About this 3D model

Somewhat parametric, kinematic mirror/lens mount for steering optics. http://en.wikipedia.org/wiki/Mirror_mount It contains a living hinge in one corner and two magnets in the adjacent corners. These magnets are attracted to a pair of set screws used to adjust the mirror angle. The size of the magnets match those in the makerbot platform. There are both imperial and metric mounting versions. Imperial uses a 1/4" hole, while metric uses a 6mm hole to match the optical benches. Alternatively if you need a cheap optical rail you can use T-slot extrusion like I did in the photos.