Fabtotum leveling tool

This is a custom head for the Fabtotum 3D printer. It is used as a basic but effective comparator (micrometer) for bed leveling. The contact tip is at the same place as the nozzle, to ensure proper calibration of the bed. (The probe that comes on the Fabtotum X carriage is not aligned with the nozzle and cannot compensate for misalignment of X shafts.)
This tool can easily achieve sub-0.1mm precision.
1) print and assemble the head and arrows, using two M3 screws and nuts (or glue them all).
2) mount it on the Fabtotum, and move the carriage to one corner
3) adjust Z to just touch the tip
4) adjust the bed screw to have both arrows aligned
5) proceed to the other corners
Done.