Step 1: You only need
- a sharp cutter knife (and a rule!)
- the template (flatcryptex.pdf)
Step 2: Prepare the base material
- Print the template
- Paste the template on the cardboard sheet
- LET DRY (over night, to be sure!)
- As you can read on the template at this step, you will have 3 layers (bottom, middle, top)
- Crop, but do not harm yourself with the knife
Step 3: Separate the pieces
Step 4: Add the middle layer guides
Let dry (one hour should be enough this time).
Step 5: Add the top guides
Let dry (you knew that, didn't you?)
Step 6: Fix the central part of the rule
OK, this is only a fast done object for my summer vacation with my grand kids. If you have time, do the same with some nice wood (or aluminum). Print, paint, or engrave. I would be interested in seeing pictures of your results.
Step 7: How to use it
Such a coding machine is designed to use a Caesar's code encryption, which is an alphabet shifting. So let's say you want to use a +6 shift. As shown on the picture, C will become I. Or, talking about my name:
"PAPYDOM" would be encrypted into "VGVQJUE"
Pro: fits in my pocket
Con: you can not read a whole word, as with a cylindrical cryptex. You must read letter by letter!