eli5 how is the ball in the tip of the Pen is made/manufactured, how something can be made so small, yet so perfect?

Question

like, it is not only about ball of the Pen, but also about many things, like how small springs are made, and etc.

In: 8

Answer 1

Are links to YouTube allowed? If not, search YouTube for “how it’s made ball bearings”. I don’t know how to get any more ELI5 than that.