What could be causing this issue? (motor stops)

I built a Corexy machine. It's running a SKR 1.3 with TMC2208 in UART and marlin 2.0 bugfix.I've had multiple successful prints. But I've also had this issue with where either the X or Y motor just stops randomly. I've also had this happen where both the XY motors stop at the same time. There are no errors on the screen and the extruder keeps going. There also seems to be a layer shift prior to this happening. This has happened with about 40% of my prints, both PLA and PETG. The speeds were set very low at 80ms for PLA and 40ms for PETG. I'm printing from SD cards. This has happened with multiple SD cards that I have formatted multiple times.Any ideas or questions would be greatly appreciated, thanks.

There are several reasons that can cause this.

1. The linear bearings could have debris causing them to miss steps.
2. The Smooth rods are lubricated with a grease instead of a light machine oil
3. The smooth rods and bearing are binding due to not being correctly aligned.
4. The stepper motor Driver module TMC2208 needs the V-Ref adjusted.

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Originally Posted by Roberts_Clif

There are several reasons that can cause this.1. The linear bearings could have debris causing them to miss steps.2. The Smooth rods are lubricated with a grease instead of a light machine oil3. The smooth rods and bearing are binding due to not being correctly aligned.4. The stepper motor Driver module TMC2208 needs the V-Ref adjusted.

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The main issue is the X or Y motor stopping randomly during the print and not starting up again. Or both stopping at the same time before the print is finished. In the first picture 1 motor stops, while the other kept going and the printer kept extruding, so you have this huge blob line. In the last picture both X and Y motors stopped at the same time mid print, and yet the printer kept extruding as if the print was continuing normally.I only brought up the miss step because it only seems to happen on prints where later down the road one of both of the XY motors will stop for the rest of the print, while the printer keeps going as if no error has happened.
It was brought up that the stepper drivers could be overheating. But I have heatsyncs on all of them with a fan blowing directly across them, and they are barely warm to the touch during a print. So I don't think that is the issue.

Did this CoreXY machine come with the firmware installed or did you choose and compile the firmware yourself.
If you choose and compiled the firmware what did you choose?

Quote:

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Originally Posted by Roberts_Clif

Did this CoreXY machine come with the firmware installed or did you choose and compile the firmware yourself.
If you choose and compiled the firmware what did you choose?

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It could totally be a problem with the firmware, I compiled it myself. Its a hypercube evolution that was a complete DIY build. The failure occurs about 40% of the time on prints longer than 5 hours. For shorter prints, they finish just fine. So assumed it wouldn't be a firmware issue. But I'm really not sure what in the firmware could cause that.

This could be a thermal issue, try cooling the controller and Stepper motor Drivers.
Also if you happen to be near the 3D Printer after a few hours carefully touch the Stepper motors to see if they are overheating.

Quote:

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Originally Posted by Roberts_Clif

This could be a thermal issue, try cooling the controller and Stepper motor Drivers.
Also if you happen to be near the 3D Printer after a few hours carefully touch the Stepper motors to see if they are overheating.

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everything is barely warm to the touch. I have heatsyncs on all the drivers with a fan blowing directly across them. Motors are not warm either during prints.

You are correct this is going to be a tough one.

I ended up fixing this problem by replacing the board. I also added a MOSFET for the bed. So it appears that the issue was a defective board. What was wrong with the board? I couldn't tell you. But replacing the entire board solved weeks of headaches.

Happy to see that your replacement Controller solved your problem.