WLToys a9x9 Hexless Wheels and Tires

thingiverse

The tires on my trusty WLToys A979a are finally showing their age, along with the wheels being completely worn out and held together by glue. Since a replacement set would cost around $15, I thought it was worth giving printing some new ones a try. These tires are designed to be "airless," and they're locked tightly onto the rim for both side loads and rotational movement. They have a small texture that helps them grip, but they're not ideal for grassy terrain. If there's enough interest, I could post my design for grass-paddles. I spent hours experimenting with different materials, focusing on finding the right balance rather than achieving maximum grip. Since cheaper TPU's didn't work well on another car, I opted for NinjaFlex instead. This ends up costing around $2.50 per corner, with the wheels accounting for about 19 cents of that expense. So far, I've put my new tires through their paces, driving aggressively and going through around 20-25 batteries each lasting 1500mAh. While I'm starting to lose the first layer on the knobby parts, they still have plenty of life left in them, so this won't be a $1-per-run endeavor anytime soon. If there's enough interest, I might consider creating a larger rim and less NinjaFlex version later.