This project was really just me having fun before I graduated from my high school, where I had access to the machining equipment necessary to complete the project. Unfortunately, I did not have enough time to finish all of the parts. However, I do have enough to give a very clear idea of what it will look like. Though the gearbox was designed to be used on a FRC robot, it will probably never see use.
This tutorial was made through the Autodesk FIRST High School Intern program.
Aluminum Hex Bar
The PDF attached to this step is a complete Bill of Materials for this project. It includes information such as the quantity, cost, material type, and vendor for many of the required parts.