Precision & Craftsmanship Collide In Grand Seiko’s Tentagraph, Their First-Ever Mechanical Chronograph

The following article was produced in partnership with Grand Seiko.

Grand Seiko never does things by halves – so it stands to reason that when they revealed their first-ever mechanical chronograph, the SLGC001 Tentagraph, at Watches & Wonders Geneva earlier this year, the watch fraternity knew that it was going to be rather special.

In short, we weren’t disappointed. The Grand Seiko Tentagraph, the new flagbearer for Grand Seiko’s Evolution 9 Collection, is a major milestone in the history of Grand Seiko as well as a luxury sports chronograph non pareil.

WATCH a close-up look at the Grand Seiko Tentagraph below.

First of all, we should explain the name ‘Tentagraph’. It’s a compound word that refers to how the Tentagraph’s movement beats with a frequency of ten beats per second, boasts a hefty three-day (72-hour) power reserve, and that it’s an automatic chronograph. If that doesn’t already impress on you how, well, impressive the Tentagraph is, let us explain further.

Beating at ten times per second ensures that the new Tentagraph Calibre 9SC5 maintains high accuracy when measuring elapsed time as well as the time of day. For a sports instrument like a chronograph, accuracy is of the utmost importance – but that accuracy cannot compromise the essential time-telling function of the watch, which is why a high-frequency movement is so valuable.

Grand Seiko’s dedication to accuracy with the Tentagraph is unparalleled. As with all Grand Seiko mechanical movements, the Tentagraph’s time-of-day accuracy is assessed in six positions and at three temperatures over 17 days but, in addition, the Tentagraph has gone through a longer and more brutal testing assessment that features three more days of testing, during which the accuracy is assessed in three positions while the chronograph is in operation.

Thus, in total, each Tentagraph movement is tested for 20 days to ensure that it meets the Grand Seiko Standard of +5 to -3 seconds per day. For the record, that’s a more stringent testing process and accuracy standard than Switzerland’s COSC, which should tell you everything you need to know…

However, the really cool feature of the Calibre 9SC5 is how, thanks to its energy-efficient escapement and two barrels, the watch can run for three days even when the chronograph is in operation. That makes the Tentagraph the 10-beat chronograph with the longest power reserve in the industry today, according to Grand Seiko.

72 hours is a very decent power reserve for any mechanical watch, but 72 hours whilst the chronograph is still running? That’s unheard of, and testament to Grand Seiko’s watchmaking prowess.

The Tentagraph isn’t just technically impressive, though: it’s a knock-out when it comes to looks, too. Sporty and classy in equal measure, with a distinctly Japanese and distinctly Grand Seiko aesthetic, the Tentagraph is beautiful inside and out.

Crafted from high-intensity titanium, which is about 30% lighter and more scratch resistant than stainless steel to maximize durability, the Tentagraph’s case is subtly curved, which makes it sit more comfortably on the wrist while providing a unique form factor that’s visually intriguing. Wide lugs and beautifully machined concave chrono pushers add to its beauty as well as its ergonomics.

The finishing of the Tentagraph’s case features alternating Zaratsu-polished, distortion-free mirror finishes and delicate hairline finishes, giving the case the harmonious glow characteristic of Grand Seiko’s new Evolution 9 Style. Grand Seiko’s case finishing is utterly meticulous and the Tentagraph is a masterclass in finishing metal. The Zaratsu polishing on the Tentagraph is something that you’ve truly got to see to understand in particular – it’s mesmerising.

Another hallmark of Grand Seiko is their impressive dials – and the Tentagraph’s is another killer example of what they’re capable of. It features Grand Seiko’s signature “Mt. Iwate pattern,” which takes inspiration from the ridged contours of the eponymous mountain, which is visible through the windows of the Grand Seiko Studio Shizukuishi, where the Tentagraph and all other Grand Seiko mechanical watches are hand-assembled and adjusted.

The dark blue, subtly textured dial is complemented by even darker blue snailed chrono subdials, arranged in a classic tri-compax pattern, and a black ceramic tachymeter bezel, which protects the watch from scratches as well as facilitates the chronograph’s function. Generous smatterings of lume and finely-polished indices provide a tasteful contrast to the Tentagraph’s otherwise dark colour scheme.

The best bit? The Tentagraph has an exhibition caseback, through which you can admire the beautifully finished Calibre 9SC5, and watch its vertical clutch and column wheel spring into action as the chronograph is activated. Can you tell that we love this watch?

The Grand Seiko Tentagraph isn’t just the perfect expression of an Evolution 9 sports watch, but it’s also the perfect expression of Grand Seiko’s uncompromising approach to mechanical watchmaking.

Technically extraordinary, masculine, sporty yet elegant and exceptionally Japanese (in the best way possible), the Tentagraph charts a new course for luxury sports watches. It’s a very exciting thing indeed.

Find out more about the Grand Seiko Tentagraph at Grand Seiko’s online boutique here.