Building a Mach 3 Guided Rocket: A No Effort November Deep Dive
0:00 Introduction and Sponsors: The video showcases a Mach 3 guided rocket with control tabs in the fins, sponsored by Razer and NVIDIA.
0:44 No Effort November: The creator declares this video as part of "No Effort November," focusing on a technical deep dive of the rocket airframe construction.
1:06 Prototype with Birch Wood: Initial fin prototypes were created using birch wood to test tool paths and refine the CNC milling process before using expensive carbon fiber.
1:29 Leading Edge Chamfer Technique: A clever method using a fence and indexed fin placement was devised to ensure consistent leading edge chamfers on both sides of the fins.
2:10 Servo Testing (Overvolting and Runtime): MKS 6160 servos were rigorously tested, including overvolting experiments (up to 4s LiPo) and runtime assessments under load. This revealed the servo's ability to withstand high static loads but a lower than advertised torque output.
6:25 Insights from MKS Servos: A phone call with MKS Servos yielded a more detailed spec sheet and highlighted the importance of managing heat buildup in the coreless servos during operation.
7:15 Design Considerations (Fin Tabs, Nose Cone, Simulations): The video briefly touches on the importance of fin tab sizing, nose cone shape, and guidance, navigation, and control (GNC) analysis using CFD simulations.
7:33 Razer Blade 16 and NVIDIA Studio (Sponsor Segment): The creator highlights the significant performance improvement offered by the Razer Blade 16 with NVIDIA GeForce RTX 4090 for CFD simulations and video editing, emphasizing the benefits of NVIDIA Studio drivers for accelerated rendering and encoding.
9:13 Carbon Fiber Fin Cutting: The fins were cut from expensive, quasi-isotropic dragon plate carbon fiber using a CNC router. Safety precautions, including HEPA filtration, respirator, and eye protection, were emphasized due to the health risks associated with carbon fiber dust.
11:57 Servo Integration and Epoxy Potting: Servos were integrated into the fins, prioritizing stiffness over serviceability. Aluminum tape was used to protect the motor section during epoxy potting.
16:10 Carbon Fiber Conductivity Issue (and Solution): A critical error was discovered where exposed servo cable leads shorted against the conductive carbon fiber fin, causing servo failure. The issue was resolved by insulating exposed leads with CA glue.
17:46 Raceway and Cable Management: PWM extension cables were routed up the rocket's airframe within epoxy raceways to protect them from the Mach 3 airstream. Challenges with cable placement and epoxy overflow were encountered.
27:26 Structural Integrity Concerns and Stiffening: Concerns about structural integrity at high speeds led to the addition of a coupler tubing section and a carbon fiber layup to reinforce areas of the airframe.
36:23 Sanding and Surface Preparation: Extensive sanding was performed to smooth transitions and rough surfaces, highlighting the challenges of using structural epoxy for fillets and raceways.
37:08 Rail Guide Installation: 3D-printed PLA rail guides were attached, acknowledging their potential to melt off during flight but prioritizing their function during launch.
38:06 Sanding Damage to PWM Cable (and Repair): Accidental sanding damage exposed a PWM cable trace, requiring repair with epoxy.
39:10 Paint Preparation and Application: The rocket was prepped for painting with sanding, cleaning, and a base coat of white spray paint. Techniques for spray painting and the importance of a witness sheet were discussed.
40:59 Future Steps and Conclusion: The video concludes with a preview of upcoming tasks, including nose cone construction, copper tip application, avionics integration, and further simulations. The importance of learning from mistakes and sharing knowledge within the community was emphasized.