Octogon - Fast bed calibration

thingiverse

This surface is nice and enough to manually adjust the bed and level it's central area, doing it fast. My bed is not a completly regular surface and there is no point on trying to level the whole thing. Most of the things that I print do not have a very wide base, so they rest in a small area at the center of the bed. That central part is the one I find useful to be perfectly leveled.