RC_Buggy

Model Overview & Print Notes

Summary RC Buggy – Custom 2-Speed Gearbox About the Project RC vehicles have always been among my favorite things to play with. Over the years, I've tried building quite a few of my own. Here I'm sharing the designs of an RC car I built back in 2020, when I was 16. I tried to give it a buggy-style design and have shared as much of the CAD work as possible, although some details are missing. If you'd like to use any part of the designs, feel free to get in touch! Gearbox and Performance One of the main features of this project is the custom-designed 2-speed gearbox , which uses an automotive central locking door actuator to change gears. The gearbox itself works reliably , and anyone interested in building their own version is welcome to use the shared designs. I've included the available CAD and STL files to help make reproduction easier. Unfortunately, I wasn't able to record a driving video. At the time, my welding equipment and manufacturing capabilities were limited, and I couldn't properly weld the drive shafts that transferred power to the wheels. Because the vehicle was also quite heavy, the shafts broke when I applied engine power, as shown in the photos I've shared. This was a problem with the drivetrain rather than the gearbox itself. Lessons Learned Looking back, I can see a few technical flaws. For example, I should have added weight-reduction holes to the gears, but I overlooked that detail. Since they were made from 8 mm steel plate, they added a lot of unnecessary weight. The wheel bearings also ended up handling loads they weren't really designed for. Still, cutting steel, welding, modifying a chainsaw engine, and figuring out the mechanical design, electronics, and manufacturing process was a lot of fun. I learned a lot along the way and had a great summer holiday in the countryside. :) 2-Speed Gearbox – Required Components For anyone interested in building the gearbox, here is the list of additional hardware required alongside the manufactured and 3D-printed parts. Bearings 9 × Bearings — 8 mm inner diameter, 16 mm outer diameter, 8 mm width (flanged versions preferred) 2 × 8 mm bore pillow block bearings 2 × Bearings — 5 mm inner diameter, 10 mm outer diameter (for the gear-shifting mechanism) Bolts, Nuts and Washers 12 × M4 × 15 mm set screws (grub screws) 16 × M8 nuts: 2 × Flange nuts 9 × Standard hex nuts 5 × Nylon-insert lock nuts 1 × M8 threaded rod 21 × M5 nuts 1 × M5 threaded rod 16 × M4 washers 2 × M3 bolts with matching nylon-insert lock nuts 1 × M4 bolt and nut (for attaching the custom-designed adapter to the actuator) Gear-Shifting Mechanism 1 × Automotive central locking door actuator (12 V) The actuator is used to move the custom-designed gear-shifting mechanism between the two gear positions. Final Notes This project was built using the tools, materials, and manufacturing resources I had available at the time. Although the complete vehicle had some limitations, the gearbox was successfully built and operated reliably. I hope these designs and photographs can be useful to other makers interested in mechanical engineering, custom transmissions, and RC vehicle development.