Grand Seiko Mechanical Hi-Beat GMT “Yuka Momiji” SBGJ273

In Japan, the seasons are much more than the schedule by which the land cools and warms. They are woven into the fabric of daily life, and pausing to appreciate the unique charm of each season is as natural as can be.

This spirit imbues the latest Grand Seiko Hi-Beat GMT, which comes with a dial that expresses a very specific scene of Japanese autumnal beauty. The new SBGJ273 is inspired by yuka momiji, the quiet beauty one might encounter in a traditional Japanese building when the ebullient reds of the changing maple leaves outdoors reflect off the lacquered floors within. The floorboards become illuminated with vivid colors, all the while maintaining the definition of their striated form.

Grand Seiko red-dial watch SBGJ273
Grand Seiko red-dial watch SBGJ273
Grand Seiko red-dial watch SBGJ273

With a stripe pattern polished to a bright sheen, the dial of SBGJ273 shows a rich range of red colors, reflecting the subtle variations among the fiery leaves and the dark reflective floorboards themselves, expressing yuka momiji. The depth and complexity of the dial are complemented by the GMT hand, which takes on a vivid gold color that adds to the feeling of autumn while ensuring high contrast and easy legibility. This combination of beauty and ease of use continues with the diamond-cut hands and indexes, which reflect light pleasingly while ensuring that the watch can be read even in low light and without the use of luminous material. Like all Grand Seiko GMT watches, this new timepiece has an independent local hour hand, allowing the time to be changed easily, forward or back, as one goes about their travels.

In spirit, this watch follows the limited-edition SBGH269, which utilized the same dial pattern and color palette, albeit with a different case and without a GMT function, as well as the SBGJ271 of earlier this year, which expressed a similar concept – that of bright white snow reflecting off of lacquered floorboards.

The SBGJ273 has a round shape that has become a classic of Grand Seiko mechanical watchmaking. Influenced by the first Grand Seiko design from 1960, it measures 39.5mm in diameter and 13.9mm thick, with mid-century good looks reinforced by a prominent box-shaped crystal, an elegantly rounded mid-case, and faceted lugs with Zaratsu polishing.

Grand Seiko SBGJ273 powered by Hi-Beat Caliber 9S86

Powering the SBGJ273 is the Hi-Beat 36000 GMT Caliber 9S86, which features automatic winding and a power reserve of 55 hours. Thanks to its rate of 10 vibrations per second, Caliber 9S86 enjoys excellent stability over time as well as resistance to external factors such as shocks. Tested under the Grand Seiko Standard, Caliber 9S86 provides an accuracy of +5 to -3 seconds per day.

Grand Seiko SBGJ273 red dial watch on wrist.

The SBGJ273 will be available starting September 2023 at Grand Seiko Boutiques.

Hi-Beat 36000 GMT
SBGJ273

Grand Seiko Caliber 9S 25th Anniversary Limited Editions SBGM253 and SBGJ275

In 1998, Grand Seiko launched the Caliber 9S, the movement platform upon which its mechanical watchmaking in the modern era would be built. This platform would eventually give rise to a new line of Hi-Beat movements, a revolutionary escapement, quite a few GMT models, and, just this year, Grand Seiko’s first mechanical chronograph.

To celebrate, Grand Seiko is introducing two new Caliber 9S GMT models that pay homage to Iwate, the birthplace of this movement family and where all Grand Seiko mechanical movements are assembled by hand. One in the Sport Collection and the other in the Elegance Collection, they each lift the imagination skyward above the soaring peak visible from the windows of the Grand Seiko Studio Shizukuishi.

Grand Seiko reference SBGM253
Grand Seiko reference SBGJ275.

In SBGJ275, a blue dial illustrates a rarely seen sea of clouds at daybreak when humid air forms dense clouds that overlap with one another. The blue color is inspired by the sky over Mt. Iwate when it is blanketed by these clouds. Thanks to the rotating sapphire crystal bezel and the caliber 9S86 with independent local hour function, this GMT can display the time in three places at once. On the back, an anodized titanium oscillating weight in a light shade of blue complements the beautiful dial. Though not a diver’s watch, more than ample water resistance makes it ideal for those whose travels may take them to all kinds of environments. It also marks the first time that a Grand Seiko mechanical watch with water resistance to 20 bar has had an exhibition case back.

