I’m going around in circles,

One side fast and one side slow,

Always in a hurry,

Always a little behind,

I never knew that I

Key to determining time.

I am twisted to the left

While I am turned to the right,

While my inner

They are packaged really tightly.

It turns out I have talent

For being in the middle,

I was told I have great balance

With slightly different entrances.

It is not that difficult,

I do it without thinking,

All because of two great minds,

They were forged from metal.

I am not a locomotive,

Even though I am a train,

I am not a solar system,

And yet I have planets in my head.

I am really just different,

Like your brother or sister,

Call me differential,

But no first name please, just Mr.

Ahh, it’s good to be back! And why not start with a fun little ditty about one of the coolest forms of gear system that seems easy to understand but very difficult to build: Mr. Differential! That sounds like a fun character for a t-shirt. Maybe today’s main brand would like to collaborate on a design for some giveaways? I have some ideas!

All joking aside, the differential is a very specific system that can be used for a variety of purposes. However, in a clock with two separate gears, it attempts to average two inputs into a single output. This output is the mechanical average of the speed of the inputs (two gear trains governed by two slightly different escapements) and should therefore remain more constant even if the underlying gear trains change pace.

Developing this system is difficult not only because many critical components are very small, but also because it requires a lot of mathematics and careful planning to make it work exactly as intended.

If you then impose further tight constraints on this design, the level of difficulty increases almost exponentially. Which of course brings us to Czapek and Bernhard Lederer, the brilliant minds behind the stunningly symmetrical Place Vendôme Complicité, a double-geared masterpiece that debuted at Geneva Watch Days 2023.

Czapek Place Vendôme Complicité

What is this watch at its core? If you don’t get lost in the mechanics on the dial side (if you don’t, you’re probably not reading this), the Place Vendôme Complicité is a “simple” round watch that displays hours, minutes and seconds, and has a small power reserve indicator at six o’clock.

It is manually wound, has a 3-day power reserve and is a bit large at just under 42 millimeters in diameter. However, we still have no idea what this watch is and, like an iceberg, the best bits are just beneath the surface.

Based on a new movement, the Calibre 8, the Place Vendôme Complicité uses two mainsprings in series to drive two sets of gears connected by a central differential. This results in two balance wheels on the dial side, visible at 4:30 and 7:30, and two escapements flanking them respectively at three and nine o’clock.

Further up the dial we find mirrored fourth wheels that meet the differential in the center at twelve o’clock.

This perfectly symmetrical layout is highlighted under two large, layered sapphire bridges that support everything from the escape wheel to the differential. The two balance wheels are supported by more typical skeletonized steel bridges, in the same style as the previous Place Vendôme pieces.

While this floor plan is familiar to the entire collection, it was a headache early on in the development of these pieces because the well-known mantra of the real estate industry applies here too: location, location, location.

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