I understand that this hairspring in the (beautiful) Zeitwerk movement is free sprung. However, I don't quite understand how this works. I know that having a free sprung balance means that the length of the hairspring is not adjustable via a regulator. Si...
Just to clear up/reiterate on terminology (and correct me if I'm wrong) - in the old days before freesprung balances are invented, mechanisms like the swanneck are used to finely adjust the beat rate. Hence, for non-freesprung Lange watches we refer to it...
i.e. when the "tick" and "tock" of a watch are of different timing lengths, they need to be adjusted so they are equal duration. This can be fixed by adjusting the position of the start of the hairspring (the stud). A watch can be at the correct beat rate...
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