Building an ESP32 Powered Warhammer 40k Rhino with Dynamic LED Effects! -- Episode 673

Clem builds a fully programmable lighting controller for scale models using an ESP32-S2 micro-controller. Designed to fit seamlessly into a Warhammer 40K Rhino tank, the controller supports up to 13 lighting channels and 3 servo outputs, with ultra-small SMD LEDs hidden inside the model. Clem shows how to plan sub-assemblies, modify and paint the model, and integrate the electronics without compromising the original form. He also walks through the custom PCB design, Arduino code, and how random lighting effects give the model a lifelike touch.

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Blood for the Blood God! LEDs for the Hobby Desk!

Clem opens with an unexpected serving of "Khorne Flakes" for breakfast. The realisation that his trusty Corn Flakes have been tainted by the demonic forces of the warp cannot be tolerated "This heresy cannot stand," he declares, pushing the cursed cereal aside. To atone for such blasphemy and restore balance to his hobby desk, Clem sets out on a mission worthy of the Emperor Himself: building an illuminated Warhammer 40k Rhino, a classic war machine of the 41st millennium.

Praise the Omnissiah! The Tech Behind the Build

To bring the Rhino to life, Clem turns to technology that would make even a Tech-Priest nod approvingly. At the core of his project is the ESP32-S2 micro-controller, a modern marvel equipped with USB-C for easy programming (because only the truly heretical would still use micro-USB). With simple-to-solder headers, Clem's setup supports up to 13 LED channels and 3 servos, enough to make his model shine like a sainted relic of the Adeptus Mechanicus.

The PCB design follows a clever strategy: the ESP32-S2 module is hand-soldered on one side, while the remaining components—resistors, capacitors, and connectors—are reflow-soldered on the other. "Double-sided assembly doesn’t have to be a warp-spawned nightmare," Clem says, showing off the clean, efficient layout.

A Rhino with a Unique Paint Job

For the paint scheme, Clem chose to move away from traditional Warhammer 40k faction colours. Instead, the Rhino reflects the element14 community, sporting a clean mix of blue and turquoise accents. An orange '14' regiment marker is prominently featured, giving the vehicle a unique and recognisable look.

The painting process itself is straightforward and focuses on achievable techniques. Washes, edge highlighting, and subtle weathering add depth to the model without requiring advanced skills. The result is a grimy and vibrant design that stands out while retaining a grim-dark feel. Key parts of the Rhino are assembled using friction-fit connections, ensuring easy disassembly for upgrades or repairs without sacrificing the integrity of the build.

Arduino Code and the Power of Faux-Multitasking

The magic of the project lies in its coding. Using vector tasks in Arduino, the LEDs are programmed to behave independently, creating realistic effects such as headlights, plasma glow, and pulsing interior lights. This approach allows for simultaneous operation without interference, mimicking true multitasking in a straightforward way.

To make the lighting even more immersive, the blinking and fading effects are based on randomly generated tasks. These tasks create variations in timing and intensity, giving the impression that the model is "deciding" its own lighting behaviour. Over time, the lights shift and change subtly, avoiding predictable patterns and creating a more "lively" appearance. This randomness enhances the illusion of a living, breathing war machine with its own personality, adding depth to the build.

The result will win no painting competitions, but could inspire some community members to add custom electronics to their next static models!