SBGM253, the other new anniversary GMT, is in a classic shape from the Elegance Collection. Running on the 9S66 automatic movement, which beats at 28,800 vph and provides a full three days of power reserve, or 72 hours, it has conservative proportions and subtle styling. As with the Sport Collection GMT, an exhibition case back provides a window to view a special rotor treated with the same anodization process, only this time, it creates a lovely Grand Seiko Blue.

The dial has a sunray pattern in a beautiful shade of light blue that recalls the clear sky as seen from the peak of Mt. Iwate, and around the dial, a 24-hour scale is printed in a darker but harmonious shade of blue, ensuring that this GMT is supremely legible while also demonstrating the subtlety of a modern Grand Seiko classic.

SBGM253

Each new GMT comes with a stainless steel case and bracelet. The Elegance Collection Caliber 9S 25th Anniversary Limited Edition SBGM253 is a limited edition of 1,700 and will be available at Grand Seiko Boutiques and select retail partners worldwide beginning in October 2023. The Sport Collection Caliber 9S 25th Anniversary Limited Edition SBGJ275 is a limited edition of 2,000 that will be available at the Grand Seiko Boutique Online beginning September 2023 before availability is extended to physical Grand Seiko Boutiques and select retail stores the following month.

Elegance Collection – Limited Edition of 1700
Automatic GMT SBGM253
Sport Collection – Limited Edition of 2000
Hi-Beat 36000 GMT SBGJ275

Grand Seiko Elegance Collection Ladies STGK019, STGK021, and STGK023

At Watches & Wonders Geneva, Grand Seiko expanded its assortment of ladies’ mechanical watches with the addition of three new stainless steel watches featuring silky dial patterns in different colors and the added sparkle of diamonds. They are small and elegant watches, measuring 27.8mm in diameter and 11.2mm in thin, yet within each is the powerful essence of high-end mechanical watchmaking from Grand Seiko.

They include the STGK019, with its diamond-set bezel and hour markers; the STGK021, with its diamond-set bezel; and STGK023, with its smooth steel bezel and diamond hour markers. For both STGK019 and STGK021, the number of diamonds set on the bezel is 45.

Grand Seiko STGK019 ladies watch with pink dial.STGK019
Grand Seiko STGK021 ladies watch with white dial.STGK021
Grand Seiko STGK023 ladies watch with blue dial.STGK023

Inside each watch is the Grand Seiko automatic mechanical Caliber 9S27, a movement that walks a fine line between thinness and performance, offering 50 hours of power reserve while delivering a mean daily rate of +8 to -3 seconds per day.

Grand Seiko STGK021 ladies automatic watch.

With the luxury of diamonds and the utility of a steel case and bracelet with a three-fold clasp, these three automatic watches are perfect for women in search of both practicality and elegance – of watches that are, and feel, special and yet are made to be worn often if not daily.

Grand Seiko STGK019 ladies watch with pink dial.STGK019
Grand Seiko STGK021 ladies watch with white dial.STGK021
Grand Seiko STGK023 ladies watch with blue dial.STGK023

STGK019 features a pale pink dial that calls to mind the color of cherry blossoms. STGK021 has a white dial with a pearl-like color. And STGK023 has a dial in a color referred to as “mizu-hanada,” a kind of indigo blue that has been lightened by dilution with water.

Grand Seiko STGK019 ladies watch with pink dial.STGK019
Grand Seiko STGK021 ladies watch with white dial.STGK021
Grand Seiko STGK023 ladies watch with blue dial.STGK023

These three watches will be available starting August 1 at Grand Seiko Boutiques and select retail partners.

Below, please find a gallery of live photos. Note that the watches featured here are non-functioning production samples.

Elegance Collection
Ladies Automatic STGK019
Elegance Collection
Ladies Automatic STGK021
Elegance Collection
Ladies Automatic STGK023

Is Spring Drive Antimagnetic?

Why is magnetism a problem for watches?

 

Magnetism has long been an issue in the field of watchmaking, and throughout the years different steps have been taken to deal with magnetic fields impacting performance, from the use of faraday cages to the development of alloys that can better resist magnetism’s effects.

