Ingeo PLA - Stick away
My printer works fine now, and has printed MM models reliably for a week 24/7. So I thought I'd look into my issue with Ingeo PLA filament. I have a spool of Natureworks and lots of Sakata. All printed well on the MK2s without MMU. I have used the same stuff (but 3mm) on a UM2 for more than a year without a single problem. Thickness tolerances are quite good (1.68+/-0.03).
Now that my printer is properly set, I could get a finished single color Marvin on 7 out of 10 spools, but the finish looks terrible (some underextrusion and what I can only describe as similar to extreme Z banding). 3 failed after about 50% with blockage right below the hotend PTFE - yes I tried different temps as well. No improvement going as low as 200 or as high as 215.
Apparently that filament performs really bad with the custom MMU heat break, building up friction somewhere. I can exclude retraction settings, it stays the same if I use zero retraction. I can as well exclude Bondtech tension, it never digs into the filament and the surface is smooth with no slipping until it blocks (and all my other PLAs print fine). Failures are random. For good measure I popped a spool in the oven for a few hours to make sure it is dry - no change.
All the spools are less than 3 months old and went straight from the package into a dry box. I used the same slicer settings throughout and successfully printed the same with PR PLA to make sure all my attempts didn't mess up the hotend.
My resumee can only be to stay away from Ingeo. Too bad I have so much.