What is Happening??? Lulzbot Taz 6

Hi all - I am a high school teacher relatively new to the 3D printer-verse. Our printer occasionally messes up a job where it looks like it subtracts from the y coordinates and, after many layers starts printing several mms above where it was. Sorry if this doesn’t make sense. My kiddos are trying to print their phone case prototypes and I have attached a pic of what happens during the job. Any ideas?

Hmmm, its definitely weird and makes me wonder if its a model issue. When you load this model, after you hit prepare look at the layer view and make sure if you go through all the layers that the printer can actually print everything. You should see an outline of the Object, if there are gaps than chances are the part was designed too thin in those areas and the printer just can’t print it.3

It might not be the case here but hopefully someone else can chip in. Also try posting this in the “hardware” section, it tends to get more attention.

You have layer shifting. Depending on how the part was oriented on the bed will tell you which axis is shifting. Usually this is caused by binding and the troubled axis skipping stepper motor steps.

If there are inconsistencies, best use a newly formatted SD card, assuming that you are using one.
Also, it would be best to re-slice and use newly generated gcode, if nothing on the printer was changed.

I have also seen this caused by a broken Y axis motor wire and a failing Rambo Y axis driver.