The story behind this thing is that I had this pair of hexagonal shaped gluing jigs that I was using to help me align Pennyhedron puzzles pieces. I was using these jigs so often that they had found themselves a sort of place of honor sitting on the back corner of my table saw workbench. I got in the habit of stacking a set of 6 octahedral blocks inside of these jigs just because I thought it looked cool, and it gave the jigs a visual sense of purpose to be containing a rhombic dodecahedron.

One day when I was busy working at the table saw making cuts on some other project, I looked over and noticed that the 6 octahedral blocks had been slowly vibrating themselves out of position while the saw was running, and so that anal retentive part of me got in the habit of flushing them back up every so often over the course of many long workdays. One day as I was flushing up the faces of the blocks, I stopped to ponder how it was that each block was able to vibrate out of position in the first place, and yet still the whole structure remained relatively intact and stable.

I could tell that there was something special happening there, so I stopped the saw and spent some further time analyzing how the combination of the surfaces of the gluing jigs plus the surfaces of the 6 blocks themselves worked together to keep the motion of each block constrained. Further brainstorming ensued, leading up to the Barcode Burr interlock prototype.