Precision and tradition: exploring Nomos Glashütte's mechanical movements

From Hand-Wound to Automatic: The Unique Mechanical Movements of Nomos Glashütte explained in our feature article

Drawing on over 175 years of watchmaking heritage and tradition, Nomos carefully produce its timepieces, with the expertise of highly skilled watchmakers, in Glashütte, a small town tucked away between forests and hills, south of Berlin and near Dresden, located in the eastern Ore Mountains.

Founded by Roland Schwertner in 1990, today Nomos Glashütte is the largest manufacturer of mechanical timepieces in Germany. As an independent manufactory, the brand produces its own mechanical calibers in-house. To earn the title of "Glashütte" on the dial, a watch must have at least 50% of its value created in this historic watchmaking town. However, Nomos takes this one step further by producing up to 95% of its watch calibers' value in Glashütte.

Originally known for their accurate hand-wound movements, Nomos now produces both hand-wound and automatic calibers. They have six hand-wound movements, each unique and engraved with an individual movement number, perlage and ribbing polishes, and capable of chronometer-level accuracy.

Nomos automatic movements are also unique, with two extremely slender and precise automatic movements that can be produced in series: the neomatik calibers DUW 3001 and DUW 6101. The DUW 6101 also features a groundbreaking new date function.

To date, ten calibers feature a particular acronym engraved onto their backs: DUW. It stands for "Deutsche Uhrenwerke" (German watch movements) and underlines Nomos Glashütte's competencies as an independent caliber producer.

Production at Nomos Glashütte follows the principles of the Deutscher Werkbund (German Association of Craftsmen) movement. While cutting-edge technology is used when it helps precision, the vast majority of production is done by hand according to tradition and with a great deal of care and attention to detail.

The movements made in Glashütte have distinctive characteristics, such as the three-quarter plate and the gear train culminating in the escape wheel, a particularly robust and particularly beautiful construction with a good 150 years’ worth of tradition behind it.

The Glashütte stopwork, a part of the winding mechanism, has a long and curved jumper spring, unlike Swiss-made winding mechanisms. 

Enhancing the overall look, tempered blue screws get their cornflower blue color during a heating process. The final touch comes from finishes such as perlage, ribbing, and sunburst decoration.

Mechanical watches, whether hand-wound or automatic, may exhibit some level of variability in their timekeeping accuracy. This is due to various factors such as the wearer's activity level, changes in temperature and air pressure, minor impacts, and variations in how the watch is wound. 

However, mechanical watches from Nomos Glashütte achieve an accuracy of less than ten seconds deviation per day, which is a very good figure and not far from that guaranteed for chronometer-tested watches in accordance with the ISO 3159 standard.

The accuracy of a mechanical watch is largely determined by the precision of its caliber, specifically the escapement, a crucial component of a mechanical watch, with no other part requiring such a small margin of error. The balance and balance spring must work flawlessly in relation to each other, and the escape wheel teeth must be perfectly concentric. Even the slightest miscalculation can cause the entire escapement to fail. 

To achieve such precision, Nomos invested years of intensive study, experimentation, and prototype failures. But the effort were repaid. In 2014, Nomos unveiled its final escapement, the Nomos swing system. With this in-house escapement produced in series, Nomos was capable of something that few other companies in the world could match becoming independent of third-party suppliers.  

The tempered blue balance spring, at work in the Nomos swing system

After the first Metro model powered by the Nomos swing system, Nomos has begun to equip all its calibers (all of which are built in-house) with this solution. At some point all Nomos watches will have this tiny motor inside.

Another milestone was achieved in 2015 with the Nomos automatic caliber DUW 3001, flatter, finer, more elegant than everything that had come before. With this first caliber with neomatik technology, Nomos Glashütte set a completely new standard for its automatic calibers.

This caliber could hide itself from view behind a stack of nine postage stamps. At only 3.2 millimeters in height, it is thinner than any other self-winding watch produced in large-scale series, yet it still maintains exceptional precision. Virtually every component was assembled between the bottom plate and the three-quarter plate—in a space which on average is only one millimeter high.

One particularly challenging aspect of constructing such a thin caliber is the necessitation of a thinner main spring. It has—due to it consisting of less material—a weaker tensile force value. To make up for this deficit the caliber’s efficiency was increased: to 94.2 percent. There is effectively only 5.8 percent energy loss due to friction—normally this figure is around 20 percent. Despite a reduced design height DUW 3001 offers an exceptional caliber performance.

In 2018, Nomos introduced its first neomatik caliber to incorporate a date function. Notably, this caliber boasts an incredibly thin profile, measuring only 3.6 millimeters in height, thanks to the complete redesign and integration of the date mechanism. 

The placement of the date ring around the DUW 6101 movement allows designers to exercise greater creative freedom. Additionally, the date display is highly readable and up to three times larger than conventional date windows.

Each Nomos watch is subjected to a series of strict accuracy tests before it is released to the world. The rate of the watch is tested simulating various everyday stresses and strains, and then it must prove its precision again for a week in six positions. 

Nomos Glashütte's commitment to quality is evident in their watchmaking process, from dial design to mechanical innovation. Their proprietary swing system escapement is evidence of their dedication to precision and accuracy. 

Thanks to their capability to combine traditional watchmaking techniques with cutting-edge technology, Nomos Glashütte is poised to remain a leader in the world of fine watchmaking for years to come.