Z callibration Mini Kossel

I like to callibrate my kossel without autocalibration
the problem was a better way to control the z endstops

You need a electronic endstop
Optical Endstop Switch for CNC 3D Printer RepRap Makerbot Prusa Mendel RAMPS 1.4
http://www.ebay.nl/itm/400545910883?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

1bolt 3x35mm
1 nut 3mm with nylon