Being sort of a geek, and having a bent for math, I am fascinated by Malcolm Tibbetts "Perpetuity", "Neighbors" and similar pieces. I did some web surfing, and discovered there is a whole branch of mathematics called "knot theory", which was part of my inspiration.
For my Trefoil pieces, I started with a Sketchup model, scaled it down to reasonable size, and took measurements off of the model to prepare my cutting list.
There are some interesting features that made it easier to design and assemble these pieces. First, in the plane of each pair of legs, they meet at exactly 45 degrees. One leg is slightly longer than the adjacent leg, so it can all fit together. So I only had to make three identical pairs of legs.
For this one, I used only straight tubes of rings. They were assembled from staved tubes, cut into short rings, and brick layed around a dowel armature (Jerry Bennett technique).
Comments and critiques welcome.
