Audemars Piguet Royal Oak 37 Double Balance Wheel Openworked
Openworked or skeletonised watches are treats for the more mechanical-minded admirers of watchmaking, and the more complex the movement, the better. In 2016, Audemars Piguet increased the viewing pleasure two-fold when it unveiled its Audemars Piguet Royal Oak 37 Double Balance Wheel Openworked ref. 15407. As its name indicates, the movement was equipped with two balance wheels, one exposed on the dial of the 41mm watch. The latest duet to join the collection are two models with 37mm diameters in white or pink gold powered by the in-house calibre 3132. However, the novelty here is the tone-on-tone palette that matches the colour of the case material with the movement.
The “two is better than one” premise behind the Audemars Piguet Royal Oak 37 Double Balance Wheel Openworked , explained in this video, features two balance wheels to increase chronometric performance and stability. However, to access and regulate each balance spring individually, AP’s watchmakers placed the two balance wheels and two hairsprings on a single axis but separated them, with one visible on the dial and the second on the reverse side.
While the 41mm version is more prevalent, the 37mm version of the Audemars Piguet Royal Oak 37 Double Balance Wheel Openworked is not new. It appeared in 2018 in a gorgeous, frosted gold case. Today, AP presents two 37mm editions: one in white gold with a rhodium-toned movement and the other in pink gold with gold-toned finishes. The familiar geometry of the Royal Oak is highlighted with satin-brushed and polished finishings.
Openworked movements, which remove as much material as possible from the mainplate and bridges to let the light through and reveal the movement, have existed at AP since the 1930s. In tune with the times, AP now uses CNC machines to cut the bridges into the desired shape and finishes them by hand using more traditional techniques.
The labyrinthine network of bridges reveals the intricacies of self-winding and patented calibre 3132. One of the balance wheels twirls between 7 and 8 o’clock on the dial, and the other is visible on the caseback. Other components, like the gear train and the mainspring, are clearly visible on the dial. The balance wheels beat at 3Hz, and the gold openworked delivers energy to the rotor for an autonomy of 45 hours.
The rhodium-toned bridges and movement of the white gold version are punctuated by touches of colour provided by the rubies and the light blue inner bezel with the applied and luminescent white gold hour markers framing the dial.
With its pink gold-toned bridges and movement and vivid purple flange, the pink gold model has a more opulent personality. For contrast, the hands and indices are crafted in white gold and treated with a streak of luminescence. Both models come with integrated gold bracelets, an additional light blue alligator strap for the white gold model, and a purple alligator strap for the pink gold with gold AP folding clasps.
