Henry Ford's grandson wanted to have a dome built to cover the open courtyard of the Rotunda Building at Ford's River Rouge plant. Investigations showed that a conventional dome to cover the 93ft court would weigh 160 tons. Since this would crush the Rotunda Building, Henry Ford II was not especially keen. His engineers were sent to Fuller, who told them that a geodesic dome would weigh 8.5 tons.
The dome incorporated octet trusses, whose 5oz component struts were machine-made to very high tolerances (0.005 inches, instead of the traditional eighth of an inch).
The 19 680 yard-long struts were colour-coded for ease of assembly into triangles. These were connected to form larger triangular units, in turn assembled as 12ft octet truss complexes each weighing only 4lb. Such small weights meant that no great cranes or heavy machinery were needed.
The dome was designed, produced, tested and installed in 4 months: 2 days before the deadline.
Together with the transparent skin of polyester fibreglass, the dome weighed only 2.5lb for every square foot covered. (Fuller later designed a transportable dome for Ford, at twice this diameter, weighing only 5oz per square foot covered: ephemeralization.)
This design clearly illustrates Fuller's approach to weight.
© Paul Taylor 2001