Dome 3 + Base Option with X1 struts

Top, front and side views:


With surface shading
All the triangles of the 3 frequency 5/8 dome are halved symetrically.
By turning the domefor Edge Zenith orientation it can be an exact 1/2 sphere: the Bucky Ball divided twice.
For a  40  ft. diameter dome one 4 x 8 sheet cut diagonally can cover one of the main triangles.
105 sheets would be required for this 40 ft. dome. With Max use of 8 ft lumber, a dome of 37 feet can be made: the longest
strut will be 8 ft. There are 270 struts. Here is the 1/5th section pattern for the paper model:

Five of these pattern sections will make the dome model.

Aluminum hub Connector Kit for 2 x 4s with a small section of a 22 ft diameter dome assembled.
Note that there are 2 sizes of hubs, larger are for the 10-strut and 12-strut hubs.
4-way connections are made with Simpson Strong Tie connectors and large screws into the X1 strut ends.