After the frame I started making the wheels which I decided to cut out of 4mm plywood on a laser cutter which I had access to at school. The wheels are made of 3 layers of ply, the outside has a diameter of 200mm and the inside has a diameter of 198mm. I stuck the wheels together using PVA glue and clamped them together amd left them for a few hours each. This small gap in-between makes it so I can fit a rubber O ring around the wheel for better grip.