Now, this is a question! Good information from Michael Kay and Quora
Wooden gears were once commonly used in industrial technology to transmit power.
So, not only is it possible to build wooden gears, it was actually done for hundreds of years. And so, by examining how those gears were made, we can build them today. Many of the problems involved in wooden gear machinery were solved by using the appropriate wood for each element of the gear. For example resilient beech would make excellent shafts. Hard maple would be a good choice for the gear teeth.
“You never really think about it, but the origin of gears is wood, essentially based upon the “Wheel”.