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Comment by mikewarot

12 days ago

Having made an 4 year excursion from IT into the world of making gears, I can attest that what seems like something fairly simple from the outside really isn't.

Just like a bearing, gears (ideally) have a rolling contact. The smoother and harder the faces the better, until you get to the point where fractures and spalling occur. The best gears are cut, sent out to be hardened via heat treat, then ground (with "superfinishing") to exact size. As with bearings, you have to get the size just right for long life.

Making featureless metal balls seems very easy, they have only one dimension and are perfectly symmetric.

.. until you realize that:

- they have extremely tight tolerances - they function together, a single defect one ruins the whole assembly - you have to make millions of them for cheap

Some things are deceptively hard. For a related fun fact, check out China's ballpoint pen adventures.

  • >China's ballpoint pen adventures

    True. Though they've moved up in the world since then. They now have their own semiconductor fabs. Chinese industry of today is way more advanced than the China of the 90's making low margin nick-nacks.