On a fundamental level, several components in a standard mechanical movement can be susceptible to magnetism. Specifically, a magnetized hairspring will wreak havoc on a watch’s ability to keep accurate time. When a hairspring is magnetized, its coils stick together, which will impact the hairspring’s expansion and contraction ultimately reducing the movement’s amplitude. This will significantly effect a watch’s accuracy.

With Spring Drive, the engineers and watchmakers of the Shinshu Watch Studio offer a solution.

What is Spring Drive?

A breakdown overview of Spring Drive 9R86.
Spring Drive Chronograph Caliber 9R86. What is Spring Drive?

Spring Drive is a revolutionary movement and one of Grand Seiko’s defining horological markers. Just like a mechanical watch, Spring Drive utilizes torque generated by the unwinding of a mainspring. But in place of a traditional escapement there is the precision control system of an electronic watch that is regulating the accuracy through the use of an integrated circuit and crystal oscillator. Part of this mechanism is a rotor/glide wheel (not to be confused with an oscillating weight), which has a permanent magnet that, through magnetic induction, generates electricity to drive the IC and crystal oscillator, both of which in turn act as a check on the glide wheel by applying and releasing an electromagnetic break.

In short, magnetism itself is a critical component in the functionality of Spring Drive.

How does Spring Drive avoid the negative effects of magnetism?

Assembly of Grand Seiko Spring Drive caliber 9R65
Assembly of Grand Seiko Spring Drive caliber 9R65.

Through the use appropriate materials (brass, insulated copper) and adequate shielding, all Spring Drive models are magnetic resistant to 4,800 A/m, which is an ISO Standard adapted by and large across the industry.

Of course, Spring Drive’s biggest advantage over a standard mechanical watch is its lack of a traditional escapement, i.e., no hairspring. Without a hairspring to get magnetized, an owner of a Spring Drive timepiece should not have to worry about accidental exposure to a magnetic field magnetizing their movement.

One thing to note is that direct exposure to a strong magnetic field can temporarily lock the mechanism, but this will generally reverse itself after the magnetic source is removed and, in most instances, no further action is required.

What is Spring Drive – Automatic, Manual-Wind, or Quartz?

One of the most often asked questions regarding Spring Drive is whether it is automatic or quartz. This is almost certainly because, as an original movement technology, Spring Drive defies the simple categorization that most high-end watches fall into and with which most watch enthusiasts are acquainted. Spring Drive needs to be explained. That is what this article seeks to do.

Spring Drive prototype from 1982The very first Spring Drive prototype from 1982.
The second Spring Drive prototype from 1993.
Caliber 7R68, introduced in 1999 and the first Spring Drive caliber to be brought to market.Caliber 7R68, introduced in 1999 and the first Spring Drive caliber to be brought to market.

Spring Drive combines the most desirable elements of both mechanical and quartz watch movements while eschewing the greatest potential weaknesses of each. Because it has a mainspring, Spring Drive boasts a higher torque than that of quartz and is in this respect more in line with a mechanical movement. This allows Grand Seiko Spring Drive movements to power watches with larger and heavier hands, including those made of gold, as is the case with certain watches from the Micro Artist Studio. And because a spring, and not a battery, provides the power of Spring Drive, the movement can be powered up on demand without the need to replace and properly dispose of a battery.

A breakdown overview of Spring Drive 9R86.
Spring Drive Chronograph Caliber 9R86.

Unlike a mechanical watch, Spring Drive does not have an escapement, whether of the conventional lever type or any other variety. Instead, in Spring Drive, a mechanism called the Tri-Synchro Regulator replaces a delicate assembly of parts traditionally known for its thirst for oil and susceptibility to magnetism. We’ll explain how the Tri-Synchro Regulator works in a moment. But in a nutshell, it controls the flow of power as it is released by the mainspring while providing quartz-like accuracy of +/- 15 seconds per month (one second per day) in the case of the general 9R Spring Drive calibers and +/- 10 seconds per month (0.5 seconds per day) in the case of movements such as the 9RA2, 9RA5 and 9R01.

Grand Seiko Spring Drive 9RA2
Grand Seiko Spring Drive Caliber 9RA2.

Since the “mechanical side” of a Spring Drive movement includes a mainspring, Grand Seiko can offer 9R movements that wind up as diversely as mechanical movements do, which is to say there are both automatic and manual-wind variations of Spring Drive. What is more, the elaborate decoration, jeweling, and finishing that have long burnished the mechanical watch’s status as a lifetime product to be collected, appreciated, and passed down are also observed in a finely hand-assembled Spring Drive movement. There is much in common between these products.

