My favorite movement hands down, as nice as challenging as a service.
Here is the all time classic Zenith Cal. 400, known as first automatic chronograph, which gives it its name, “El Primero”.
Given its extremely high beat @ 36.000BPH, lubrication is crucial on this one, doesn’t leave the slightest room for error.
Some pics of it, disassembling first (it was full of oil, where it shouldn’t be any) and totally disassembled and inspected, ready to be reassembled.
Here is the all time classic Zenith Cal. 400, known as first automatic chronograph, which gives it its name, “El Primero”.
Given its extremely high beat @ 36.000BPH, lubrication is crucial on this one, doesn’t leave the slightest room for error.
Some pics of it, disassembling first (it was full of oil, where it shouldn’t be any) and totally disassembled and inspected, ready to be reassembled.
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