Monochrome Watches
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The Last of the 105 Series, the URWERK UR-105 Tantalum Hull

The farewell edition of an ultra-cool watch, clad in titanium and tantalum.

| By Brice Goulard | 5 min read |
URWERK UR-105 Tantalum Hull

In order to create something new, you sometimes need to kill what’s already existing. Some brands love to look at their past – or heritage to use fancy names – and some, on the other hand, only move forward. URWERK is part of the latter category and is known for having already take radical decisions. To remain true to themselves, to remain independent, the production is capped to about 150 pieces per year. And this means that to bring a new creation, an older one has to be killed. This happened with the UR-210, leaving room for the UR-220. And it is now happening to a watch created in 2014, the UR-105, which is now leaving its last days… but before, there will be a final edition to celebrate, the last of the 105, with the URWERK UR-105 Tantalum Hull.

The first of the 105 series, the hand-wound UR-105M launched in 2014

URWERK is a brand like no others, and for multiple reasons. The company, co-founded by watchmaker Felix Baumgartner and designer Martin Frei, is all about creativity, whether mechanical or visual. URWERK doesn’t try to appropriate existing concepts, they have built watches that are original works, which display the time in a different way, which are designed with shapes that no other watchmaker are using. And, whether you like them or not, these watches create emotions. With a yearly production voluntarily capped at about 150 watches, in order to remain true to their original motto of exclusivity and to remain independent, the brand needs to take decisions when it comes to renewing collections, to launch new models “This means that we reluctantly have to ‘kill’ a collection to bring a new creation to life. And time for the UR-105 CT is now running out,” says Felix Baumgartner.

The UR-105 has become part of the independent watchmaking landscape, having been created in 2014. This watch was, and still is, a true URWERK in all aspects. It was launched next to more complex models, such as the 200 series, and thus was a more focused vision of the co-founders’ ideas. Still, with its signature display where time is indicated by four orbiting and rotating satellites, as well as the presence on the caseback of the iconic control dashboard, there was already a lot going on with this true-to-basics model. It was also an ode to previous watches, as combining the display of the 103 series with the angular shapes of the 200 series. While the first models were hand-wound, the second generation of UR-105 will be automatic, and feature the automatic winding position lever and self-winding mechanism regulated by two turbines on the caseback. There will then be multiple iterations, such as the bold T-Rex, the Clockwork Orange, the Raging Gold or the Streamliner.

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URWERK UR-105 Tantalum Hull

And now, the farewell edition is here… The URWERK UR-105 Tantalum Hull – once again an oddly cool name for a watch that has a lot to show. If the overall shape remains true to previous editions of the UR-105, including the hinged protective cover which is opened by activating a sliding “tongue” on top, the materials are new. Measuring 39.5mm in width, 53mm in length and 17.8mm in height, the 105 is a watch with a presence, and this will even be reinforced by the use of a rare and fascinating material, tantalum. Used for both the protective cover and the top bezel, tantalum is an extremely hard metal with a blue-grey lustre and a weight close to that of platinum. But despite its beauty, it is also a nightmare to machine and to finish. But, as said by Baumgartner, “tantalum is one of the most URWERK-ian metals I know of. It is dark, almost anthracite-coloured, a shade which is an integral part of URWERK’s aesthetic signature.” And we couldn’t agree more.

The UR-105 TTH, or UR-105 Tantalum Hull, once again plays on geometric lines and avant-garde design cues. Its case is sharp, textured on the sides with vents, the crown is oversized and positioned at 12 o’clock and the protective cover is decorated with vertical grooves and a circular brushed finish. In order to maximize comfort, the weight of tantalum is compensated by the use of titanium for the central container and caseback, which are both black coated and matte finished.

URWERK UR-105 Tantalum Hull

Opening the cover by using the slider has always been a true pleasure. When closed, it leaves only crucial indications visible. When opened, the true mechanical beauty of URWERK is revealed, with a view on the satellite time indication, which for the occasion is built on a new skeleton carousel. The latter supports four hour satellites, each displaying three hour numerals that rotate in turn along the minute track, providing both analogue and digital time displays. In addition, the UR-105 Tantalum Hull also indicates a power reserve on the lower right side, and the seconds by the mean of an ultra-light disc made using the LIGA photolithography process and displaying 10-second increments (The total weight of the display is less than 0.10 grams…)

URWERK UR-105 Tantalum Hull

The back reveals a true URWERK function… the iconic turbines to regulate the movement’s automatic winding system, and the lever to select the desired function. In Full position, the slightest movement of the wrist is enough to wind the mainspring. In Reduced position, the two turbines moderate winding to minimize excessive tension and wear. In Stop position, the automatic winding system is deactivated and the UR-105 is manually wound. At the heart of the watch is an outsourced automatic base movement, with on top an in-house module to indicate the time. The movement runs at 4Hz and boasts 48 hours of power reserve. The decoration includes perlage, bead blasting, frosting and screw heads with polished bevels.

URWERK UR-105 Tantalum Hull

The URWERK UR-105 Tantalum Hull is worn on an innovative and textured Vulcarbon rubber strap with black DLC buckle – which was already found on the UR-220 Falcon Project. It will be a limited edition of 12 pieces only, priced at CHF 77,000 (excl. taxes). Now comes the question of what will be the following watch… A new UR-106? We’ll know soon enough.

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