A 2 m fixed-wing UAV prototype built around a plywood skeleton, foamboard skins, 3D-printed fittings, and ArduPilot electronics.
This repository documents the work of adapting an existing aircraft design to available materials and workshop processes. It contains the assembly CAD, laser-cutting layouts, printable parts, wiring references, and illustrated build guides used for the prototype.
CAD illustration from the R6 guide. Blue shows foamboard and grey shows printed components. Physical acceptance and flight testing remain open.
R5G airframe assembly guide · R6 foam, servo, and electronics guide · Download cutting packages
The starting point is the source CAD and build by Michael Rechtin. This adaptation keeps the source part identities so a builder can trace a cutting profile back to its installed part.
- A 37-piece, nominal 6 mm plywood set includes reinforced outer wing ribs and a motor firewall blank for marking and drilling against the actual motor.
- R6 develops the wing, fuselage, and V-tail skins for nominal 5 mm foamboard, with separate cut, score, and marking layers.
- Four smaller plywood jobs provide an alternative layout for the complete set. Individual replacement files support repairs without cutting a second aircraft.
- The guides connect part identification, hand finishing, assembly order, servo linkages, wiring, configuration, and physical checks.
Read the design notes for the manufacturing decisions and their limits.
R5G and R6 describe different parts of the same build. R5G is the airframe baseline; R6 is the newer foamboard and installation guide for that skeleton.
| Area | Current entry | What it contains |
|---|---|---|
| Airframe assembly | R5G guide | 74 pages of part identification, fitting, assembly, wiring, and checks |
| Foam and installation | R6 guide | 36 pages covering three 1000 x 600 mm foam sheets, CH hand fitting, servos, and electronics |
| Plywood | Cutting instructions | Four sequential jobs or one full master, 37 pieces total |
| Foamboard | R6 plans and previews | 5 mm foamboard, 1:1 millimetres, separate laser layers |
| One DXF per part | Plywood, 37 files and R6 foam, 21 files | Separate cutting files with part names, quantities and retained laser layers |
| Replacement parts | Recuts and A10 tip templates | Ten replacement profiles, including corrected A25/A48 ends and the A10 robust-tip option |
| CAD | Assembly and individual STEP files | Finished parts, laser stock blanks, and secondary removal geometry |
| 3D printing | STLs and print notes | Current fittings and reference slicer recipes |
| Build records | Data notes | Part lists, estimated mass data, and uncompleted physical checks |
The CH front underside uses a continuous fitting blank with manual grooves and local relief cuts. Read the short CH guide before forming it on the existing frame.
The 2026-11-06 A25/A48 end profile follows the black workshop outline. Both upper shoulders are inset to the original notch inner edges, while the lower projections and overall dimensions are retained.
The version guide explains superseded files and how to use the two PDFs together. Older releases remain available for traceability.
- Read the R5G guide for the skeleton and the R6 guide for new foam skins and installation.
- Choose the plywood, foam, or print instructions before opening a manufacturing file.
- Measure the actual stock and machine envelope. Prove a fit coupon and dry-fit the relevant interfaces before committing the full job.
- Record the physical results in your own build log. Use the acceptance checklist as a starting point.
DXF files use millimetres at 1:1 scale. STEP files open in CAD software such as FreeCAD or Onshape. STL files need a slicer; filenames describe reference settings but do not embed them.
The project is in fabrication and integration. Digital geometry and layout checks are documented in the build handoffs. Completed cutting and printing do not establish acceptance of the assembled aircraft.
Physical fit, cured joints, control loads, propulsion current and temperature, final mass and centre of gravity, failsafe, and pilot acceptance remain unrecorded as complete. Landing gear is a later build stage. Flight performance and autonomous operation have not been demonstrated in the published records.
Mass figures in the repository are estimates from assumed material densities. No measured aircraft weight, endurance, or flight-ready configuration is claimed. See the validation status before using the plans.
Adaptation and build documentation: Abhinav Pullela / mcarkade. Original CAD and construction source: Michael Rechtin. See credits and reuse for source links and the current licensing status.
Corrections, reproducible fit reports, and documentation improvements are welcome. Read CONTRIBUTING.md before proposing manufacturing changes.