Material and Infill

Material

PLA & TPU

For the PLA parts I like to to use 15-25% infill with a wall thickness of 2-3. I recommend using a newly opened filament roll or one that's been properly dried as any warping could cause issues. Keep in mind not all PLA filament is created equal with some being extremely brittle("Ask me how I know").

The TPU parts consist of tires, tracks, and belts. I like to use 10% infill with a wall thickness of 2. I recommend 95A for the belts and tracks as it provides a good amount of flexibility though wont stretch so much as to cause slipping. For the tires you can honestly print in whatever you like just as long as it fits over the edge of the hub. I challenge you to find the grippiest TPU you can though haha.