In this instructable I will show how to create a 3d printed cryptex. A cryptex is a device used to lock up an item and can only be opened by a passcode. Cryptexes were popularized by the movie and novel The Da Vinci Code. Some of the steps will not have a picture, but they are very simple. I designed this model on Auto Desk Inventor, and printed it with a MakerBot that my school owns. I hope that you enjoy! If you do enjoy this, please don't forget to hit the vote button and vote for me in the 3d printing contest!

Step 1: Designing the Inner Layer

The inner layer consists of a hollow cyllinder, an end cap, and multiple square pegs protruding form the top. These pegs are the key to the whole system, and for each letter you'd like in your passcode, you will need a peg. So for a 5 digit passcode, you will need 5 pegs. The dimensions I used are included, and that will produce a cryptex large enough to hold a key, a flash drive, money, and most small knick-nacks. You will need one of these inner shells.

Step 2: Designing the Outer Shell.

The outer shell consists of an end cap and a hollow tube with a slot running down the length of it. The disks for the cryptex will rest on this shell, which is slightly wider than the inner shell so it can fit cleanly on outside of the inner shell. There will also be a barrier glued to the end of the outer shell to keep the cryptex disks from sliding off. You will need one of these outer shells.

Step 3: Designing the Cryptex Disks.

The disks are what the passcode is placed on. They have a circular interior sized to just fit over the outer shell, and a polygonal outside to be able to distinguish the numbers more clearly. They also require a notch inside of them, in order to fit the peg inside. This will allow the peg to rotate as well as pass through on the specific number. This is essential for the cryptex to function properly. The disks will be placed over the outer and inner shells and held on with the barrier. The type of polygon on the outside of the disks distinguishes what type of passcode you will have. A 10 sided polygon for the outside will give a numerical pass code, while a 26 sided polygon for the outside will give an alphabetical passcode. You will need multiple of these disks, one for each letter/number you'd like to be included in the final passcode.

Step 4: Designing the Barrier

After the first prototype, I learned that a barrier in order to keep the disks in place would be needed in order for the cryptex to function properly. The barrier should have the same inner diameter as the outer shell, and the same outer diameter as the end cap. It also requires the same notch as the cryptex disks. You will need one of these. Once you have all this designed, you are ready to print it!

Step 5: Assembly

Unfortunately I do not have any photos of the process. Once you have printed out all the parts, you will want to label the disks. I did them in numerical order, because I liked the way it made them look. For the ones you wish to be the answer for you pass code label them on the side the notch is in. Then put the disks in the order you wish for them to be on the outer shell. Once the disks are around the outer shell use super glue to glue the barrier to the end of the outer shell. Make sure the notches match up. Let the glue dry.

Step 6: Congratulations!

Congratulations, you now have a fully functioning 3d printed cryptex! Now I did not include an extremely detailed process of every single little step in the designing process, but that is because I wish to encourage creativity as opposed to copying. I provided dimensions on mine as an example, but I will not provide the completed file. I welcome you to use the dimensions in your own creation! I hope I have inspired some with this instructable. Thank you!