Richard Mille UP-01

At 1.75 millimetres thick, fully cased, the latest from Mille is impressively durable given just how slim it is. Due in large part to its extensive use of titanium.

Necessarily doing away with a number of classical approaches to mechanical watchmaking in order to achieve this slimness, the novel caliber inside brings a handful of interesting touches to the table, most notably in the winding and setting works. While I'm not personally a fan of requiring a tool to wind or set the watch—particularly on a piece that's manually wound—the clutch to toggle between winding and setting appears particularly well engineered given the constraints at hand.

The dial being set in the same plane as the gear train is now commonplace in mechanical timepieces this thin, but Mille's approach lends the hands a comparatively improved level of resilience to any physical impacts the timepiece is likely to endure.

While I was somewhat concerned at first glance seeing them do away with the double roller and guard pin in the escapement, which are today standard shock-resistance safety features, upon further reflection it occurred to me that there are some workarounds Mille may have employed here that can neither be confirmed or denied in any of the promotional material I've seen and the 5000 Gs of impact resistance it was tested to speaks for itself.

One thing that is surprisingly notable in both the promotional photos and videos is the amount of dust and small fibers strewn about the movement, including a relatively large black fiber stuck to the top bridge of the going train right next the watchmaker's pointer finger in the above image. The voice-over talent in the linked video also gets some nomenclature wrong. At its 7-figure price point, one can only hope such oversights are not evident in the finished timepiece itself.

It's free-sprung, titanium balance wheel gets full thumbs up from me.

Image credit Richard Mille

O for Observatory

In a partnership between Phillips, LVMH-owned Zenith, and renowned independent watchmaker, Kari Voutilainen, a never-before-sold series of vintage Zenith 135-O movements (regulated by Charles Fleck and René Gygax in the mid-twentieth century for observatory trials) are being expertly finished, cased, and brought to market.

Featuring a stunted escape wheel to accommodate a larger balance wheel for improved rate stability, the movement architecture is akin to the Peseux 260, another vintage, observatory-grade chronometer, which Voutilainen based his own series of Observatoire timepieces on. However, unlike the Peseux 260, the Zenith 135 has an extra pinion in the gear train for a center-seconds hand, and can readily be set up to indicate either central seconds or subsidiary seconds. Whereas the Peseux 260 is architected specifically for a sub-seconds layout. That said, like Voutilainen's Observatoire timepieces and as with the Zenith 135-equipped timepieces that have preceded this set, Zenith has opted to go with sub-seconds.

It's also worth noting that, while Voutilainen converted the Peseux 260 to a free-sprung balance system for improved isochronism, he was very intentional about his team leaving the regulating components in the Zenith 135-O calibers they received exactly as they found them:

“The persons working on these movements were the best watchmakers at the time. They had the know-how to make things precise. That precision doesn’t disappear after 70 years. Our duty was not to touch that performance.”

Image credit Voutilainen / Zenith SA

Rexhep Rexhepi Chronomètre Contemporain II

The original Chronomètre Contemporain by Rexhep Rexhepi, which debuted in 2018, was a masterclass in movement layout and finishing. The follow-up from Rexhepi packs greater complexity under the hood, while retaining its visual identity on the dial side.

Surpassing the movement that preceded it in specs on paper, that increased complexity lends the new movement an altogether different visual appeal that falls a stride short of the supreme elegance of its forebearer. The supersized breadth of the anglage and oversized spokes on the balance wheel seem almost caricature-like when posed next to the original.

I would be interested to hear more from Rexhepi himself about the thinking that went into bifurcating power delivery and, in particular, the changes to the balance wheel. In addition to the unusually large spokes, the modifications to the variable-inertia weights on the balance render it moderately more tedious to make precise timing adjustments in such tight quarters. Robin Nooy, over at Monochrome, has reported that the balance screws are responsible for the 60% increase in inertia at the balance wheel. However, it is clearly the increased girth of those spokes that account for the majority of that increase. Ideally, though, you want to move as much of that weight as possible to the outer rim, or felloe, of the balance wheel to optimize rate stability. Time will tell if this new balance design has staying power or whether it will mirror the trajectory of Voutilainen's Carbontime Fused Quartz Balance in the Rexhepi timeline.

At the end of the day, the execution of the finishing remains world class and it retains a free-sprung balance, so it's still got it where it counts.

Image credit Akrivia