Cryptex

Last crawled date: 1 year, 10 months ago

DESCRIPTION

The cryptex is a customizable puzzle box. Give it as a gift, use it for storage, or simply put it up as decoration. You can customize the colors, passcode, and lid graphics based on your printing choices.

The code can be adjusted to any four-number combination through the rings that are printed and the order in which they are placed. There are three options for the graphics on the lid: a robot face, a rose, or plain. Since each piece can be printed individually, you’re free to get creative with color combinations.

To open the cryptex, line up the numbers of your passcode with the nub on the edge of the lid. Pull up on the lid, and your cryptex will slide open to reveal its internal compartment!

3.4" L x 3.45" W x 2.74" H
86.36 mm L x 87.51 mm W x 69.71 mm H

DESIGN PROCESS

The cryptex was created in 2017. I redesigned it in 2019 and then again in 2020.

It was first made as a gift for the graduating members of my high school robotics team (see image 8). The team wrote thank-you notes on pieces of paper and packed them into the cryptex to be given to the seniors at our end-of-the-year banquet. The robot lid design is our team mascot/logo, and the rings originally only spelled 1-3-5-1 (our team number) as the code.

I redesigned it in 2019 to be compatible with both FDM and MJF printing. In the original FDM version from 2017, the lid and the bottom had to be printed in two separate pieces. The separation of the pieces was to avoid supports, which would waste time and filament and increase the chance for error. The print time was still almost eight hours and required multiple runs to produce all the parts. In the 2019 redesign, the lid and the bottom are printed as one piece. Since SLA/SLS/MJF/PolyJet methods rely on powder/resin to support the structures, the concern over supports is gone.

In my 2020 redesign, I created the rest of the ring numbers, encompassing 0-9 for total customizability of the passcode. I added the plain and rose lid options to give people more control over the cryptex appearance. I've gifted the cryptex many times over the years. It works both as gift wrapping for small objects/notes and a gift itself as a practical storage piece.

I want the cryptex to continue on as a special gift. I hope others can customize it exactly as they wish for their loved ones.

MANUFACTURING

There are two versions available: glue (FDM) and no glue (SLA/SLS/MJF/PolyJet).

For the glue version, the top and bottom are printed as two pieces (Top_Lid + Top_Body, Bottom_Base + Bottom_Body). After printing, place the rings in the order you desire on the Bottom_Body. The rings will be sandwiched between the Bottom_Body and Bottom_Base. Align Bottom_Body and Top_Body to the indents in Bottom_Base and Top_Lid and glue the pieces together.

For the no glue version, simply print out the top and bottom as one part (Top, Bottom). After printing, squeeze the separated walls of the Bottom and fit the rings over the lip in the order you desire.

Materials Tested: PLA, ABS, Nylon, Nylon PA12
Methods Tested: FDM, MJF
Printers Used: Lulzbot Taz 6, Lulzbot Mini, HP Multi-Jet Fusion

In the photos, the purple/black model is Nylon PA12 (MJF) and the teal/black model is PLA (FDM). Hard plastics like ABS, PLA, and Nylon are best for this design. They lend durability and strength for a long-lasting piece.

Although I haven't been able to test it, I expect that the no glue version would work well with SLA, SLS, and PolyJet technologies. I'd love to be able to access any of those technologies so that I can try printing the cryptex as one unit rather than the separate Bottom, Top, and rings. Perhaps one day I'll have another redesign!

For more production instructions and details, check out the design on Thingiverse: https://www.thingiverse.com/thing:2792267

ADDITIONAL INFO:
Tiina Otala | otala001@umn.edu
University of Minnesota - Twin Cities