The small gear makes two turnovers, while the large gear makes one turnover only.
My idea is to use a large gear as an alphabet wheel (put one letter on the each tooth) while the teeth of a small gear are marked by letters or symbols of the secret message (length is not greater than 10 letters).
Here is an example of substitution cipher edu-games.org/printables/secret-code.php
I am looking for an alternative mechanism for encrypting the message.
Question. What are the sequences of letters (symbols) I can use on both gears?