Design Blueprint: A Wire-Arc Additive Machine for Orbital Fabrication of Steel Frames: Arc Power, Deposition and Shielding Budgets

Design blueprint derived from the source paper (DOI 10.5281/zenodo.24185193): This paper presents a computed design study, SIMULATED, NOT MEASURED, for steel frame nodes, trunnion blocks and other bulky low-precision structure in orbit, using 1.2 millimetre steel welding wire on spools. The operating principle is distinct from neighbouring production methods: a gas-metal arc struck from the feed wire itself deposits steel bead by bead into near-net shapes. Wire is dense, safe and cheap to launch compared with powder, the arc supply is mature welding equipment, and deposition rates exceed those of powder-bed processes by an order of magnitude. The costs are surface roughness, residual stress and a shielding-gas supply that must be budgeted as a consumable rather than assumed. Sizing follows from budgets computed in the accompanying script rather than from analogy with terrestrial equipment. The headline figures are a specific energy of 1.74 megajoules per kilogram of product, an installed electrical power of 5.68 kilowatts, a production rate of 11.8 kilograms per hour, and an annual throughput of 9.32e+04 kilograms over 330 operating days. Rejecting 3.13 kilowatts of waste heat at 335 kelvin requires 4.97 square metres of radiator, a photovoltaic supply requires 13.9 square metres of array, and the installed mass is 564 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.