Kaworu Chang shows how 3D printed an ultra-lightweight upper receiver using SpiderMaker carbon fiber nylon PA-CF for use on an airsoft P90... "Nozzle caliber 0.4mm, nozzle 240 degrees, bed 60 degrees, fan 50%, speed inside 80 outside 40. I only used 2 walls and only used 10% fill, maybe because of that it feels a bit soft