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4 V Top View
With a close look you will see that Spherical Geodesic Structures uses a different geodesic geometry to simplify the manufacturing and construction methods. The original 4V history uses 6 cord factors with the letters B and C very close to the same. On spherical geodesic structures over 50 feet in diameter this difference can begin to be a concern in more accurate
connection systems. To make construction of 4V geodesic dome kits more user friendly Spherical Geodesic Structures has combined the B and C cords and lettered them C's. We have renamed the F cords as B's.
Looking at the top down on the 4V hemisphere we can see the five major triangles that make the
Icosahedrons cap. The A struts connecting at the centers of the pentagons. Following the A-B-B-A
struts you can find the corners and (pentagon centers) of the major triangles
There are four struts that run from corner to corner of the major triangle. This is why it is called a 4 frequency geodesic structure. There are twenty major triangles to create the complete 4V
icosahedrons sphere. Five on each of the ends and ten facing each other around the middle or center.
