Part of that is probably because we’ve gotten so good at making them that they’re seen as cheap commodities, but the physics and engineering behind the screw thread is interesting stuff.

The bearings actually squeeze the rod a little bit, making a temporary indentation in the surface that works just like a screw thread would. As the bearings roll on, the rod bounces back to its ...

These fasteners have been designed to assemble unconventional materials, such as ultra high-strength steel and bioplastics.