23.07.2019
The regulating organ
A fitting tribute
When Frederic Chopin passed away in 1849, his heart was immersed in Cognac and repatriated to his spiritual home, Warsaw. While the remainder of Chopin’s body is buried in Paris, his heart will live forever in Warsaw, enshrined in a pillar within the Holy Cross Church. Chopin’s heart is of symbolic importance to the citizens of Poland, conferring an emotional connection between the legendary composer and his compatriots.
Prior to the unveiling of its inaugural watch, the Chopin Op.10 No.12 timepiece, the Polish firm sought to reference the composer’s heart within the model’s design. A circlet of carnelian is incorporated beneath the small seconds display. Its red hue, visible from the side, provides a visual metaphor for Chopin’s entombed heart.
Chopin Watch also chose to reference the composer’s heart with a red balance wheel. The combination of the balance wheel and hairspring is termed the ‘regulating organ’. Sometimes the regulating organ is called the ‘heart’ of the watch, providing an obvious symbolic link to Chopin’s heart.
The purpose of a regulating organ
When the winding crown is rotated, the mainspring is tensioned. In the case of the Chopin Op.10 No.12 timepiece, the movement contains two mainsprings, a detail I will return to in the future. When the mainspring is fully tensioned, it harnesses much energy.
The mainspring, sitting within a spring barrel, unwinds and the teeth affixed to the exterior of the spring barrel engage with the gear train, causing the wheels to rotate. If the energy is allowed to pass through the gear train without impediment, the hands would rotate too quickly. Such extreme torque could also damage some components and the hands would cease to move after a short period of time.
In order to prevent this happening, the gear train is connected to the escapement, comprised of the escape wheel and pallet lever. The pallet lever pushes the regulating organ which in turn, oscillates to and fro at a predetermined frequency. At the same time as supplying energy to the regulating organ, the escapement momentarily suspends the motion of the gear train before a defined period has elapsed and the gears are able to move again. It is the constant repetition of this process that controls the flow of time, ensuring the hour and minute hands indicate the correct time.
The red balance wheel – overcoming the challenges
As stated earlier, Chopin Watch sought to incorporate a red balance wheel within the movement. This necessitated the balance wheel being coated with red PVD treatment, save for its underside. Chopin’s strategic partner, movement specialist Schwarz Etienne, was tasked with suffusing the surface of the balance wheel with a red tint.
The application of the red PVD to the balance wheel proved incredibly challenging given that the thickness of the coating had to be consistent. Schwarz Etienne, one of the few companies which makes regulating organs, had to work to infinitesimal tolerances. If there was just a slight variation in the coating’s depth, the balance wheel’s moment of inertia would fluctuate wildly, effectively making it impossible to set the rate of the movement.
After expending much time refining the application of red PVD to the balance wheel, Schwarz Etienne fulfilled the requirements of Chopin Watch. This would not be the last time that Chopin Watch utilised Schwarz Etienne’s immense creativity and impressive technical expertise.
An in-depth look at the regulating organ
In the beginning, Chopin Watch looked at various companies to collaborate with. One firm stood out, Schwarz Etienne, a Manufacture based in La Chaux-de-Fonds, the watchmaking capital of Switzerland. This long-established firm, founded in 1902, makes its own watch movements.
As mentioned previously, Schwarz Etienne also makes its own regulating organs, a rare skill in the watch industry. The hairspring is the horological equivalent of alchemy. The spring has to be elastic, corrosion resistant, temperature resistant and breathe concentrically. The composition of the alloy used for making hairsprings is shrouded in secrecy.
The alloy is supplied as a wire, delivered on reels. A series of state of the art machines stretches the wire, making it increasingly thinner. This rolling process takes a long time and cannot be rushed. The circular profile of the wire is transformed into a flat blade. Each blade is cut to length, coiled and baked in a specialist oven. Again, the details of the baking process remain secret.
After the hairspring has been made, it is affixed to the balance wheel’s ‘collet’ using a precision laser. Once the balance wheel and hairspring are united, they need to be poised. Just in the way a car wheel and tyre are balanced with suitable weights, the balance (balance wheel and hairspring) has to run true. The underside of the balance wheel rim is cut in order to achieve a wobble-free result.
A key factor which influences the performance of the regulating organ is the concentricity of the hairspring. The hairspring should breathe evenly. If the hairspring, while oscillating, is biased to one side, this will impair precision. It therefore has to be set up correctly by a competent watchmaker.
While the inside coil of the hairspring is attached to the collet, the outside is attached to the stud. The stud sits in a holder affixed to the balance bridge. Adjacent the stud is the regulator. When the regulator is moved towards or away from the stud, it increases or decreases the effective length of the hairspring which in turn makes the watch run faster or slower.
Closing remarks
This technical insight provides an overview of the many issues which must be considered when creating a new watch. Chopin Watch, together with its partner, Schwarz Etienne, has surmounted various challenges in order to create a worthy tribute to one of Poland’s favourite sons. Moreover, beyond its aesthetic allure, the Chopin Op.10 No.12 timepiece is imbued with much watchmaking know-how and confers impressive accuracy. After all, as Chopin clearly demonstrated, timing is everything.