OpenRC F1 Gear with grub screw

thingiverse

Here are two Spur gears with added grub screws which I fitted to them. Just insert an M3 nut after the print and screw in an 8mm M3 screw. I was having trouble with the original Spur gear slipping. My first thought was to glue it in place but after breaking the rear axle three times, I was fed up with reprinting and re-gluing the gear so I made this quick and easy mod which allows the spur gear to just slide on and off and fix in place with common M3 hardware. I then moved on to the Herringbone gear I found here https://www.thingiverse.com/thing:1726861 and did the same mod. The regular gear is more durable in my experience however, I've found that the Herringbone gear makes the car substantially quieter if that's something you're looking for.