OCTAHEDRON - Drawing a Pattern
11 minute video on drawing an octahedron pattern.
The above video describes the process of drawing an octahedron pattern. It does not show assembly. Octahedrons are composed of eight equilateral triangles. There is no need to draw any perpendicular lines. The compass is set only one time.
Critical in this demonstration is how the pattern is visualized because of the number of identical triangles, and understanding the edge connections. As patterns get more visually complex, placing tabs correctly becomes more challenging.
As seen in the video, choosing what angle to draw a 3D representation of an octahedron takes practice.
The tools used are:
- straight edge
- pencil
- eraser
- compass
Many Ways to Arrange an Octahedron Pattern
One way to study the unfolding pattern of an octahedron is to think of it as two mated pyramids with no bottom squares. In this way, you can visualize two groupings of the triangles that allow them to close up first, and then attach to one-another along the three remaining loose edges. Five layouts illustrate this concept easily, and five don't, but all of the above patterns will assemble into an octahedron.
Notice that two of the layouts have mirror symmetry, and two have rotational symmetry.
