Aut cum scuto aut in scuto
Seamless metal pieces from r/interestingasfuck
I have seen some precision machining in my time...but this....this take the cake. I showed this to my boss who is a Retired Navy LDO Captain, he could not believe it. And he was in charge of overseeing all maintenance on the Atlantic surface fleet!
That's crazy.....I wonder how many times it took to get that right....
E.D.M. Then polish.
Air bearing (actually Nitrogen) machines. My micrometer sets measure to.0001".These these machines can get down to low millionths of an inch.No mechanical bearings can match this degree of accuracy.