Website: thingiverse
Author: AdditiveTech
Price: Free Download
File format: .Stl 3d printable
Description:
https://www.youtube.com/watch?v=oY7d8ZlgCuwThese cups have an outer surface that is a helical gear. Each horizontal cross section (like the top surface) is normal gear. Each layer beneath is rotated slightly such that makes the teeth form a helix. Think DNA double helix, except with 12 and 20 teeth.The second helical cup