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How to Make a Geodesic Sphere Out of Wire

A sphere is the most efficient shape. That is, it̵7;s the shape that encloses the greatest volume compared to its surface area. But if you were to try to build a sphere you would need to build with curved materials, and the material would have to be very strong to hold against the forces trying to deform it. Buckminster Fuller faced this problem and realized he could build a shape that comes close to a sphere, but with straight struts constructed in the most structurally sound shape of all: the triangle. Geodesic spheres approximate a real sphere by putting nearly identical triangles together, with all their corners at the surface of a sphere.

Things You'll Need

Stiff wire
Wire cutters
2 pair of needle-nose pliers

Instructions

- 1
  Select a wire gauge stiff enough to support the size of structure you̵7;re building, but small enough to be workable. This will vary depending upon the material you select also. As an example, you could make an 8-inch-diameter sphere from 10-gauge solid copper wire.
- 2
  Calculate the number of segments you need for your choice of dome design. Domes are classified in terms of their ̶0;V̶1; number, which is a measure of how small the triangles are with respect to the overall size of the sphere. The number of struts will be equal to 30 x V^2 = 120 for a 2V sphere.
- 3
  Calculate the length of the segments. The easiest way is to visit the dome calculator at DesertDomes.com, but you can also find the length information in other online resources. For an 8-inch-diameter sphere, you will need 60 lengths of 2.5 inches, and 60 of 2.2 inches.
- 4
  Cut the segments to length, adding 0.5 inches to the length calculated in the previous step. Straighten the segments of wire, using the two needle-nose pliers to hold each end, if necessary.
- 5
  Bend one end of each of three longer segments into a hook, and the other end into a circle. The hook or circle will be made out of the ̶0;extra̶1; 1/4 inch on each end of the segment.
- 6
  Make a triangle out of the three prepared segments, putting the loop end of one over the hook end of another.
- 7
  Prepare six of the shorter segments, putting circles on both ends of three of them, and one hook and one circle on the ends of the other three. Create a triangle from each pair of shorter segments, joining them with one of the sides of the already-built triangle. The loops of the shorter sides will go over the existing hooks from the existing triangle, while the opposite ends will join loop-over-hook.
- 8
  Repeat the pattern you established with the previous three steps. Your finished sphere will consist of 20 units identical to the one you̵7;ve created. Each apex of one of the inner triangles will match the apex of a neighboring inner triangle, while the outer, shorter segments will share sides with a neighboring identical triangle.
- 9
  Fold the hook over to retain the loops when a junction is complete ̵2; it has all the wires attached that need to be there to build the triangles. Tighten all the hooks a final time when the last triangles have been assembled.

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