Hacker Remix
Swedish Exports of Ball Bearings
34 points by zeristor 4 hours ago | 5 comments
mikewarot 3 hours 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.
mongol 2 hours ago
Reminds me of SKF's sponsorship of the new Marble Machine by Martin from Wintergatan
See for example this video, how to choose your ball bearing
usrusr 2 hours ago
Setting away Mosquitos (the real Wunderwaffe of that war) for freight runs (and for stuffing the occasional Nobel Price physicist in the bomb bay) tells a rather different story about the importance of swedish-made ball bearings for UK arms production:
pomian 1 hour ago
Great article about the Mosquito! Thanks.
That's yet another HN rabbit hole!
It confirmed a friend's war story I heard, first hand - about escaping from a German POW camp near Berlin - then proceeding to Copenhagen, with the help of the Danish underground, stealing a rowboat from a German yacht, rowing to Sweden at night. The wounded one stayed in Malmo, the other two continue to Stockholm. There they went to they Polish embassy. One stayed there, the other was sent to Scotland that night in a mosquito. (Later he went to London, then dropped by parachute behind enemy lines.) Now it's the first time I read a story to verify that other first hand account! (I obviously summarized an amazing tale.)
emmelaich 24 minutes ago
Similar dynamic to YKK's dominance of the zipper industry.
Now challenged by a few look-alike Chinese companies.