a factory of the 6 sciences pack (red, green, blue, black, purple and yellow) to focus on others aspects of the game. It just need the iron (4 belts) and copper (3 belts) plates, the stone, the carcoal, water and petrolum. That blueprint is for midgame (red belts and blue assembling machine) but you can update it all (with blue betls and yellow assembling machine to reach 1s/s !