Eli5: On a production line, how do they make a car, plane or anything else be identical from one another without differences?

Question

Eli5: On a production line, how do they make a car, plane or anything else be identical from one another without differences?

In: 6

Answer 1

They don’t. They’re all slightly different, but mostly the same.

They specify that the components be made within a certain tolerance for dimensions and other properties. They are designed that as long as the parts are within those tolerance the composite machine will work as intended. You can replace any part with another part that meets the original specifications and it’ll work.