MBME

Good morning, I'm having trouble leveling my Ultimaker 3 print bed. I currently have two different print cores, AA 0.4mm and AA 0.8mm, and as seen in the attached photo they are sitting at different lengths. For this reason the auto-leveling does not work. Additionally I'm not sure the best way to manually level, as sometimes only the shorter nozzle is down to touch the calibration card, and other times they both are, in which case the longer nozzle makes contact first. Maybe something is wrong with one of the cores or their installation and they are not supposed to be at different heights. Just wondering if anyone out there was also running different size nozzles like this and how you went about bed leveling. Thanks!