About this 3D model
I broke the lasercut parts for the Z axis endstop activator holder (see photo of wooden parts that hold the screw which triggers the endstop) while assembling my Printrbot Simple kit so I took the STL parts and merged them in Tinkercad to make a preassembled replacement. A perfect replacement although I did have to tap the holes to get them started but you could easily use a drill bit. This thing was made with Tinkercad. Edit it online https://tinkercad.com/things/gUXLF4Brtcb