Notes

Notes on building Li-ion battery packs from 18650 and 21700 cells: sizing the heat-shrink tube, recommended cells, and how series vs. parallel wiring affects voltage and capacity. Heat-Shrink Tube Sizing For a 4S1P pack using 21700 cells, the shrink tube should be 90 mm wide (21 mm × 4 cells = 84 mm + a small margin). Tools You Need To solder 18650 or 21700 cells you ideally need: A spot welder (around €50 on Amazon) Balance leads Positive and negative main leads Recommended Cell For high-drain RC use, a solid choice is the Molicel INR21700-P45B (4500 mAh, 45 A continuous): Molicel INR21700-P45B at NKON (EU) Series vs. Parallel — Quick Refresher Series (e.g. 2S = 1S + 1S) Two cells of 3.7 V / 2000 mAh connected in series give: Voltage adds up: 7.4 V (storage) / 8.4 V (fully charged) Capacity stays the same: 2000 mAh Note: 3.7 V is the nominal/storage voltage of a Li-ion or LiPo cell; fully c...

Quick reference for EdgeTX (and OpenTX) users on the RadioMaster TX16S: getting control-link geometry right at the servo arm and slowing down servo travel for scale or smooth control. Control Link Geometry The angle between the servo arm and the control rod has a huge effect on how linear (and how strong) the surface response is. Get it wrong and you end up with binding, lost throw, or unwanted differential. This short demo walks through the geometry visually: Control link geometry demo (YouTube) Slowing Down Servo Travel For scale models, retracts, flaps or just smoother flying, you can apply a delay or a slow rate to a servo channel directly in OpenTX/EdgeTX — no extra hardware needed. Step-by-step using mixer "Delay" and "Slow": OpenTX/EdgeTX — How to Delay and Slow Servo Travel (YouTube) Where to Configure Delay (s) — wait N seconds before the servo starts moving after a switch change. Slow Up / Slow Down (s) — limit how fast the servo can...

Notes on building Eclipson's 3D-printable Göppingen Gö 1 Wolf — a free vintage glider model — including the filament I used and the printing guide reference. About the Model The Gö 1 Wolf is a 1935 German training glider, available as a free 3D-printable RC model from Eclipson Airplanes: Gö 1 Wolf — Eclipson Airplanes (free download) I printed this one for a friend. Filament The recipe Eclipson recommends — and what I used: LW-PLA (lightweight, foaming PLA) for the wing and fuselage shells. Order example: PolyLight 1.0 LW-PLA Natural 1 kg (3DLabPrint, Amazon DE) Standard PLA for the structural and hardware-mount parts. Tip: LW-PLA must be dry — bake or dehydrate it before printing or you'll get poor foaming and weak parts. Printing Guide Eclipson's official printing details PDF (settings, foaming temperatures, infill, walls): Gö 1 Wolf — Printing Details (PDF) Build Photos

To fly drones or other unmanned aircraft (UAS) legally in Portugal, you need to register as an operator with ANAC, mark the aircraft, hold the right pilot competency, and get airspace authorization for camera/imagery flights. This is the current setup as of 2026. What changed: ANAC now runs everything through one unified platform — uas.anac.pt ("Voe na Boa") — covering operator registration (REPIF/TRACE), pilot training, aircraft registration and EASA airspace authorizations. The old separate AAN flow is now integrated. Step 1 — Register as an operator (ANAC) Go to uas.anac.pt → Register . Complete operator registration. You receive an operator number (REPIF/TRACE) — this is the EU-wide ID that must be displayed on every drone you fly. Mark the aircraft with that number (printed sticker, engraved, written — any visible permanent marking is fine). Flying without it can carry a fine of up to €2,000. Step 2 — Get your pilot competency Under the EASA Ope...

My current 3D printing setup for RC and hobby projects: which printer I run, which filaments I trust, and why filament dryness is the single biggest factor in print quality. Printer I'm running a Prusa MK4 and very happy with it. Previous printers I owned/built: Prusa MK3S+, Ender V3, plus several DIY builds. The MK4 is the one I keep coming back to for hobby work — reliable input shaping, easy Y-axis calibration, and good first-layer with the Nextruder. (Note: as of 2026, Prusa also offers the MK4S as a drop-in upgrade with the high-flow Nextruder; worth considering if you're buying new.) Filament Storage & Drying — The #1 Tip Removing humidity from filament makes a tremendous difference: cleaner surfaces, no popping, better layer adhesion. This is true for all filaments but critical for hygroscopic ones (LW-PLA, TPU, PETG, Nylon). I dry with the EIBOS Easdry / Series X dryer (ships from Europe). I store unused spools in EIBOS vacuum bags with desiccant...

