Step-by-step build log: hobbyist RC tank with metal tracks, stabilised turret, IR battle and realistic sound.

Step-by-step build log: hobbyist RC tank with metal tracks, stabilised turret, IR battle and realistic sound.

Project brief and goals are simple to state but demanding to achieve, namely a durable hull with metal tracks, a stabilised turret that keeps the gun on target, a reliable IR battle system for skirmishes and an audio setup that makes the model sound convincing on the field. I set an initial budget and parts list, chose a 1/16 scale platform for balance between weight and detail, and sketched a wiring diagram before buying anything. The log that follows is the order I found most practical, and I documented the parts, CAD files and notes on my site at https://watdafeck.uk for anyone who wants to replicate the build.

Chassis and metal tracks were the logical starting point because their weight and geometry determine motor choice and suspension layout. I used laser-cut steel for the roadwheels and sourced a set of pre-assembled metal tracks from a hobby supplier, but many builders will weld or 3D-print track links and plate them for realism. Key steps were machining the sprockets to match the track pitch, fitting sealed bearings in the return rollers and designing tensioners with screw adjusters so the tracks do not derail. As the metal adds mass, I upsized the gearbox and used dual brushed motors with adequate gearing to keep crawl speeds realistic while allowing for speedy manoeuvres during play.

Turret stabilisation is the feature that transforms a toy into a convincing scale machine and it was the most technically involved stage of the build. I fitted a two-axis gimbal using coreless brushless gimbals salvaged from camera stabilisers and mounted a 6-axis IMU module on the turret ring for motion sensing. Filtering the IMU with a complementary filter and then a small Kalman stage reduced jitter, and the control loop runs on an STM32 flight controller configured as a rate-stabilised servo driver. Power was routed through a compact slip ring to maintain continuous rotation without tangled cables, and PID tuning was performed on the bench using a soft target before field tests to prevent hunting under recoil simulation loads.

For the IR battle system I used a purpose-made tank combat board with selectable pulse modulation and safety cutouts, and I added a secondary microcontroller to manage hit logic and respawn timers. The emitter diodes were mounted behind a scale gun muzzle with a beam shaper to match expected spread, and receivers were positioned around the hull and turret to register hits from different angles. I implemented team codes, a friendly-fire filter and a visible hit LED along with a simulated smoke output for "critical" hits, and thoroughly tested the range and interference resilience at different angles and lighting conditions to ensure consistent performance in skirmishes.

Realistic sounds really sell the illusion on the battlefield and I spent time mapping audio events to vehicle states using a 16-bit audio board with an on-board amplifier. Tracks have a separate looped rattle, engine idle and acceleration are crossfaded according to throttle input, turret traverse has damped mechanical whine and there are discrete cues for firing, hits and immobilisation. I mounted a water-resistant speaker under the belly to keep audio plausible and routed a small transducer to the turret for gun reports, synchronising recoil with short motor kicks for tactile feedback. Final polish included environmental samples for mud and gravel that trigger according to wheel slip sensors and a command to switch to "quiet" mode for indoor play.

Final assembly was a long process of iteration involving weight distribution tweaks, EMI mitigation to keep the stabiliser and IR receivers happy, and field tuning the control gains during mock battles. The tank now holds up well under repeated play, the metal tracks give it authentic weight and sounds, the stabilised turret keeps first shots on target and the IR system makes team games strategic and fun. Follow me on: Facebook: https://www.facebook.com/watdafeck3d · Instagram: https://www.instagram.com/watdafeck3d/.