Aug 29, 2022
Throughout the Fall, I will be working on various 3D printed remote control projects. The first of these projects will be a printed-in-place car with a working drive axle and front-wheel drive. This model is the latest revision of the Gamma car found on Thingiverse. This model requires a relatively simple array of parts, including a 130-sized electronic motor (standard hobby DC motor), a 3.7-gram servo, a small 1 or 2-cell battery, a 20-30 amp speed controller, a receiver with a compatible transmitter, m2 screws, and an 8 tooth pinion gear.
To get better prepared for this project, I started to do some test prints of the car. It was stated on the Thingiverse description that not all slicer software will work with the Gamma file due to the small included supports that hold up the front top wheel while printing that you later snap for free rotation. Through my testing, I got one print to come out successfully due to the extremely sensitive nature of the design. Unfortunately, I snapped the back axle while testing the fits for the DC motor. I attempted to reprint the car but ran into quite a few issues. It seemed as though the filament was not sticking to the print bed and would leave stray lines of filament following the nozzle. To fix this, I attempted a firmware update, adjusting the nozzle’s zero-bed level, and changing the filaments which did not seem to change the outcome. After going through a multitude of first-layer calibrations for the printer, I was able to reprint the chassis shown in the attached photo. I will most likely continue to use this chassis for testing the fits of the components while attempting to make the horizontal shells come out cleaner and less jagged.
While troubleshooting the printer settings, I started to assemble the materials needed for the RC car and test out the wiring. I was able to pair the transmitter and receiver, allowing the servo and the motor to turn when manipulated on the controller. While working on the electronics, I ran through a few more test prints I was able to reach a desirable quality. With the car chassis printed, I was able to mount the DC motor and the servo arm attachments which helped to see how much room I had to work with. Though the wiring works as is, I most likely will use a smaller servo and a smaller battery so everything fits better into the shell of the car as the servo I’m currently using seems to hit the top of the car's shell when manipulated. To secure these components in the car, the original creator suggested using double-sided tape. I'm hoping that the tape can withstand the force of the servo turning the front axle as it has the capability of being manipulated extremely quickly.
While I continue to finish this print-in-place car, I will be updating these projects on my Thingiverse page, found through this link. With the experience I’ve gained by working on this car, I’m excited to move towards more challenging RC vehicles that push the limits of their technology.