Urwerk UR-103.08 No. 04, TiAlN Steel

Well known in industry for its exceptional properties, the TiAlN (Titanium-Aluminum-Nitride) coating (less than 4 microns thick) has the effect of multiplying the resistance of the underlying metal to scratches, shock, oxidation and even acids. Applied to the UR-103.08, this offered the hardest steel coating known in the world of haute-horlogerie, fully-embodying Urwerk’s approach to combining horological art and cutting-edge technology. The colour of ‘TiAlN’ is dependant on the Titanium/Aluminium ratio, ranging from the bronze/aubergine colour seen on the UR-103.08, to a deep brown/black.

The increased durability of this coating is evident in the numbers. Although lighter than gold, TiAlN-coated steel measures 3500 Vickers in hardness - close to that of sapphire, at 4000 Vickers. This compares to a much lower hardness of 380 and 600 Vickers for gold and uncoated-steel, respectively. As explained by Felix Baumgartner, master watchmaker and co-founder of URWERK, “Profiting from the latest technical advances to continue developing our models is a must for URWERK. It was only after having seen and extensively tested the exceptional properties of TiAlN that we created our very first 103 steel case watch. The TiAlN appears to have the gift of endowing supernatural properties to common metals like steel.”

The reference UR-103.08 uses the same principles for its case design as others in the 103 collection, yet appears smaller on the wrist, owing to the colour given to the case with the TiAlN coating. With a sci-fi aesthetic, the case has a large crown recessed at 12 o’clock, as well as deep, linear, engravings running vertically on the curved case surface. With this direct lineage to the original UR-103, launched in 2003, and the later UR-103.03 ‘Targa’ (where Urwerk’s now-iconic revolving conical satellite indications were first exposed beneath a sapphire crystal), the watch measures at 50mm from lug-to-lug (36mm across). A thickness of only 13.5mm (including the lugs), allows for a comfortable fit beneath the cuff of a shirt.

Within the retro-futuristic case of the UR-103.08 is URWERK’s interpretation of wandering hours -  the complication in which the hour travels along an arc of 60 minutes, with the next hour appearing at the beginning of the arc, as the old hour reaches the end.  The 12-hours are arranged in groups of three on each of the four satellites, carried on four arms of a revolving carousel. As the carousel revolves, the four satellites successively pass over four Maltese crosses, rotating each satellite, with the hours following one another across the 60-minute sector. The hour-satellites are made from aluminium and the orbital cross in grade 2 titanium, coated with black PVD for maximum contrast. Against these dark surfaces, the numerals and minute markers are filled using luminous material.

Powering the wandering hours satellites is Urwerk’s manual-winding Calibre 3.03, beating at 21,600bph/3Hz, with a power-reserve of 43-hours. The reverse of the watch features a ‘grade 5’ titanium control board, where a power-reserve indicator is displayed, as well as the 15 minute and seconds dials for precise time setting. There is also a user adjustable fine-tuning screw that acts on the index which changes the rate of the balance, by altering the effective length of the balance-spring. The owner can thus adjust the rate of the watch to gain or lose up to 30 seconds a day. This was a feature commonly seen in Pocket-watches, often left un-sealed so the owner could easily open the watch and set the index fast or slow. However some makers, including Abraham-Louis Breguet, provided for adjustment without opening the case, as seen in this UR-103.08. Such a device is extremely rare in modern wristwatches.

The watch comes as a full-set, with box and papers from the manufacturer, and is fitted on the original brown alligator leather strap. This example is also fitted with a rare, original TiAlN tang buckle.

Viewings can be arranged in Central London by appointment.

Closer look

Brand:	Urwerk
Model:	UR-103.08 TiAlN
Movement:	manual-winding Calibre 3.03
Functions:	wandering-hours, power-reserve, 15 minutes and seconds setting display
Features:	TiAlN coated steel case, UR-103 case design
Case:	50 x 36mm
Crystal:	angular sapphire
Bracelet:	original dark brown crocodile
Box & papers:	full-set, box, papers