Detachable z-probe for Kossel fan holder by marbalon

This is my second approach to z-probe for my Kossel Mini. First I made [z-probe with "big" offset X=30 Y=-25](http://www.thingiverse.com/thing:1343493) and it did not work well for my delta.

I decided to make something with offset X=0, Y=0. So here it is... and works great
https://www.youtube.com/watch?v=979OLxXgeoE