Introducing the Panerai Radiomir 1940 3-Days Automatic with Panerai’s First Micro-Rotor Movement

Off all things we could expect, this was certainly not on our short list. Panerai just introduced their first in-house movement with a micro-rotor. The new P.4000 movement will be officially launched at the Watches & Wonders fair (yes, it’s that season again) in the 45mm large Panerai Radiomir 1940 3-Days Automatic that will be available in stainless steel (Accacio) or rose gold (Oro Rosso.) Let’s have a closer look at this ‘elegant‘ new movement from the brand that is (or was?) inseparable from its military heritage.

Every mechanical movement powered by a micro-rotor is simply a bit different from any mechanical movement with a full rotor. Of course, the differences are obvious, but for collectors the micro-rotor powered movements are always a bit more special. Micro-rotor movements have the imago of being a touch more refined, they are loved for not obscuring the beauty of a movement (a full rotor does exactly that) and being more part of the entire design of main plate and bridges.

Although collectors also are well aware of the fact that it’s harder work for a small rotor to ‘harvest’ enough energy to power up the main spring, where as it’s much easier for a full rotor. Still the micro-rotor has found a special place in the hearts and minds of collectors. An additional explanation for the micro-rotor’s popularity among the purist collectors, might be that it’s mainly used by very refined brands, like Patek, Parmigiani, Piaget or Chopard, for very refined timepieces. And now Panerai, a brand undeniably connected to HUGE military inspired timepieces, comes with such a movement. And they chose to launch the new Panerai P.4000 movement in two Radiomir 1940 models.

The Panerai Radiomir 1940 3-Days Automatic

The Radiomir 1940 3-Days Automatic comes in a 45mm stainless steel or rose gold cushion-shaped case. The Radiomir 1940 line differs from the older well-known Radiomir line, with different lugs and crown. Where the normal Radiomir has so-called wire-lugs, the new Radiomir 1940 has normal straight lugs. The new Radiomir 1940 has a screw-down crown, which looks like a Rolex trip-lock crown, however with the Panerai logo embossed.

The steel version (PAM00572) comes with a black dial with cut-out numerals and baton indices. A second dial, placed underneath the black dial, entirely covered with luminescent material, ensures that the numerals and stick markers shine bright at night (when they have been exposed to light during the day, that is.) The red gold version (PAM00573) offers the same, however the dial is brown.

Other versions of the Radiomir 1940 collection (such as the Chronographs), comprise models with a diameter of either 42mm or 47mm, and are all equipped with manually wound in-house movements.

Panerai P.4000 movement

Now back to Panerai’s new micro-rotor calibre, the P.4000 movement. As the name of the two watches already indicates, we’re talking about a movement that has 3 days of power reserve (when fully wound). This energy is stored in 2 main spring barrels which are connected in series. The movement measures 31mm in diameter and is 3.95mm thick. The latter is mainly due to the use of a micro-rotor, because that’s mounted off centre, within the movement, and thus does not require more space for a large centrally mounted rotor that logically adds thickness.

Panerai chose to create two versions of the movement, each matching the aesthetics of the case. The stainless steel watches will have bridges with a horizontally brushed finish, blue engraving and a micro-rotor of tungsten with a bas-relief decoration with the brand’s name and logo on a matte surface. The gold cased watches will have a more luxurious choice of materials, with bridges having a circular brushed finish and gilded engraving, with a 22K rose gold rotor with a clous de Paris hobnail pattern and polished decorations (the brand’s name and logo) in bas-relief on the brushed surface.

Officine Panerai says the new P.4000 movement is completely developed and made in the manufacture at Neuchâtel. With a diameter of 13 3⁄4 lignes (approx. 31 mm), the new calibre has a large bridge which is flanked by the small micro-rotor and the balance bridge. This bridge has two screws for adjusting the vertical play of the balance staff. The balance wheel, with variable inertia, vibrates at 28,800 vph (4Hz) and features screws enabling the rate to be adjusted precisely without altering the balance spring or bridge. The movement has 31 jewels, and is fitted with a so-called hacking seconds mechanism that stops the second hand when the crow is pulled.

Panerai did not give any information about the height of the new Radiomir 1940 watches, so it’s not clear whether the case is much thinner than before. And that is usually the main reason for opting for a more complex, and often more fragile, micro-rotor movement. For now it seems like a very nice new movement, however the reason for creating a micro-rotor movement – usually to make a watch thinner – remains unclear. We’ll keep you posted when more news becomes available.