Manufacturing & Construction
The manufacturing of parts via 3D print was a lot of trial and error, but ultimately led to high quality parts. Issues included printer calibration, support material failure, and design flaws. Some parts took much longer to complete than others, but tasks were started much sooner than they were scheduled for providing time to redesign that was much needed.
Servo/Battery Covers
These are updated versions of the original covers. The Servo cover was modified to allow the steering components enough room for mounting, and the mounting holes were expanded to add strength. The battery cover was expanded to allow room for the wires to run out the back, And the mounting holes were expanded for added strength.
Prototype Mockup
Part manufacturing has begun for all drivetrain and steering parts and at least one prototype for each part has been made. Several obstacles were met when manufacturing/constructing parts, specifically with 3D printed parts. Several tolerance issues were discovered from poorly calibrated 3D printer settings that would cause the part to not finish or warp. Even with parts printing correctly, fitment was not always right especially when trying to connect two 3D printed parts together.
Transmission
CSJ-10-001
The Transmission (CSJ-10-001) shown on the left has presented the most difficulties. Several printing attempts were made before the sides could even be properly connected. This was because of warping when the parts were placed in hot water to dissolve the filler material. Once the two sides were printed correctly and could be merged, internal issues involving the gear locations was analyzed. The gears that transfer power from the motor to the differential did not properly fit. A new design to resolve the issue is underway and will provide room for gears to properly function.
Steering Servo Test
The steering servo and radio control module were taken off an old scrap RC car, so to make sure everything still worked the were plugged into a battery and tested before construction onto the RC Baja.
Transmission Graveyard
Multiple Attempts at printing the transmission were made before a working prototype was created. Pictured below is a pile of PLA material that were failed attempts.
Motor/Diff Housing 3D Print
Utilizing the Creality 3D printer in the Hogue building. White PLA was chosen for the application due to its strength. The raft of material underneath the part shown in the video helps the PLA adhere, but it can also create a warped edge one the side that is on the raft.
Drive Train Test Run
Tackling this project required breaking it into several phases. The most important stage was outlining my goals and defining the research questions. Once these were in place, I spent hours at the school library, surfed the net for online resources and carried out various experiments and tests. Writing came next, and the outcome is here for you to judge. Would love to hear your thoughts and comments - contact me at school or by email!