Grand Seiko Ushio Tide Spring Drive SLGA015 Watch Review
The Grand Seiko Ushio Tide Spring Drive SLGA015, unveiled at Watches & Wonders 2022, redefines the utilitarian divers’ watch courtesy of its strongly patterned black dial, exquisitely polished case and supremely precise Spring Drive movement. Mark McArthur-Christie points out why Grand Seiko has a tendency to be, well, ‘a bit obsessive’, before going on to share his opinion on this fascinating subaquatic timepiece.
Grand Seiko – a bit obsessive
It’s probably fair – and a compliment – to describe Seiko as ‘a bit obsessive’. Where other watchmakers may buy in a dial here, a set of hands there, a case from somewhere else, Seiko will do it all by itself. It will do it to a remarkably high standard, too. Even a basic Seiko will have a finish and a quality that a lot of other makers charging a great deal more would envy. And then there’s Grand Seiko. If Seiko is ‘a bit obsessive’, GS is the sort of place where each sugar crystal in the bowls on the staff canteen tables is hand-polished.
Grand Seiko Shinshu Watch Studio
It’s not just persnicketiness for persnicketiness’ sake, though. The Grand Seiko Shinshu Watch Studio alone needs an extension for the watchmaking awards they’ve won. The Mens’ Watch Prize at the 2021 Grand Prix d’Horlogerie de Genève (GPHG) went to its Hi-Beat 36000 80 Hours cal. 9SA5. However, the brand’s talents are not just limited to making mechanical movements fitted with the brand’s dual impulse escapement. On the contrary, they extend to their unique Spring Drive calibres, just like the one you’ll find in the Grand Seiko Evolution 9 SLGA015.
Spring Drive – Yoshikazu Akahane
It’s fair to say that this attention to detail means Seiko doesn’t go rushing into things. There’s no way the watchmaker will send anything out into the world that isn’t as damn near perfect as it can be. It took more than 20 years from Yoshikazu Akahane’s original idea for the Spring Drive movement to turn into the first Japan-only production model in 1999. Since then, the movement has been through four manual-winding calibres and 19 automatic variations before the current two movements saw the light of day.
Spring Drive glidewheel
There’s been plenty written about the Spring Drive movement, so suffice to say it’s a mechanical/quartz hybrid that combines the best of both methods of timekeeping. You get the ‘soul’ of a mechanical watch, with its going train (minus balance and escapement) but the accuracy and reliability of quartz. The escapement and balance get replaced with a ‘glidewheel’ that powers the watch’s second hand and is regulated with an electromagnetic brake. You can spot a Spring Drive by the way the second hand doesn’t tick or even stutter round the dial in tiny steps – it simply glides. The nearest comparison would be the way an old tuning fork Accutron movement’s second hand looks when it’s running.
Calibre 9RA5
In this case, the Grand Seiko Ushio Tide Spring Drive SLGA015 is powered by the 38 jewel Spring Drive 5 Days cal. 9RA5, a self-winding movement. Once fully powered, there’s a significant 5 days of reserve to keep you going. Accuracy-wise, as you’d expect, the Spring Drive movement is precise with a variance of just 0.5 secs/day. It’s a good-looking movement, too. There’s perlage on the plate as well as anglage, heat-blued screws and the Grand Seiko name picked out in blue.
ISO 6425 standards
Just take a look at that dial presented in black. Divers are supposed to be all about boring old utility, right? Not in this case. Grand Seiko tells us that the texture on the dial is supposed to reflect the “…dynamic and sometimes violent tides caused by the Black Stream…” This is the Kuroshio Current that runs northwards towards the North Pacific past Japan. It’s one of the largest ocean streams in the world. No matter where Seiko got the idea, it’s a cracker. The dial is just as readable as a plain black face (it still hits ISO 6425 standards for dive watches) and it looks gorgeous too.
Luminescent hands
The brushed hour and minute hands stand out against it clearly (so does the polished second hand with its lumed lollipop base). That hour pointer is almost a cathedral hand with its three segments of lume. The minute hand is a classic Seiko diver-flared arrow end and again plenty of lume. All in all, it’s a standout dial in terms of legibility and clarity as well as interest. The applied markers make it a snap to read at a quick glance.
High-Intensity Titanium
Seiko is making the cases for this particular range of watches from what they’re calling ‘High-Intensity Titanium’. After a bit of digging, it looks as though rather than a case finishing process, this refers to the composition of the metal alloy itself; titanium, iron and niobium. The watchmaker also says this alloy is more scratch-resistant than stainless steel with a Vickers hardness rating of 250-350 (stainless usually comes in around 150-250). It’s perhaps fortunate that they decided to go with titanium rather than 316L as it’s a chunky old case at nearly 44mm diameter and around 14mm thick. There’s a substantial weight saving there – the metal they’ve used is around 30% lighter than stainless.
Grand Seiko Ushio Tide Spring Drive SLGA015 – case finishing
The case finishing is, as you’d expect from Grand Seiko, straight from the top drawer. There’s the usual mix of brushing on the main case and polishing on the facets that join the case sides to the top. The bezel has a ceramic infill and is one of the clearest and smartest I’ve seen on a diver in a while with its arrow markers under each numeral. Seiko has left the very edge of the ceramic uncoated to let the texture show through next to the knurled edge of the metal bezel side.
Practically, the crown screws in on a smooth, positive thread and is protected by a couple of chunky guards that flare out from the case sides. The caseback screws in too and Seiko is happy to say that the whole plot will keep water out to 200m – way past the practical depth pretty much anyone needs unless they earn their living sitting in a saturation diving chamber. The crystal is sapphire and anti-reflective coated.
Grand Seiko SLGA015 v Rolex Submariner
It’s all held on with a light titanium bracelet, secured with an adjustable three-fold clasp and push button release.
One could probably debate the whole ‘is this a Sub-killer?’ question for hours over a whisky or two. But that would rather miss the point. The SLGA015 is a tad more expensive at £9,970 than the Sub, but it’s sufficiently different in terms of movement, metal and design to be a colleague rather than a competitor.
Further reading
https://www.grandseikoboutique.uk/
Technical specifications
- Model: Grand Seiko Ushio Tide Spring Drive SLGA015
- Case: high-intensity titanium case; diameter 43.8mm; height 13.8mm; water resistance 20ATM (200 metres); sapphire crystal to front; screw caseback.
- Functions: hours; minutes; central seconds; date; power-reserve indicator
- Movement: Spring Drive 9RA5; Self-winding movement; 38 jewels; power reserve 120 hours.
- Strap: high-intensity titanium bracelet with a 3-fold clasp with push button release, secure lock and extender.
- Price: £9,970 – (RRP as of 25.7.2022)