Building large wheels for a robot that are lighter weight than the rubber/ steel hub surplus stuff. Tools required are a circular saw, a jig saw, at least 3 clamps, a heat gun, a hacksaw and a drill/driver. Materials required are 3/4 inch plywood, 3/8 inch plywood, and 1/8 inch hardboard. Also required are 1 1/8 inch drywall screws and adhesive.
Laying out the wheel
Start with deciding what diameter wheel you want to build. In this build, I went with a 10 inch diameter wheel, with a 5 inch wide "tire". In this step it is crucial to have as close to a perfect right angle to start with as possible. It's a major part of your layout to have it.
I used a scrap of 3/4 inch plywood that I had laying in the shed for the wheel itself. I also used 3/8 inch ply to make the braces to support the tire. I will go into those more on the next step.