A Light In The Darkness: De Bethune Launches The DB28GS Swordfish

The problem of how to illuminate a watch dial is almost as old as horology itself. Back in the mid-17th century, the Campani brothers developed the wandering hours clock in which the wandering hours sector was backlit by an oil lamp. In the early 20th century, radium paint became popular but the hazards attendant upon using it made the industry switch to the less dangerous tritium. Tritium has an unfortunately short half life and is still a radiation hazard, so eventually everyone switched over to using a light-charged luminous pigment developed by the Nemoto Corporation in Japan, which is now manufactured under license in Switzerland by Tritec AG, where it’s known the world over as Super-LumiNova.

SLN has the unfortunate disadvantage of glowing brightly at first but fading over time and so the quest for a better solution continues. Taking a cue from the on-demand chiming of the time in minute repeaters, De Bethune in 2019 debuted the DB28GS (Grand Sport) Grand Bleu. The DB28GS Grand Bleu is a fully ISO 6425 compliant dive watch, although it’s about as different from the copy-paste family resemblance most dive watches have with each other and with the ur-dive watch designs from the mid-1950s. The Grand Bleu has DB’s signature delta bridge for the two staggered mainspring barrels, a full suite of De Bethune horological innovations in the oscillator assembly and antishock system, and most especially, it has an internal, pusher-activated electrical generator, which can be used to illuminate the dial long after any SLN will have faded into wraith-like invisibility.

This year, De Bethune is introducing the DB28GS Swordfish, the latest version of the DB28GS and the latest De Bethune watch to feature the internal, mainspring powered dynamo system introduced in the DB28GS Grand Bleu in 2019 and then a year later, in the DB28GS Yellow Submarine, with its heat-tempered titanium case brought up to a golden yellow (an unusual heat temper in watchmaking in general, and I think unheard of outside De Bethune in titanium).

The Swordfish, like its predecessors, has a five day power reserve and the internal generator is activated by pressing a pusher located at 6:00 and integrated into the case by an ovoid housing. The pusher, when held down, begins to draw torque from the left mainspring barrel and as long as the pusher is held down, the diodes will continue to cast light on the dial.

The DB28GS Swordfish has a five day power reserve. In order to prevent the dynamo from inadvertently running down and stopping the watch, the Swordfish like its predecessors is designed so that the dynamo won’t function if there is one day or less left in the power reserve. The power reserve indicator is located on the dial side of the watch; the sector is visible between 9 and 10:00.

The Swordfish, as we’ve mentioned, is fully ISO 6425 compliant, with a 105 meter water resistant case, a unidirectional timing bezel, and luminous material on the hands and dial. There are also all of De Bethune’s patented horological inventions, including a blued titanium balance with white gold rim weights, De Bethune’s flat balance spring with self-centering, terminal curve affix (this essentially gives you all the advantages of a Breguet/Phillips overcoil without the added height) and the Triple Pare-Chute antishock system, in which the upper balance pivot is under a balance bridge with two additional antishock assemblies at the end of each arm.

The case of the DB28GS Grand Bleu is in titanium; the Swordfish has a case made of zirconium, with the surface heat treated to produce a surface layer of zirconium oxide, the essential ingredient in most ceramic watch cases. The surface treatment makes for a hard, scratch-resistant exterior which is also essentially impervious to corrosion (I get nervous every time I write that because there are some mighty corrosive reagents out there, including chlorine triflouride, which will react enthusiastically with things that you’d think wouldn’t react with anything, like asbestos, reinforced concrete and “test engineers” but unless you are planning on taking a nosedive into hypergolic rocket fuel, zirconium oxide is probably a pretty safe bet).

Because the mainspring barrel drives the dynamo, a regulator is required to control the rate at which the barrel unwinds, and the DB28GS Swordfish has a minute repeater style centrifugal regulator, visible on the dial at 3:00.

The DB28GS Swordfish is available at launch at $120,o00.

The De Bethune DB28GS Swordfish: case, black zirconium, black brushed and polished stainless steel caseback and bezel, 44mm x 12.8mm with floating lugs, 105M water resistant. Movement, caliber DB2090, 30mm diameter, 5 day power reserve with De Bethune balance spring, silicon escape wheel, Triple pare-chute antishock system and LED dynamo powered dial lighting system, running at 28,800 vph in 51 jewels. Delivered with canvas and rubber straps. Price, $120,000.

The 1916 Company is proud to partner with De Bethune and Denis Flageollet. Contact us for availability.