Monday, January 30, 2012

Rhombic Triacontahedron Fabrication

A rhombic triacontahedron is a 30 sided polyhedron.


Each face is identical. It's made by taking a golden rectangle and connecting the midpoints of each edge which results in a diamond shape:


Here's the one I made from 1/2" thick walnut and ash. It's about the size of a volleyball.
 


It’s actually held together with magnets – 120 of them – one in each edge.


It was cut on a 5-axis CNC at the Taubman College at the University of Michigan. Here’s the machine and the fixture which holds the work as it’s cut.

Vacuum pressure comes through the table and fixture to hold it in place. Two tiny pins prevent it from twisting during the cutting and drilling.