Recursive racks

These parts make an expanding recursive mechanism. 

The file contains four boxes and eight racks, with equal numbers of each handedness of boxes and racks. The parts are designed to be held together with M3 bolts (16mm long). By combining differently handed racks and boxes in various ways you can get lots of interesting effects.

The parts are designed to be printed with 0.2mm layer height to give the right clearances.