Introduction: 300 Million Custom Combination Cipher Lock

The 300 Million Custom Combination Cipher Lock can keep all your valuables safe. The design features 6 selection rings with 26 selections per ring; that 26^6 combinations or 308 915 776 combinations!!! That will keep the thieves busy.

Using set pins, users can choose and re-choose what they want there combination to be. The 26 faces on each rotary ring is intended for each letter in the English alphabet however, may be re-purposed for users needs.

In order to complete this project, you'll need the following:

- 3D Printer

- Label Maker

- Hot Air Gun

That's it!

Step 1: 3D Print All Components

Set all your parts in the shown configuration to minimize support material. Any 3D printing software you choose. In experience, all the prints should take anywhere from 30 - 40 hours to print depending on your printer volume and speed. Once the parts are printed, sand all faces and edges for optimal performance.

Step 2: Assemble Components

To do this part you may choose to use a heat gun. Heat the ring components over the outer diameter of the casing. Repeat this step for all 6 rings.

Step 3: Label Lock Faces

Using a label maker, make 26 X 6 labels for each of the faces on the cipher. This project is intended for the 26 letters of the English alphabet but can be configured for other languages.


Greek symbols also look really cool!

Step 4: Set Pass Code With Holding Pins

When the Cipher is in the open position 5 mm dowels can be set in the desired position for each password combination. To change the password; simply unlock the cipher, remove and reset the pins to achieve one of 300 million combinations.

Step 5: Done!

Enjoy! Lock all your valuables away and keep them away from burgles. For optimal results, domed glass can be used to display valuables rather that 3D printed components. Be sure to comment on and share this project. Thanks for reading.

Safe and Secure Challenge

Participated in the
Safe and Secure Challenge