But back to the Tri-Synchro Regulator, the thing that makes Spring Drive so singular and special. How does it do what it does? In the Tri-Synchro Regulator, a wheel at the end of the gear train called the glide wheel spins eight times per second and acts with a stator to generate power. As the glide wheel turns, it generates an electrical current, which activates a quartz oscillator and IC. The quartz oscillator’s vibration of 32,768 Hz provides a reference signal to the IC, which compares the highly accurate rate of quartz to the motion of the glide wheel, applying a magnetic break when it spins too fast, thus ensuring the hour, minute, and seconds hands move with the precision of a quartz watch.

Spring Drive 9R02.
Spring Drive Caliber 9R02.

If you look at a running Spring Drive watch movement, the absence of the flickering vibration of the escapement is apparent, just as holding it to the ear reveals a silence all its own. Nonetheless, the glide wheel can be seen spinning away, making its eight revolutions per second as the seconds hand on the dial flows effortlessly forward, reflecting the natural flow of time.

How Does Grand Seiko’s 9F Quartz Caliber Achieve its Accuracy?

 “What makes an ideal watch?”

Driving the engineers and watchmakers of the Shinshu Watch Studio, this question was answered with the introduction of Caliber 9F in 1993. Amazingly precise and designed to last, Grand Seiko’s 9F is the embodiment of an ideal, and not just regarding quartz timekeeping, but more broadly as to what a watch could and should be.

When Mr. Kuniharu Natori and his development team lead the charge on 9F, they sought to address three distinct areas: usability, legibility, and overall ease of maintenance.

To that end, Caliber 9F employs numerous groundbreaking innovations to achieve its high accuracy rate of ±10 seconds per year while also allowing Grand Seiko’s quartz watches to embody the brand’s exacting design aesthetic. These innovations include the Twin Pulse Control Motor, the Backlash Auto-Adjust Mechanism, a protective shield construction, and a regulation switch, among others.

Below, we explore the distinct features that allow Grand Seiko’s 9F calibers to achieve their exceptional accuracy.

In-House Quartz

The quartz crystals used by Grand Seiko are grown in-house in the company’s own autoclaves. This allows for tighter quality control, as each crystal is artificially aged in a controlled temperature and humidity, along with a controlled high voltage, for 90 days to ensure the stability of performance. It is then regulated by an IC in line with the specific performance characteristics of that crystal. Crystal oscillators are designed to oscillate 32,768 times per second, but that number is susceptible to temperature changes, and each crystal reacts to temperature fluctuations differently. This variation from one crystal to the next is accounted for by the individual movement’s IC.

Once cased inside the watch, the temperature sensor samples ambient temperature 540 times per day and, because quartz crystals are susceptible to temperature variation, uses that information to compensate by adjusting the frequency of the crystal. This bespoke approach is critical in ensuring the abovementioned precision of ±10 seconds per year.

Protective Shield Construction

Though quartz movements are less susceptible to outside forces, dust, and other contaminants can be introduced to the mechanism during battery changes, which can ultimately affect performance. To prevent this, 9F employs a protective shield construction that covers the gear train so that dust cannot enter the movement when the case back is open during service.

Magnetic Resistance

The 9F movement is protected from magnetic interference via a combination of a unique motor design (with magnetic conductors) and an anti-magnetic iron plate. This provides anti-magnetic resistance of up to 4,800 A/m (60 G), which is the same level of protection stipulated by the ISO standard for diver’s watches.

Regulation Switch

All 9F movements come equipped with a regulation switch. This ability to regulate is a common feature of mechanical movements, though it is almost never seen in any quartz counterparts. With this, one can perform a fine adjustment should the need ever arise.

Backlash Auto-Adjust Mechanism

There is always a small amount of backlash between teeth along a gear train as they engage with each other, which translates to a seconds hand that appears to shudder as it advances around the dial. The watchmakers working on 9F determined that precision on the dial side of the watch is equally important – it is, after all, the interface of the watch – and to that end, they devised the Backlash Auto-Adjust Mechanism. It is essentially a small gear equipped with a hairspring placed along the gear train, and it works by exerting the torque of the coiled hairspring back to the gear train, minimizing the play between teeth and mitigating any considerable shake.

