How to Build a Geodesic Dome Model

The first step in making your geometric dome model is to cut triangles from heavy paper or transparencies. You'll need two different types of triangles. Each triangle will have one or more edges measured as follows:

Edge A = .3486
Edge B = .4035
Edge C = .4124

The edge lengths listed above can be measured in any way you like (including inches or centimeters). What is important is to preserve their relationship. For example, if you make edge A 34.86 centimeters long, make edge B 40.35 centimeters long and edge C 41.24 centimeters long.

Make 75 triangles with two C edges and one B edge. These will be called CCB panels, because they have two C edges and one B edge.

Make 30 triangles with two A edges and one B edge.

Include a foldable flap on each edge so you can join your triangles with paper fasteners or glue. These will be called AAB panels, because they have two A edges and one B edge.

You now have 75 CCB panels and 30 AAB panels.

To learn more about the geometry of your triangles, read below.
To continue with your model, proceed to Step 2 >

_{More About The Triangles:
This dome has a radius of one: that is, to make a dome where the distance from the center to the outside is equal to one (one meter, one mile, etc.) you will use panels that are divisions of one by these amounts. So if you know you want a dome with a diameter of one, you know you need an A strut that is one divided by .3486.}

_{You can also make the triangles by their angles. Do you need to measure an AA angle that is exactly 60.708416 degrees? Not for this model: measuring to two decimal places should be enough. The full angle is provided here to show that the three vertex of the AAB panels and the three vertex of the CCB panels each add up to 180 degrees.}

_{AA = 60.708416
AB = 58.583164
CC = 60.708416
CB = 58.583164}