Indeed I never go beyond 60C without glue or anything, just a very clean glass and OFC calibration calibration calibration.reibuehl wrote:For PLA this is really strange - especially with such small objects like the robot. I always use 60°C for PLA - often without glue, sometimes with glue - but don't see such warping. But I also haven't used Ultimaker PLA in a long time. Have you checked the bed to nozzle distance recently? I had bad bed adhesion in the past when I didn't level the bed after a nozzle change.
UM2 Automagic calibration assumes 0.1 gap while doing it. So to force it to squish to the bed use a 0.05-0.08 gauge feller.