Baselworld 2011 In Review: Gronefeld One Hertz

Gronefeld One Hertz

Across from the Academie Createur Hologerie Independent booth is a small pseudo-shop with the title “Independent Watchmakers”, inside, amongst a few other well-known small brands are the brother’s Tim and Bart Gronefeld.

The brother’s are two of the most talented makers of Tourbillion movements at work today, but in addition to this they have also been working on watches to their own design and after a somewhat difficult last couple of months they are ready to show off their second movement, the GS-02.

Let’s be frank the view through the sapphire back is fantastic, except for one small bridge in the center, the rest are all mounted peripherally providing glimpses of the components hidden beneath. But it is not the components themselves that make this watch special it is the way they have been put together; this watch has a deadbeat second.

Unlike the more common sweep seconds which uses multiple, high frequency ticks to produce a more or less smooth progression, the deadbeat second moves just once per second with a definite “tick”. This complication, prior to the advent of the quartz watch, was common, but it subsequently became associated with the cheap quartz watch and disappeared.

Gronefeld One Hertz

The Gronefeld brothers have taken the dead beat second one stage further and given it a separate barrel and power train independent of the main barrel which is now used only for the hours and minutes. The aim by separating the two mechanisms is to reduce any interference to the main balance and escapement.

Another interesting, though perhaps not so unusual, design function is that the hands are set by pushing the crown rather than trying to break a fingernail or scratch the case trying to pull it out. To make it clear which function is active the dial has an indicator (S)et or (W)ind at the 3 o’clock position, it’s a nice touch.

Elsewhere on the front, the dead beat seconds is the dominant feature, this is no tiny little seconds hand, it takes up over half the surface area of the dial and emphasizes the strong steady “tick” of the movement. That strength is reinforced by the actual tick of the movement, it has a definite “clunk” and is surprising even when you are expecting it. It is just so different from all other modern watches.

There are two different versions, stainless steel with a gray color scheme, and a rose gold case with their “Dune” colors which equates to browns and golds. Both are extremely classy, but personally I would go for the stainless steel. Quantities are limited, 12 stainless steel and 20 in Rose Gold

Gronefeld One Hertz

The Final Word
Any independent watch-making project is not without challenges; technical, financial and physical. It takes a special dedication to create anything let alone something as extraordinary as the Gronefeld One Hertz. The brothers should be proud of what they have achieved and hopefully this will be a springboard to even greater heights in the future.

For more information please visit or check out their active Facebook page.

Ian  Ellery
Ian Ellery is a guest contributor on The Watch Lounge. When he’s not writing about watches he presents his technology radio show in Geneva, collects vintage watches and attends auctions.

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