At BaselWorld 2018 NOMOS launched a new movement: caliber DUW6101. It boasts an array of clever solutions to age old problems, and we felt it deserved a thorough explanation that goes beyond a few bylines in an article on the watches that are powered by it. Luckily Rob Nudds, our representative at NOMOS, happens to be both a gifted watchmaker as well as a talented writer. Below is his take on this exceptional movement.
The NOMOS DUW6101 is a revolution for the independent German watchmaker. Based on the principles of the slim-line DUW3001 released in 2015, the new movement features a quick-change date complication with a unique safety mechanism designed to protect the movement from damage.
Normally, it is not advisable to change the date of a quick-change calibre when the hands are positioned between 10pm and 2am. There is a little variation in these parameters from movement to movement, but the principle remains the same – during this ‘danger zone’ the date change wheel is in contact with the date wheel teeth, ready to flick the date over to the next day when the hands hit 12 o’clock. Attempting to change the date while these components are engaged can strip the teeth from the date wheel, resulting in a necessary service.
As a small, owner-operated company, NOMOS Glashütte was keen to develop a mechanism to prevent this – another example of their endeavour to improve the quality and durability of their output across the range. Resilient mechanisms make sense for the brand, their dedicated retailer network, and the end-consumer: A safe and secure mechanism results in less after sales concerns, more time for the retailers to focus on selling, and greater peace of mind for the customer. To this end, NOMOS spent four years developing this new function. The final product is a perfect of example of the NOMOS philosophy: To find a simple solution to a complex problem, and to focus on its execution rather than embellishment, through excellent design and top-quality manufacturing.
Instead of the traditional set-up, the DUW6101 uses completely new components. A double-level wheel, mounted with a specially formed date-change hammer and cam is responsible for moving the date from one day to the next during normal operation. On the other side of the movement another double-level wheel engages with the date wheel teeth when the watch is in date set mode. This wheel features a five-fingered star wheel on top to move the date wheel quickly, and a lower level wheel that engages with the setting mechanism itself. The tension between these two levels is crucial. Together, they act as a ‘slipping clutch’ when the hammer is resting on the date wheel teeth between 11pm and 1pm. During this period you cannot set the date, but you cannot damage the movement by attempting to do so.
So how does this actually work? When using the quick-change function at this time, the five-fingered star wheel will engage with the teeth of the date wheel in an attempt to move it along. The date change hammer prevents this from happening because it is also engaged with the teeth of the date wheel on the other side of the movement. Rather than allowing the pressure between these components to build, the lower level wheel beneath the star wheel is able to turn independently, allowing the force generated by rotating the crown to escape the mechanism. This is achieved by striking a perfect balance: The finely calibrated tension between the star wheel and the lower level wheel protects these components from coming under too much stress and disintergrating.
And if all this technology gets you so excited to skip past the intended date while using the quick-change function, don’t worry! The new NOMOS Glashütte DUW 6101 can be set forwards and backwards – a feature rarely seen in the world of watchmaking, and at this price point something very special indeed.
Thank you Rob!