How I bring up a new INAV-based fixed-wing build: choosing the flight controller, installing the configurator, flashing the board over DFU, and starting from a clean slate. Current versions (2026): INAV firmware 9.0.x ("Gallant Goshawk" generation) with INAV Configurator 9.0.x . Configurator and firmware versions must match the major version — don't connect a 9.x configurator to an 8.x board (or vice versa). 1. Choose a Compatible Flight Controller I default to Matek Systems boards — they're well-supported in INAV, have clean documentation, and the H7-class boards (H743 family) give plenty of headroom for the new INAV 9 features. Browse boards: mateksys.com · Full INAV-supported board list: INAV wiki — Boards 2. Install INAV Configurator Get the latest stable Configurator that matches the firmware you plan to flash: INAV Configurator — GitHub releases Windows 64-bit → win64 macOS Apple Silicon → MacOS_arm64 macOS Intel → MacOS_x64 Linux →...

How to get the full INAV OSD overlay (battery, GPS, artificial horizon, warnings) on the original DJI HD FPV Goggles V2 with a Caddx Vista air unit, by rooting both devices with WTFOS. Scope & status: WTFOS works for the original DJI HD FPV Goggles V2 + DJI/Caddx Vista Air Unit (the older 2.4 GHz / 5.8 GHz HD system). It does not apply to the newer DJI O3 / O4 Air Units or to Goggles 2 / Goggles 3 / Goggles N3 — those have a native MSP DisplayPort path. The WTFOS project is community-driven ( fpv.wtf , currently v2.3.0) and you root your own gear at your own risk. What You're Doing Rooting the goggles + Vista with the margerine exploit. Installing WTFOS (a community OS-on-top) on both. Telling INAV to send its native OSD via MSP to the air unit, which WTFOS overlays on the analog video feed. Reference Build Video Walkthrough of the result: INAV OSD over DJI HD (YouTube) Steps Wire MSP to the Vista. Check your flight-controller manufa...

Build log of a Dart Mini 2 — a small F3K discus-launch glider (DLG) from RCGlider.eu — assembled for a friend over about two weeks. Photos cover the whole process from carbon parts to maiden-ready airframe. About the Model The Dart Mini 2 is RCGlider.eu's compact F3K-class hand-launch glider. It's a moulded composite kit aimed at light-wind throwing and learning DLG technique without committing to a full 1.5 m F3K. The Build Took roughly two weeks of evenings. The kit comes well-prepped — most of the time is on: Servo install and linkages (4 micro servos: rudder, elevator, two wing surfaces). Pushrod routing through the boom. Receiver and battery placement for correct CG. Surface throws and exponential set up on the radio. Maiden Video Build Photos (36 images)

Quick note on getting the RadioMaster TX16S recognised as a USB-HID joystick in RealFlight on Windows 11 — the connection mode that historically worked silently on Windows 10 needs an extra step on Win 11. The Issue Plug the TX16S into Windows 11 with USB and pick "USB Joystick (HID)" in the radio menu — but RealFlight either doesn't see it or sees it with the wrong number of axes/channels. Fix Step-by-step video that walks through the radio settings, the Windows joystick calibration, and the RealFlight controller assignment: RealFlight + RadioMaster TX16S on Windows 11 (YouTube) Quick Recap of What That Video Covers On the radio (EdgeTX): SYS → Hardware → set USB Mode to Joystick (HID) (or set it to Ask and pick Joystick when plugged in). In Windows: Control Panel → Set up USB game controllers → make sure the TX16S shows all the axes moving when you wiggle the sticks. In RealFlight: Simulation → Select Controller → pick the TX16S → run the cali...

An overview of the RC stuff I'm actively flying, building or planning to buy — radios, drones, planes/gliders, boat, and the 3D printer that supports it all. I've been in the hobby since 2004; this is just the current line-up. This list does NOT include older models I've owned in the past — I started in 2004. 🛥 Boat MicroMagic v2 — a keeper. Small, easy to store, surprisingly fun on a sailing pond. 🛸 Drone DJI Avata 2 — current cinewhoop / FPV drone. ✈️ Planes & Gliders In active use Dreamflight Alula-TREK — product page . I'll keep this one forever; flies brilliantly in everything from calm air to slope. Dreamflight Libelle DLG — product page . Offered by a friend; flies well as a learner DLG. 3DLabPrint Piper J-3 Cub — product page . Maiden done — flies very well, gentle and scale-looking. In the workshop / queue ArtHobby SKUA — product page . Currently building. 3DLabPrint P-51D Mustang — product page . Maiden ...

Why I picked the AtomRC Swordfish over the Volantex Ranger 2400, the flight controller I'm using, and the high-energy 21700 Li-ion battery setup for long endurance flights. Why the Swordfish (and not the Ranger 2400) I built a Volantex Ranger 2400 first and ran into three things that bugged me: Wing connectors carry the flap and aileron servos directly — every wing remove/install stresses tiny pins. Tight internals — there's very little space to lay out a clean FPV / INAV stack. Wooden centre plate — fine for stock electronics, awkward for a modern flight controller. I designed and printed a replacement plate; happy to share the STL — DM me. After watching a few build comparisons on YouTube I switched to the AtomRC Swordfish. The Plane 1200 mm twin-motor EPP fixed wing — light, robust, FPV-ready out of the box. AtomRC Swordfish 1200 mm — Banggood Flight Controller I already had the Matek F722-WPX from another project, so I'm using that...