Why did the shift occur?  

RE: Why did the shift occur?

What Filament are you using in the slicer. I was having similar issues and made sure that everything was the way everyone else recommended (avoid crossing perimeters being off, etc.). What I found was switching from using the Overture PETG profile to the Prusament PETG profile, the issue went away. 

RE: Why did the shift occur?

Almost impossible to say... not enough information. Were you present for the entire print? Did you notice extra plastic at the purge line? Wondering if the printer did a reset and missed it when redoing calibration.

RE: Why did the shift occur?

I was there. It was the first PLA print from Prus. I heard some strange noise at the time. Maybe a jam or something like that. I'll keep an eye on it.

RE: Why did the shift occur?

Stab in the dark: Did you turn "avoid crossing perimeters" on (in PrusaSlicer's Print Settings > Layers and Perimeters > Quality settings)? There is apparently a known software bug which causes the slicer to occasionally generate rapid direction changes at high speed in this mode. These cause largely reproducible layer shifts.

If that's not it, as @tim-24 said: We would need more information. First thing you should try is whether the error is reproducible or was a one-off occurrence. If you can repeat it, it would be good if you can share at least your slicer settings, or your project file (.3mf file).

RE: Why did the shift occur?

I have everything set to factory settings. I'm just getting to know 3D printing. I'll try printing again and let you know. I'd be happy to change the settings if you can advise me.

RE: Why did the shift occur?

Very unlikely a setting issue, but hey, it's a 3d printer: strange things happen.  Generally, the extruder bumps into something (more often an open frame printer); but the Core One also has a couple of quirks where is resets itself in the middle of a print. Static builds up on the belts - tho usually on larger prints. But when this happens the printer restarts and continues. I think I read there is a known issue where the restart position is sometimes off causing a layer shift.  A clue is extra filament on top the first purge, or straight strands laying around on the bed.  

Other things are to know: where did you get the gcode file for the print? Did you slice the part or get a finished gcode off Printables? Filament in the printer (Galaxy Black) PLA or PETG or ?? Is that a single part (three cats at once) or three print attempts?

RE: Why did the shift occur?

Hello. The test images are from the Prusa database free. I use Prusa start galaxy black filament. PLA. I also printed the keychaing Prusa original and it came out great. I have another question. Does the USB Prusa have to be plugged into the printer? Thank

RE: Why did the shift occur?

Also just discovered there is an issue on Core Ones printing large circles if Slicer has Avoid Crossing Perimeters checked ... probably not what's happening here, but the shift is at a circle.

RE: Why did the shift occur?

Posted by: @ttsimik

Hello. The test images are from the Prusa database free. I use Prusa start galaxy black filament. PLA. I also printed the keychaing Prusa original and it came out great. I have another question. Does the USB Prusa have to be plugged into the printer? Thank

Yes. The printer won’t operate without an USB stick plugged in. It doesn’t have to be the Prusa one specifically but not all brands work and only USB2 seems to be acceptable and only if formatted with Fat32

RE:

I just tested two different USB3 devices, one 3.0, one 3.2, they work fine.
FAT32 is a requirement.
With Windows formatting any device over 32GB as FAT32 is painful, so best to purchase 32GB devices for use with the CoreOne; that said, you can take any device greater than 32GB and erase the volume, create a new volume as 32GB FAT32 and the Core One reads it (though ignoring any second partitions).