Horological Meandering

SJX
[Purist]
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Testing movements VS watches; historical reasons for COSC

The COSC tests are conducted on movements, rather than watches; there is no requirement that the movements have to be finished. Even with the change in COSC procedures, an unfinished movement with the complication module could be tested. I personally do not believe that the results of the test are a gauge of the performance of the watch on someone's wrist. A movement will undergo a lot of handling/finishing/casing up, after the test and this could affect its timekeeping, although it is unlikely because modern movements are just too good.

That brings me to my second point, which is the changed nature of watch movements. The history of COSC is simple, the body is the successor to the famous observatory tests of the 19th and 20th century, in fact COSC was former by a merger of the bodies that did the observatory tests. These tests were conducted in a time when watchmaking technology was no where near as advanced as it is today.

Back then an expensive watch from Patek or AP would probably keep better time over a long period than a cheap watch, because of the materials used and the construction of the movement as well as its finish. Movements that were observatory certified were truly fine movements; look at the examples of such movements today and you will usually find very fine construction like a big balance wheel, an elaborate regulator, a finely finished escapement and of course a Breguet overcoil.

Today, cheap mechanical watches keep just as good time as a 'fine' watch, due to the advances in manufacturing technology and the immense volumes of production; the average ETA movement is a brilliant piece of engineering. COSC does not prove a watch is a better timekeeper or a better quality timepiece - in other words it does not mean much, in my humble opinion.

The same could be said for the Geneva Seal. Once upon a time the requirements of the Geneva Seal meant only the best firms with the most skilled watchmakers could create watches that met those criteria. Today a good amount of finishing requirements can be done by machine, or at least with the help of machines, so the presence of the Geneva Seal does not prove that a watch is hand-finished to the highest standard. Admittedly, I believe brands like Patek and Chopard still do much of the finishing by hand, but I would not be surprised if some other brands that tout the Geneva Seal on their movements actually enlist substantial help from automated processes to meet the requirements.

- SJX

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