The cryptex consists of two main parts, the core and the mantle. The core is just a tube with some notches. For building the mantle five gears were stacked together. Each gear consists of three parts:
The inner dynamic ring, carrying the alphabet and having an inner tooth gear. A gap in the ring defines which letter lets the core pass in and out.
The ratchet ring, serving as a ratchet together with the tooth gear.
The mounting ring, holding the dynamic ring in place.
Thank you for inspiration from http://www.instructables.com/id/Laser-Cut-Cryptex/.