I'm printing mostly with ABS. Great for printing overhangs without support but due to the slight up-curl and the speed of printing it sometimes happen that the model is bumped off the build plate.
A way around this is to use z-lift. This do however slow down my printing time considerably. Would it be possible to ensure that the approach to a overhang area is always from a non overhang area (especially not starting over the area as the fast moving head is more likely to bump the model) or maybe even better to implement z-lift when passing over an overhang area only.