Grönefeld One Hertz Dune
The name of the Grönefeld One Hertz does not refer to the frequency of the balance. On the contrary, the nomen of this watch indicates that it is endowed with a ‘seconde morte’ or ‘deadbeat seconds’.
I’m a hopeless cook. If I open a tin of baked beans and place them in a pan, it is inevitable they will become a congealed mass within two nanoseconds. I don’t know why I am hapless with food preparation, my substantial waistline would lead the casual observer to assume I am a culinary genius.
My domain is writing about watches and I readily employ horological terms as a matter of routine. It does not endear me to those Philistines who fail to appreciate the emotional appeal of Haute Horologerie, but I don’t care. My life is dominated by a compunction to wax-lyrical about finissage, complications, enamelling and such matters.
One Hertz
I often look at the specifications of wristwatches and record details of movements such as the number of parts, jewels, power reserve and frequencies. Indeed, it is the frequencies of 2.5Hz, 3Hz, 4Hz, etc that I typically note. There are some watches which have higher frequencies but these are few and far between.
My incredulity was heightened when I saw a press release for the Grönefeld One Hertz Dune. The slow cadence of the watch appeared to fly in the face of the dizzyingly fast frequencies beloved by some brands. However, all was not as it first appeared.
The two Dutch brothers, Tim and Bart Grönefeld fooled me into thinking the ‘One Hertz’ nomen, referred to the frequency of the balance wheel. It actually refers to the deadbeat seconds, sometimes referred to as “seconde morte” or “jumping seconds”. The second hand moves in one second increments, hence the name. The motion of the seconds hand resembles the advancing hand of a quartz watch. But, this is no quartz watch but a mechanical timepiece created in an atelier in The Netherlands by a small team of artisans.
Dead beat seconds
The complication of a dead beat seconds may not sound remarkable to those naive about horological matters. Yet, this complication is incredibly complex, necessitating immense skill and ingenuity. The seconds hand on the Grönefeld One Hertz Dune remains stationary until a full second has elapsed and then it jumps to the next integer on the chapter ring. This model features two spring barrels, one to power the hours and minute hands, whilst the other spring barrel drives the independent deadbeat seconds.
In some watches equipped with a deadbeat seconds complication, the tension, which accrues prior to the second hand jumping to the next integer, can create ‘turbulence’ according to Bart. However, the One Hertz”, thanks to the twin spring barrels, two gear trains and three-armed anchor, the complication does not impair the chronometric precision of the timepiece.
Grönefeld One Hertz – dial
The Grönefeld One Hertz Dune is presented with a chestnut dial, contrasting charmingly with 18-carat 5N rose gold.
An off-centre hour and minute display is located at 1 o’clock. It has a snailed centre, framed with a black chapter ring. Applied, metalized, triangular-shaped batons indicate the hours. Dauphine-style hands, presented in a golden hue, convey the hours and minutes.
A larger dial spans the aforementioned hour and minute display. It is constructed of sapphire with metalized indices against a black chapter ring. It is mounted to the main dial utilising four screws. The snailing is repeated, save for the area occupied by the power-reserve indicator.
Image – Grönefeld One Hertz 1912
The power reserve is presented on a smooth area using a crescent-shaped scale and a slim gold-coloured hand indicates the energy stored within the twin barrels. Adjacent to the crown, the design code of the power reserve is repeated. This time a hand shows ‘S’ and ‘W’. The text refers to ‘Setting’ and ‘Winding’. By simply pushing the crown, the wearer can switch between setting and winding.
Two cartouches feature at 4 o’clock and 10 o’clock. They are engraved, ‘One Hertz’ and ‘Grönefeld’ respectively.
Image – Grönefeld One Hertz Ruthenium
Grönefeld One Hertz – case
The 43mm case diameter will appeal to the majority of potential wearers. The upper surface of the bezel and lugs is highly polished while the caseband is satin brushed, with fine, straight graining, deftly applied by hand.
The caseback is fitted with a sapphire crystal, indulging the wearer with a view of the exceptional hand-finished movement. Gold screws secure the caseback in position. The slots are flawless and a testament to the perfectionism practised by the Grönefeld team.
Caliber G-02
I have already discussed the complexity of the dead-beat complication on this watch, but there are many additional aspects which distinguish this timepiece as a paragon of craftsmanship. The movement comprises 285 parts all beautifully presented. The Caliber G-02 has 39 jewels, each one mounted in a gold chaton.
Image – Grönefeld One Hertz Platinum
At first glance, the movement appears modern, courtesy of the avant-garde micro-blasted treatment adorning the bridges. However, close examination reveals hand-bevelled edges to the stainless steel bridges. Moreover, they are spotted underneath and presented with circular graining on their upper surfaces
The brand name and number of jewels are relief engraved on the bridges. Nothing ever appears to be conceived for expedience or to make the brother’s lives easier. In theory, a deadbeat seconds should consume more energy than a regular timepiece, but this watch has twin barrels. This results in an impressive 72-hour power reserve.
Conclusion
If you study the watches crafted by the Horological Brothers, Tim and Bart Grönefeld, it soon becomes apparent that they are the antithesis of mass production. Their relentless obsession with detail is very tangible as you study the numerous examples of flawless finishing and elevated engineering. Therefore, it should come as no surprise to learn that Grönefeld only produces a limited number of watches. It would be difficult to imagine how they could make these watches, embracing less labour-intensive methods, without sacrificing their cherished high standards of work.
Image – Grönefeld One Hertz Platinum
I would dearly love to own a Grönefeld timepiece, but sadly the most accessible model, presented in stainless steel is now sold out. The watches represent value compared to many offerings from mainstream brands, yet proffer exclusivity. Moreover, they indulge the needs of those individuals seeking no-compromise creativity. I dream of the day when I can order a Grönefeld One Hertz Dune and enjoy the product of this talented double act.
Technical specification
- Model: Grönefeld One Hertz Dune
- Case: 18-carat 5N rose gold case, diameter 43.00 mm, height 12.50 mm, water resistant to 3 bar (30 metres), sapphire crystal to the front and caseback.
- Functions: Hours, minutes, dead-beat seconds, power-reserve, setting-winding indicator.
- Movement: Calibre G-02, Hand-wound movement, frequency 21,600 vph (3 Hz), 39 jewels, power reserve 72 hours, 285 parts.
- Strap: Black alligator leather strap with 18-carat 5N rose gold pin buckle.
- Limited Edition: 20 pieces