The introduction of 9F is evidence that Grand Seiko takes quartz watches seriously. So much so, in fact, that each movement is hand-assembled by a highly skilled Grand Seiko watchmaker.

Grand Seiko Watches & Wonders 2023 Digital Product Presentation

Please enjoy this presentation from Seiko Watch Corporation President Akio Naito as he walks us through Grand Seiko’s Watches & Wonders 2023 novelties and gives us a closer look at Grand Seiko’s watchmaking studios.

What is Grand Seiko’s Ever-Brilliant Steel?

As a vertically integrated manufacturer, Grand Seiko consistently pushes the envelope in all facets of watchmaking. Innovation has always been a fundamental part of the brand, informing groundbreaking leaps in all facets of horology, from the development of new movements to techniques in finishing, and more. The goal, of course, hasn’t changed since before the days that led to the first Grand Seiko timepiece in 1960: to produce the “ideal watch,” with a focus on precision, legibility, beauty, and durability.

Grand Seiko’s approach to metallurgy, or the science and technology of metals, has played an important role in executing these brand values. Using different materials, Grand Seiko has been and continues to be a pioneer in the field of metals, encompassing all parts of the watch.

At Watches & Wonders 2023, Grand Seiko unveiled five new references featuring cases made of Ever-Brilliant Steel, a special alloy making its way into the brand’s catalog. Today, we’ll take a closer look at this novel case and bracelet material and how it compares to the industry standard.

Stainless Steel

Zaratsu polishing a stainless steel case.
Zaratsu polishing a stainless steel case.

Most Grand Seiko watches today are made of stainless steel using an alloy that is generally considered standard across the high-end watch industry. With its high hardness, low carbon content, and antimagnetic properties, stainless steel is an excellent option for use in cases and bracelets. Additionally, it has notable anti-corrosive properties, which means it is an incredibly hard-wearing metal that can theoretically stand the test of time against pitting.

To make the most of the beauty of this metal, Grand Seiko applies a finishing known as Zaratsu. Named after the phonetic pronunciation of an old European machine called Sallaz, Zaratsu polishing is applied to all Grand Seiko cases, and it is instrumental in creating and defining the distinct Grand Seiko aesthetic defined by flat surfaces, sharp edges, and a distortion-free mirror finish. In short, Grand Seiko’s defining look is made possible through this markedly Japanese finishing technique.

Ever-Brilliant Steel: the world’s most corrosion-resistant stainless steel

A special alloy used in a handful of new Grand Seiko references, Ever-Brilliant Steel marks a notable leap in the brand’s pursuit of perfection. As one of the most corrosion-resistant stainless steel alloys, Ever-Brilliant Steel has a PREN (Pitting Resistance Equivalent Number) rating that is 1.7 times higher than that of stainless steel. With durability being one of Grand Seiko’s fundamental values, the development and use of this material further reassures the watch’s lasting beauty.

Grand Seiko Hi-Beat GMT SBGJ263 watch.
Grand Seiko Hi-Beat GMT SBGJ265 watch.

As the name suggests, Ever-Brilliant Steel has a brilliant white hue. When compared to Grand Seiko watches using standard stainless steel, watches made of Ever-Brilliant Steel will appear whiter along the hairline finished portions, giving the cases an immediately eye-catching appearance. Grand Seiko also Zaratsu polishes Ever-Brilliant steel, which is notably more difficult to finish to the brand’s exacting standards.

Currently, Ever-Brilliant steel is used across six regular production models in Grand Seiko’s collection. All feature Grand Seiko’s modern interpretation of the 44GS design, which is an excellent showcase for the intrinsic beauty of this alloy, made even more impressive through the high level of execution across the mirror-polished and hairline-finished surfaces.

Heritage Collection
Hi-Beat 36000 SBGH299
Heritage Collection
Hi-Beat 36000 SBGH301
Heritage Collection
Hi-Beat 36000 GMT SBGJ263
Heritage Collection
Hi-Beat 36000 GMT SBGJ265
Heritage Collection
Hi-Beat 36000 GMT SBGJ267
Heritage Collection
Hi-Beat 36000 80 Hours SLGH013