If this resistance is higher than a few ohms, you are probably subject to this anomaly.
I never had the issue until I printed the sample Rocket Engine ... and it failed every time within the first centimeter. Added the lock washers to X and Y, and the next print finished without incident.
RE: Core One crash/restart
This actually makes a bit of sense. I was printing a print sheet holder. It was almost completely diagonal across the print bed and it would crash evertime the extruder traveled from the right rear to the front left. I’m not completely familiar with the lock washer fix. Is there a post that explains this better or can you elaborate? I’ll install and run it again. Thanks!
RE:
This actually makes a bit of sense. I was printing a print sheet holder. It was almost completely diagonal across the print bed and it would crash evertime the extruder traveled from the right rear to the front left. I’m not completely familiar with the lock washer fix. Is there a post that explains this better or can you elaborate? I’ll install and run it again. Thanks!
Room one screw from each of the X and Y motor. Add an internal star washer and tighten screw. With a multimeter check if the resistance between motor housing and the frame (use the faston on the frame) is low (like 1-2 ohms). If high or infinity, remove the washer, screw and scrape away some of the power coating around the screw hole and repeat.
RE:
This is the front most accessible screw on the left motor of my printer, do the same for the right hand motor. This can be done without removing anything. Just be sure you scrape the paint away under the lock washer. I used a flat pilot drill and had to remove side covers for vertical access, but an Exacto knife with a chisel blade would work just as well. A few have reported success just placing the washers, without scraping off paint.
Parts required are two 3mm Internal Star washers. External stars might work, but internals are more likely to pierce the paint.
Since you have a part known to excite the problem, the fix is immediate and appears to be permanent. You'll be able to test for success instantly.
RE: Core One crash/restart
Would a reason for the static build up be the x-belt hitting the lower screws of the two fans on the case? Mine look very close to the belt, makes sense to me the problem would get worse at more movement and higher speeds?
I Hope you can follow my train of thought, maybe screws with a smaller head would be a good idear?
https://help.prusa3d.com/guide/3-back-assembly_835506#840636
https://help.prusa3d.com/guide/5-corexy-assembly_835522#865162
RE: Core One crash/restart
In my case, and like you think those screws look very close, but it has nothing to do with the crash. If in fact they did receive an arc from the belts, I'm not convinced it would reset the printer. I am guessing the arc happens at the door switch, it's the closest open connection to the control board logic. I still have trouble wrapping my head around the belts generating the tens of kV potential needed to jump even a 3mm gap... but I can't deny grounding the motor cases works every time.
RE: Core One crash/restart
Would a reason for the static build up be the x-belt hitting the lower screws of the two fans on the case?
There's a few mm separation front-to-back between those screws and the belt on my kit-built CORE One. The pages you linked don't really show it, so here's mine, looking not-quite straight down:
I would say that if your belt is rubbing (or flapping) on those screws you probably will have a problem, but perhaps not this problem.