Intro
While the watchmaking industry taught us that heritage is a Swiss affair, the last 13 years since the media went online suggest that the foothold is widespread across Europe, with Austria and Germany often leading the way, and the Brits priding themselves on several remarkable patents.
A. Lange & Söhne and Nomos Glashütte well exemplify the German watchmaking school from opposite ends of the spectrum: the former is pure tradition, while Nomos fosters the postmodern era. They are the Saxon heritage standard-bearers, challenging the Swiss-made industry.
However, don’t stop in Glashütte; turn your heads to Bavaria, where unexpected manufacturers uphold a tradition so old that we thought it had long since disappeared. There, you’ll realize that a small company is pushing the envelope of a once-forgotten, yet precision-setting timepiece: the pendulum clock.
When Erwin Sattler and his wife Viola founded the eponymous brand in 1958, our society and watchmaking were very different from today, and the pendulum clock was still a sacred cow, as evidenced by its presence in the most luxurious villas, including those stretching from the North to the South of Italy.
Erwin Sattler, a brand I got into while attending Baselworld, suddenly caught my eye since I never thought there could be such a wide audience looking for the ultimate pendulum clock that Erwin Sattler had long promoted, against all market odds.
While Indie watchmakers made Swiss Made great again, whether in wristwatchmaking or in time machines (read L’Epée 1839), Erwin Sattler stands as the promoter of a seemingly forgotten product category, to the point of deserving the “Make Pendulum Clocks Great Again” moniker.
A few miles outside Munich
A few miles outside Munich, in Gräfelfing, you’ll find the Erwin Sattler small yet highly productive manufactory, whose core business is not restricted solely to pendulum clock design and assembly.
Over the years, it has expanded its portfolio to include more product categories, such as table clocks, luxury watch winders, and wall clocks, ranging from smaller, simpler regulator pulley models to precision pendulum clocks so monumental that they push timing accuracy to unprecedented levels by combining the finest, long-established watchmaking with state-of-the-art technology.
However, Erwin Sattler moved further, extending its product portfolio to wristwatches by introducing Haute Horlogerie timepieces like the jaw-dropping Regulator 1920 in gold, as well as more affordable yet attractive models such as column-wheel chronographs and time-only models.
From this perspective, this German powerhouse has followed an unconventional product development strategy compared to its peers.
The Core Business: Pendulum Clocks
The pendulum clock business holds centre stage and is the undisputed core, extending from classic 60-to-130 cm regulator pulley models to industry-leading precision pendulum clocks that embody the brand’s unique value proposition.
The former category collects pendulum clocks that pay homage, for instance, to “Vienna”-style clocks, which were very popular between the mid-nineteenth century and the first half of the twentieth century.
As the smallest model, the Graziosa 60 comes standard with remarkable specs, including four ball bearings and nine jewels; the pulley itself rotates on ruby bearings.
When fully wound, a Graziosa 60 can run for fourteen days; its design is sleek and minimalist, yet stylish and well-conceived to fit as many surrounding scenarios as possible, seamlessly. For your record, an ordinary regulator pulley clock can achieve an average accuracy of 10 seconds per week.
Erwin Sattler’s Haute Horlogerie department: the Precision Pendulum Clocks
Here is where things get serious. Erwin Sattler developed an unparalleled range of so-called precision pendulum clocks, elevating Huygens’ invention to heights never before achieved. Forget those clocks you grew up with; get ready to step into the Formula One of pendulum clocks.
The Classica Secunda 1995 M is an excellent example of how Erwin Sattler combined watchmaking’s finest with advanced materials and metrology to achieve the highest possible accuracy.
The escapement, developed by George Graham in 1715, was built on the 1675 device originally engineered by astronomer Richard Towneley.
It is a proven solution in pendulum clock making, as it solves two issues often associated with lever-escapement-powered pendulum architecture: recoil and friction.
In pursuit of extreme precision
Sattler Calibre 1965 therefore adopts a Graham escapement, which allows the pendulum to swing freely and lays the foundation for enhanced precision, which the brand claims falls in the one-to-two seconds per month range.
A comparable mechanical wristwatch is a latest-gen Spring Drive calibre 9RB2 Grand Seiko, whose declared accuracy is ±20 seconds per year.
However, you won’t get there by solely relying on a Graham escapement; here is where things get interesting, and a closer look at a pendulum’s oscillation period formula kicks in:
To ensure the rod’s oscillation period is constant, engineers must keep the length L constant. To mitigate any variation, it is paramount to keep the ambient temperature under control. Thus, Erwin Sattler’s engineers adopted an iron-nickel alloy called Invar for the pendulum rod to ensure exceptional dimensional stability over the -20°C to 230°C range.
However, that’s not enough; you still need a device to counteract the tiniest possible variation, which makes a pendulum’s rod slightly expand or contract when a small temperature change occurs. That’s where the compensation device at the bottom end comes in: it precisely shortens or lengthens the “L” in the formula, ensuring isochronism.
It’s not over yet; another parameter that affects isochronism is air pressure. A smaller variation results in a change in air density, which in turn leads to higher or lower friction, slowing or speeding up the pendulum rod and, again, affecting isochronism.
Air pressure compensation is managed by a barometer located at the top end. It is a Riefler barometer, named after the German physicist Sigmund Riefler, who developed it in the late 19th century.
It is an aneroid, hence fluid-free, device consisting of five metal capsules that expand or contract and are connected to a counterweight. Again, pressure variations are compensated to keep the oscillation period T under strict control.
The Sattler 1965 Calibre
The Sattler 1965 movement is partially visible through the dial; the aperture at 12 o’clock reveals the Graham escapement and gold-plated gear trains, with a three-arm-designed bridge on top.
Seconds, minutes, and hours “pomme” hands are hand-curved and then blued.
The winding mechanism includes a 3.1kg cylinder connected to a pulley that rotates on ball bearings, providing a 30-day power reserve. According to Erwin Sattler, it takes approximately two years to manufacture all the parts that make a Classica Secunda 1995 M.
Classica Medium Limited
The brand’s step into wristwatches was quiet yet convincing. While pendulum clocks are the brand’s comfort zone, wristwatches require a gradual approach given the category’s fierce competition and product mix.
All Erwin Sattler wristwatches usually come in small quantities, and the limited-edition models are indeed produced in strictly numbered series.
Classica Medium Limited is a great example, since just 50 pieces will roll out the assembly line. It’s very much Erwin Sattler in everything from the dial typography to the “pomme” hands, which build the Erwin Sattler logo. The round case showcases a vaguely baroque style when seen from its side or the lugs, which bring me some old-gen Breguet Marine vibes.
However, don’t get fooled by the pictures: its 39.00 mm-diameter case is just 10.50 mm thick, and the bronze dial with Roman numerals and a railroad minute track, without a date, is as neat as it gets, in true Erwin Sattler style.
Under the hood sits an externally sourced STP (Swiss Technology Production) calibre, namely the STP1-21 variant, all in all a well-finished take on the ETA 2824-2, customized to the brand’s own specifications, offering a 44-hour power reserve when fully wound. It is not an in-house calibre, and nobody is asking for it, but a tried-and-tested mechanism powering a 50-piece limited edition watch, whose listed price stops at a reasonable $4,260.
Photo credit: Erwin Sattler)
Gaetano C @Horbiter®
