Noctua is a well-respected manufacturer of PC case fans and similarly unromantic cooling components. But unromantic does not mean uninteresting, as demonstrated by a lengthy article the company published explaining why it takes so long to release any given fan in black after the company's house tan. At the tolerances involved, injection molding "is less like making ice cubes and more like baking a complex soufflé where every degree of temperature and milligram of ingredients matters." Even pigments change all the calculations. Achieving such small tip clearances is essentially at the absolute limit of what injection moulding can consistently reproduce. … Colour pigments impact the injection moulding of these high-precision fans because the pigment particles behave like tiny solid fillers inside the melt. Their size, surface area, and thermal behaviour directly influence how the polymer flows into the mould, as well as how it cools and solidifies.…