TETRAHEDRA + WEIRD TETRAHEDRA

Hi. I'm stumped.  This is a post to follow the earlier CUBE + OCTAHEDRA post, both comprised of a unit designed by the talented Francesco Mancini. I don't know what one of the intersecting polyhedron in this modular ball is called (hence the post title). The compound is (I think) two tetrahedra - 4 sides, 4 verticies, and 6 edges (totally math!) - but one of them has some weird bendy-stuff going on. So I'll just leave it and say it's weird. Voila!

Again, like the 24-unit model, this 12-unit model has interesting patterns depending on which angle you view it from. The bigger version had a combination of square- and triangle-based as well as high- and low-tipped pyramids. This one is all triangle-based, and here's a diagram of the result. Bam!

NINJA SMOKE BOMBS

If I were a ninja, obviously I would carry around smoke bombs. Mine would be awesome. Because they would look like this. Beautiful geometry and such. Of course they'd be smaller for portability's sake, but you get the idea.

A Tomoko Fuse classic, from Unit Origami.

HALF SIZE

I liked my last modular project so much, I decided to do it once more but with 7.5x7.5cm paper - half the size of the first attempt. The smaller scale proved to be much more of a challenge (as one would expect) and it had me using random objects I could find to help me assemble the units together. I ended up using my painting knife to hold open some of the pieces so I could weave other pieces in. It was quite a mess.

In the end, no matter how patient and gentle I was with the paper, I couldn't get two of the flaps into their rightful pockets so they're just kind of hangin' out I guess. Other than that, it's not a bad model. The colours were a little unfortunate but it's all I had in that size. But it's a cute size, so I'm happy.

Design by Jeannine Mosley (Diagram here).

PARALLELOGRAM + TRIANGLE = RHOMBUS

Yes! I found a new puzzle today. As usual, it was a tough one that required a lot of head-scratching, jamming paper tabs into the wrong pockets, and some mild cursing. This was a very interesting piece: 12 15x15 cm square sheets, which formed 4 rings, made of 3 units each. These four rings had to intersect properly to form a stellated rhombic dodecahedron. Fun numbers.

The rings that were formed have 3 parallelogram faces and six triangular faces. When joined together, the pyramids they form has a rhombic base rather than a square base which I think is kind of cool...

The outcome was more satisfying than a normal modular ball, as generally this shape would require at least 24 units. Because it's formed with intersecting rings, it doesn't need nearly as many - it's just a bit more confusing to assemble. In the end I'm glad I stumbled across this design by Jeannine Mosley (Diagram here).