Helical Gear Cups

thingiverse

These cups boast an outer surface shaped like a helical gear. Each horizontal cross section is essentially a standard gear, with layers beneath rotated slightly to form teeth that spiral upwards like the double helix of DNA, but with 12 and 20 teeth instead. The second helical cup functions as a cage gear, meaning its teeth are freestanding and connected only at the top and bottom. It's surprisingly robust and barely deflects when squeezed firmly, despite being made up of numerous parts. Removing some of its surface would not have affected its interaction with opposing gears, leaving smoothness unaffected. The cage gear was designed to securely hold a toothbrush, allowing it to drain excess water. In contrast, the first cup – which I call "closed" – is geared towards pens on your desk. These cups utilize two standard skateboard/fidget spinner bearings: the 608ZZ Shielded 8x22x7 Bearing. Two cups not enough? Check out this modular version that can accommodate as many cups as you want! Big thanks to tbutters for their contribution!