Internal Combustion Engine
I just built an engine for my car. One thing I gained an appreciation for was how CHEAP cars and engines are. There's probably nothing else with as precise machining that is as inexpensive.<p>Engine cylinders are honed to accuracies that are less than 1 thousandth of an inch. Crank journals as well and rod journals. This is all precise machine work with metal. I use inches here because in machine work thousandths of inches is the language du jour. Transmissions are similar works of very precise and clean machine work.<p>The distance between a crank bearing or rod bearing is less than 2 thousandths on modern engines. A small amount of oil in that tiny space is all that keeps your engine from having metal on metal seizure.<p>So one would think that when EVs reach the same scale they will be significantly cheaper than ICE vehicles.