I first met Bob Burnside at Burning Man, Every year he sets up a table in the center camp tent and offers free instruction and materials for anyone to make his lovely geometric sculptures, a variety which are shown below.
All the sculptures are made from the same stock, a thin wooden strip with a perfect equilateral triangle cross-section. You weave the strips together in various arrangements (all based on a 12-node). As you can see there is a huge range of structures which can be made, depending on the lengths you cut the rods to, and their numbers in the array.
Kids love to try this. Burnside’s table is always crowded with the few kids who make it to Burning Man. While Burnside has a fabulous galley of possibilities on his website, there is very little instruction there. That’s because it is extremely hard to describe how to assemble on these interlocking pieces. In fact the simplest unit of 12 pieces looks easy but actually requires a teacher near by to unravel the inevitable disorientations — unless you are natural geometric genius. It would take some fiddling and puzzle solving to simply accomplish this one basic unit without any outside help. Hint: Use several rubber bands to hold the stack together as you keep adding rods.
The other challenge in this wonderful design system is that there is no commercial source of the triangular rods that I know of (Please email if you have a source.) That means you need to make the wooden strips yourself (as Burnside does), using a table saw and pine shelving. Well, all I can say is that this is easier said than done. Getting a load of perfectly triangular sticks at the 3/8 scale you want is very hard and requires some patience. You don’t have to use wood of course. I haven’t found a source of alternative triangular stock yet, but I am looking.
All in all this is a wonderful project to do with kids. It’s challenging enough to require parental assistant in the beginning and indeed will offer plenty of challenges to the GeekDad himself.