Design Blueprint: A Friction-Stir Additive Machine for Orbital Fabrication of Large Aluminium Plates: Torque, Travel and Energy Budgets

Design blueprint derived from the source paper (DOI 10.5281/zenodo.24185036): This paper presents a computed design study, SIMULATED, NOT MEASURED, for large flat structural plates and tank wall sections too wide for powder beds in orbit, using aluminium 2219 plate feedstock and shoulder stock. The operating principle is distinct from neighbouring production methods: a rotating non-consumable tool plunges into stacked plate and traverses, plasticising and forging the metal in the solid state as it goes, so a large plate is built by stirring rather than melting. Peak temperatures remain below the melting point, porosity characteristic of fusion is absent, and the feedstock is ordinary plate, the cheapest form in which aluminium reaches orbit. The governing variables are spindle torque, rotation rate and travel speed. Sizing follows from budgets computed in the accompanying script rather than from analogy with terrestrial equipment. The headline figures are a specific energy of 5.76 megajoules per kilogram of product, an installed electrical power of 15.4 kilowatts, a production rate of 9.6 kilograms per hour, and an annual throughput of 7.6e+04 kilograms over 330 operating days. Rejecting 8.45 kilowatts of waste heat at 330 kelvin requires 14.3 square metres of radiator, a photovoltaic supply requires 37.6 square metres of array, and the installed mass is 1.16e+03 kilograms. Moving feedstock from a 400 kilometre to an 800 kilometre orbit costs 217 metres per second of velocity change. The study is a computed study with no targeting or weapon application; it concerns civilian production equipment only, and none of its figures is a measurement. Status: DESIGN BLUEPRINT — SIMULATED, NOT MEASURED — NOT BUILT. All numbers are simulated values from the source paper's computation, deposited with this blueprint as compute.py and results.json. AI-use disclosure: Dave, an AI research system, assisted with the computation and drafting under the author's direction; author of record William Alexander Aldred.