Patek Philippe

ei8htohms
8555

• Show profile
• Show other posts

it would seem largely contrary to Patek's design philosophy as I understand it

Hi parkavenue740,

The only companies that currently manufacture movements with fusee and chain mechanisms are Lange and Cabestan to my knowledge.  Lange was the first company to manufacture a wristwatch with a fusee and, while it may be true that marine chronometers continued using them to some extent until the 1970s (I really don't have any idea, but I'll take your word for it), they fell out of fashion for all other purposes in portable mechanical timekeepers at least a hundred years or so before that.

Fusees attempt to regulate/stabilize the power flow as near as possible to the source (the mainspring/barrel) in an effort to keep balance ampltiude consistent and thereby improve the consistency of the rate over the run time of the watch.  Back when mainsprings were of questionable consistency, this was a critical concern as the amount of power delivered when fully wound was huge compared to that available even after a few hours.  Fusees were introduced to counteract this problem, but they are fantastically complex (involving hundreds of tiny parts) and must be carefully designed for a given movement or even a given mainspring's power curve in order to do their job very well.  Escapement design was not as thoroughly optimized at that time either, making the consistency of the power flow available at the escapement more critical to good timekeeping and hairspring/oscillator designs also had greater inherent isochronism errors, making the ultimate rate of  the watch much more dependent on smooth power flow than they are today.  A the time that they were in fashion, fusees did the job better than any other alternatives despite the difficulties present in manufacturing them.

As technologies have evolved, we have better mainsprings, better escapements and better hairsprings, and the result is more consistent power flow, better escapement response across a wider range of power inputs and better isochronism across a wider range of amplitudes.  All of this adds up to fusees not making any sense from any practical standpoint.  Lange very clearly understood this when they came out with the Pour Le Merite and undertook the fantastically difficult and labor intensive task of putting a fusee and chain into a wristwatch purely for the artistic/artisanal/craftsmanship sake of doing it.

Patek's engineering and design is generally speaking driven by functional performance enhancing initiatives, whether they be actual rate performance gains, greater ease of serviceability, greater longevity of the various components or increased reliability.  Sure, they polish up the bits nicely and decorate all the little wheels and nubbins, but you won't find too many superfluous chatons or archaic swan's neck regulators in Patek Philippe movements.  It's just not what they're about (and thank god for that IMHO).

_john