Hi,
I recently got a UM3E for my research lab, and it worked perfectly for the first week.
Over that week, i was playing with different material, extrusion head, and all sorts of tweaks (as I did to my UM2E), and it worked fine.
Someday, I found out that it couldn't print the initial layer successfully, and never worked since.
I'm suspecting there's something wrong with the z-axis calibration or temperature control or extruder stepper control... but, really, I have no clue what's the cause... it never happen to my UM2E before...
any idea?