The Daniel Roth 8-Day Tourbillon, Ref. 197

An overview of its conception and assembly process


By Alberto Schileo and Curtis D. Thomson
© April 2004 by the authors and ThePuristS.com

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Daniel Roth stock photo

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Part 1: Introduction

Few things require as much technical mastery and craftmanshp as making, finishing and assembling a tourbillon. However, if one were to ask you today which companies currently pride themselves in producing their own “manufactured” tourbillon calibers (i.e. not made by some other company owned by the same group), chances are that you would not immediately think of Daniel Roth. Yet, you would be wrong not to do so: not only do they have their own 100% in-house tourbillon movement, but in fact they make several different ones!

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Daniel Roth stock photo

Last August, Curtis D. Thomson, ThePuristS resident watchmaker, and myself were priviledged to stay for a few days in Le Sentier, spending time with the Daniel Roth staff while going over the entire manufacturing process of their new 8-Day Tourbillon watch. We are grateful to Mr. Gérald Roden, Chief Executive Officer of Daniel Roth and Gérald Genta, to the head of Manufacturing, and to all the rest of the Daniel Roth staff for having opened their offices to us, and for having taken the time to share their work, and obvious passion, with all PuristS.

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Mr. Gérald Roden
Daniel Roth stock photo

The driving force behind Daniel Roth’s decision to develop their own in-house tourbillon caliber was two-fold. First, there was Lemania’s decision to stop delivering ebauches outside of the Swatch Group: as Daniel Roth tourbillons had always been based on Lemania calibers, this was an obvious problem! However, at the same time, there was also the desire by Daniel Roth to underscore to the world the fact that they are a “manufacture horlogère” in the true sense of the word.

This is why they set out from the start to make an 8-day, manual wind tourbillon (Daniel Roth caliber 720), which no other brand was offering at the time. A few things were clear from the beginning: in keeping with the “tradition” of Daniel Roth tourbillons, the watch would be “double-face”, and it would continue to use the three-pronged seconds hand which has become so emblematic of the brand.

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Daniel Roth stock photo

 

Part 1: Design

Designing this new watch from scratch did not prove to be easy, as the candid and open discussion we had with the head of the Daniel Roth Design Office, revealed.

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Daniel Roth stock photo

First, the case. The flip-over design was one of Daniel Roth’s (the man) original ideas, which he was however not able to implement as he was never quite satisfied with the way it worked. Making this case proved indeed challanging, as no drawings from the original idea/case remained, and the whole concept had to be redeveloped from scratch (click here if you wish to see a picture of the original, flipping Daniel Roth tourbillon watch case). In the end, the back of the case had to be made of solid gold, as opposed to being open as in Daniel Roth’s original design, to circumvent the rigidity problems which he had faced.

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Second, the double barrels. The very first prototype they assembled had the pinions and wheel teeth break halfway through being wound up, because there was so much torque being applied to them! So, in the end, they had to add a set of wheels acting as a differential to reduce the gear ratio: this made it longer to fully wind up the watch, but as this is usually done only once a week this solution ended up being acceptable.

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Third, the power reserve. Towards the end of the design process, Mr. Roden decided to change the power reserve indicator from a hand to a window. However, as they had already made a lot of the parts necessary for the movement, they had to change this in a way to be able to reuse as many of the original parts as possible. Once they did this, it became apparent that the chapter for the date had become too small compared to the rest of the indications on the back of the watch! So they ended up having to shift the date circle down as much as the wheels - which had also already been made - allowed for.

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Fourth, the cage. Ever since the Daniel Roth and Gérald Genta brands were united by the Hour Glass, and the fully integrated by Bulgari, they have been sharing resources in terms of product development and manufacturing. It won’t come as a surprise, then, to learn that the design of the new tourbillon cage actually came from a Gérald Genta caliber, though this had to be flipped upside-down (as in all Gérald Genta watches the tourbillon was visible through the back of the watch, and not the front).

In fact, the first prototype which was ever made of the new Roth 8-day tourbillon caliber actually used a cage straight from a Gérald Genta tourbillon; this movement ran for over a year, and was used as a proof of concept to make sure that they were indeed getting 8 days of power reserve, etc. (interestingly enough, as they had used a non-modified Gérald Genta cage, this tourbillon actually turned backwards!).

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Fifth, the tourbillon bridge. Originally, at Daniel Roth they had considered adopting the same concept as the first Roth tourbillon (i.e. a bridge), but then they decided to replace this with a plate, which would lend itself to being decorated in different ways (“côtes de Genève”, engraving, precious stones, etc.). In our Basel 2003 report, we already showed you pictures of a diamond-studded Daniel Roth tourbillon watch, with the bridges covered by precious stones (click here if you want to see a picture).

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Daniel Roth stock photo

Sixth, the dial. In designing the new dial, the general consensus at Daniel Roth had been that the old one had the hours/minutes chapter which was too small and the seconds chapter which was too big (boy, do I personally not agree with this!!! ). So the new dial design uses a larger hour chapter, a longer hour hand, and narrower scales for the three 20-second segments (effectively “compressing” these together compared to the original tourbillon). The two circles described by the hours and seconds chapters, however, are now of the same size.

As the design work for this tourbillon caliber was underway, at Daniel Roth it was decided to also develop a second tourbillon caliber, which this time would be smaller, thus allowing it to be mounted in L and X cases through different mounting rings. This one is coming out in two different versions: one with a retrograde date indicator, as Mr. Roden himself has already hinted at in our own forum (click here to read his message), and a future one, which will have… well, I guess you’ll have to be patient for that one, which will associate two elements which in my opinion perfectly exemplify Daniel Roth watches!

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Daniel Roth stock photo

When we visited the manufacture, they were in the process of designing this new tourbillon caliber, so the CAD drawings we saw, as well as the parts which were being made in the workshops, belonged to this new caliber. All parts for the 8-Day Tourbillon had in fact already been made by then, and were at the time already in the assembly stages.

Speaking of which, I am pretty sure that by now you are getting curious as to how the whole process took place, so I will attempt to describe as much as possible of it here, step by step.

Continue to Part 2: Manufacturing


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Copyright April 2004 - Alberto Schileo, Curtis D. Thomson and ThePuristS.com - All rights reserved