K8200 Auto bed leveling with ballograf pen

I needed an auto bed leveling for my K8200 printer. Found some but most of them uses a 9g servo that places a micro switch on the bed. The problem with that is that the angel on the servo can't be exact the same every time.

So I made another design based on "agence_akira" high precision probe http://www.thingiverse.com/thing:490024

But some lack of materials generated a complete new desing using stuff I had at home. Designed it as a "module" for use with other printers as well. Basic brac