R/C Airplane Wheel 70mm/2.75"

myminifactory

While I am blessed to have access to a paved runway at my R/C club, sometimes it makes more sense to use the grass for departures and arrivals. The 2.5 inch wheels I had on my plane were barely adequate, so I drew these up in Fusion360. They are 20mm wide, a dimension I copied from the handful of production wheels I have in my parts bin. The holes are sized for 5/32" axles. (4mm.) I did have to chase them with a drill bit for a better fit. If you need a smaller axle hole, for instance 1/8", I suggest shimming with brass or aluminum tubing. Print 2 rim-halves from PLA or PETG with the spokes facing upwards with no supports.(Trust me, the overhang will print nicely on a decently-tuned profile.) I suggest 15-20% infill in gyroid or cubic. There are 2 tire files; one of them features a brand-name on one sidewall which probably only amuses me. Anyway, print one tire. I used YOYI "Black Flexible TPU." I ended up using about 20% infill to get a decent looking top layer. The tire will print on its side with no supports. If you want a "Dude-bro" tire, I suggest printing with the brand name on the build plate. Once you have 2 rim halves and one tire, glue one rim to the tire with 5 small dots of Medium CA on the sloped part of the rim. Add a few dots of CA to the mating face of the rim, and glue in the other rim half, again with a few small dots of CA on the sloped part of the rim. You'll notice the whole thing snaps together and stays put even without glue, but I would not expect that to survive even a greaser landing. I have tested these wheels in service on a 4.5 lb (2 kilo) taildragger and they perform very well, giving decent traction for taxiing on paved or grass surfaces, and absorbing a decent amount of energy on touchdown for low bounce. Mine weigh about 20 grams apiece.