Penultimate Unit: 60° angle (modified unit) for triangular faces

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The 60° unit originally presented for the Penultimate Unit requires either many layers of paper to be hidden, resulting in thick and rather unwieldy units, or that excessive paper be cut away. My solution to these problems, presented below, is a modified approach in which the triangular face is not flat. This means that polyhedra with triangular faces end up with a somewhat different look, which makes a number of new, interesting shapes possible. Each triangular face looks like a small bump which can either be directed towards the outside of the model for decorative effect, or inwards in which case the edges look like a narrow wireframe mesh. These bumps can also be connected into clusters, for example into bundles of five, placed over a pentagonal face of a polyhedron. There are lots of possibilities, and I think they nicely enhance the number of shapes that can be made with just the regular Penultimate Units. Some models for inspiration:

See other sections of this tutorial for instructions on folding and connecting other variants of this unit.

Step 1
1. Start with the 90° unit (instructions here)
Step 2
2. Valley fold at a 45° angle
Step 3
3. Valley fold so that edges align
Step 4
4. Repeat on the back
Step 5
5. Finished unit
Step 6
6. Finished unit seen from the other side