About this 3D model

Inspired by the above thing, I wanted to try a linear bearing made using airsoft balls.http://reprap.org/wiki/Printable_linear_bearingThe linear-2.2 (same has 2.1 but closed) have a bit of friction (because the balls don't make a loop) but it works (25mm long x 23,41mm ext diam)Video : http://youtu.be/GTtfGQe4o7o