RC Speedtank with brushless directdrive

thingiverse

I was on the hunt for a budget-friendly solution to get my tank powered directly without relying on a 3D printed gear. I still had some old MT2216 T engines from the multicopter world that I wanted to repurpose for this project. The goal was to make it fast, and it did deliver. With a 4S setup, speeds of approximately 30-45kmh should be achievable, provided you've got an optimal surface. The chains are printed using TPU in vase mode. It's essential to pay attention to the extrusion factor to ensure optimal adhesion between the perimeters. If you don't, the chains will delaminate quickly. You'll want to use a medium to soft TPU since the engine's torque from a standing start isn't very high, and hard TPU is impractical in this context. I'm using Extrudr TPU with medium hardness, and it's working out great. Some parts need to be printed twice, but then they're mirror-inverted. You'll need: * 2x directionhelper for sidecovers.stl (1x normal, 1x mirrored) * 2x esc holder.stl (optional, 1x normal, 1x mirrored) * 2x wheelcover inside.stl (1x normal, 1x mirrored) * 2x wheelcover outside.stl (1x normal, 1x mirrored) In addition to the printed parts, you'll also need: * 1x RX for remote control * 10x ball bearings (external pressure gauge 16mm, inner diameter 5mm, width 5mm) * 8x M3x35mm screw for mounting the two wheel units on the main unit * 4x M3x10mm for the months of battery holder on the main unit * 4x M3x10mm for mounting the motor holder on the main unit * 8x M3x8mm for mounting the top and bottom sides on the main unit * 8x M3x8mm for mounting the motors on the motor mounts * Optional 4x M3x8mm for mounting ESC brackets on the main unit * Optional 3x M3x6mm for mounting the GoPro holder on the front cover * Some adhesive tape (double-sided) for the assembly of electrical components Nuts aren't required as everything is screwed into plastic threads. Be careful not to tighten the screws too much, as this can cause problems. If a thread starts to turn over, you can simply drip some glue in there, let it dry, and then screw the screw back in. As long as you're not planning on going anywhere, the screws will hold up well. Printing things in the orientation shown should result in no issues and won't require any support structures. The print time comes out to about 25 hours. It's recommended to print the drive wheel from PLA/PETG, while the other wheels can be printed in TPU for a slightly damping function and quieter operation. The LEDs are WS2812 and controlled by an Arduino Nano v3.