How would extrusion work well in an orbit without support? I would say, over the time of the orbital period there would be 4 sheering events. The extruded piece, if extruded over periods of time comparable or longer than the orbital period, would contain micro-defects due to unequal forces acting on the piece during the orbit. I'd say you'd have to be above LEO and have extrusion time &lt;90 minutes to get usable results (for pieces PE over 10m in length, look up the thermal and glass transition properties of PE, Steel is even worse and needs more time. Correct me if I am wrong).