Dual Color Stellated Octahedron
2010
Single-sheet stellated polyhedra are pretty advanced but the color change brings it to a whole 'nuther level of complexity. The first challenge was to work out how to achieve the arrangement of alternating colors. I needed two corners to come to the center like a blintz but offset. Working out the amount of offset for the grid to be the right size was the key problem. It turns out the angle is 67.5 degrees, which is 3/4 of 90 degrees and easily derived. It also has a slope of 3/2, which is also easily derived from a square grid. From this I was able to work out the arrangement of the squares in the inner rotated grid and the outer triangular grid areas, which correspond to the blintzed flaps. The 3/2 slope made was convenient because the grid is has an integer relation of the unit the whole. Each square of the grid has a length of 2/13 the edge of the paper, as you can see in the crease pattern.