You would typically use five axes for complex parts unless there was a compelling reason not to. Interestingly, as I am buying one at the moment (our first) I had a chance to talk to different machine shops about their different brands here in China. They alleged that foreign dual use export restrictions have resulted in a situation where China's local five axis machines are now both cheaper and more accurate than the available foreign imports (source: major prototyping shop, machine count >20, machine brands 3x, 5 axis count 10+). This was supported by the second shop I visited who also said they will no longer buy imports.

You're joking but interestingly Tesla at the Battery Day presentation revealed a giant injection mould to make the aluminium chassis for one of their cars, which will simplify the manufacturing process.

So we're going into uni-body territory but with a faster, simpler process than milling/printing. If Apple is happy buying thousands of milling machines for laptops and phones, a chassis injection mould might be the process they'd need to break into the car space.

"a bicycle for the body"

> single block of aluminum

iCar

Space gray, chamfered edges, 115 hp, 4 wheels

$100,000