Among the heavyweights of the Portugieser Collection, IWC revives the brand's successful tourbillon mechanism with constant power transmission.
Today, IWC is a brand known for its pilot models and simple but useful models designed per the Tool Watch concept. When we look at the last ten-year period, we see that the models highlighted by the brand are chosen following this approach. However, IWC also has a solid history in high watchmaking and grand complications. Though we cannot see the present reflections of this past in the models that are the subject of press releases or advertisements, this does not change the fact that grand complication models have always been present in the product line of the brand.
The model that we are focusing on for review today is exactly among the watches I mentioned above. The IWC Portugieser Constant-Force Tourbillon follows in the footsteps of the Sidérale Scafusia, the most complex (and expensive) watch the brand has ever designed.
The IWC Portugieser Constant-Force Tourbillon comes with a 46mm diameter and 13mm high case. The case is indeed quite large for a dress watch or even a Portugieser. However, considering the functions of the model, we can even call it a compact case. The model we chose for review comes in a platinum case. There is also an 18K rose gold version of the same case. By the way, let me remind you that IWC offers the customer the opportunity to customize the watch, albeit limited.
The model has a remarkable dial. The dial, finished in anthracite tones and sector style, features the Tourbillon cage resting in all its glory at 9 o'clock. Although the escapement, which is fixed in place with X-shaped bridges, looks very large at first glance, it handles a very serious task due to its size, since it carries the constant-force transmission mechanism on it (which I will return to a little later).
At 1 o'clock, the dial features a moon phase disk designed to resemble the cratered surface of the Moon and a dual hemisphere moon phase indicator. Just below this, is the power reserve indicator.
The model is powered by the manufacture Caliber 94800. The hand-wound movement comes to life as a version of the Caliber 94900 in Portugieser Sidérale Scafusia, with the astronomical module and Sideral Time features removed and replaced with IWC's famous double moon phase indicator.
Another feature in the movement, constant-force Tourbillon, is an engineering marvel in its own right. The small spring located just below the escapement wheel accumulates and releases the power in the mainspring at a frequency of one second. This mechanism, which enables the escapement to be powered by a small but constant energy source, keeps the balance at a constant amplitude and provides a rotation that moves in one-second steps to the tourbillon cage. However, this only applies for the first 48 hours of the 96-hour power reserve, when the mainspring is wound up enough to provide enough power to keep the constant power mechanism running at optimal speed. Once the two-day limit is exceeded, the constant force is deactivated and, the tourbillon works like a traditional tourbillon. It doesn't look like a Tool Watch at all, does it?
The IWC Portugieser Constant-Force Tourbillon comes with a black alligator strap and a platinum folding buckle, made by Santoni, decorated with white stitching. As I mentioned before, the model can also be ordered with different case/dial/strap options.
