Girard-Perregaux is not a name that many recognise, however their revolutionary watch, the Constant Force Escapement will definitely strike a chord with many watch aficionados. To put it simply, they have overcome one of the long standing issues with mechanical watches in a very unique way. I really should have written about this earlier.

What is an escapement?

As previously discussed in our article about Omega’s Co-Axial escapement, an escapement is a part in the watch that transfers the energy stored in a watch’s mainspring to the balance wheel (the part that keeps the watch’s time). In most watches, this component loses a tiny bit of energy and this has an impact on the watch’s accuracy. This is because as the spring uncoils to deliver energy, the power to the balance wheel also reduces. Some manufactures such as A. Lange & Sohne have tried to overcome this by using a fusee and chain, but the problem with this is that there is still a small amount of loss as well. It’s better than a traditional Swiss lever escapement, but not perfect.

Nichols Dehon who was a watchmaker working for Rolex at the time had an idea that came from bending his train ticket. He realised that if a blade spring was flexed between two points, it would snap back and forth delivering a predictable amount of energy each time. Dehon spent some time with Rolex developing a prototype but it was not until in 2008 when he was able to further develop his idea with the help of Girard-Perregaux. As a result, the GP Constant Escapement (aptly named also after the manufacture’s founder – Constant Girard) was born.


The heart – the Constant Force Escapement

Let’s look at GP’s press release video before we go any further:

As you may have seen in the video, as the S-shaped blade spring (that is six times thinner than a human hair) bends, it pushes the balance wheel. As the balance wheel comes back around it trips the impulse jewel which then allows the spring to snap back into its original form. The escape wheels and lever are made or pure nickel, and the impulse lever is silicon so that there is very minimal friction.

The movement is housed in a 48mm white gold case. Rather large but this is GP’s first production ready constant force escapement. In full view is the escapement itself and watching the movement tick along is quite a sight. The time telling dial is simple and modern, while a full sized second hand sweeps the entire case itself. A power reserve indicator sits neatly on the left hand side of the dial. Another striking feature of the movement are the blackened arrow-head shaped bridges that can be seen on the dial. The watch is designed to run for a full-week without winding, and reports from GP are that there is only a 2-second daily variation across this entire week.


Amazing detail on the caseback

Unfortunately only 10 will be produced and you’d be looking at a tad over AUD$100,00 for one of them. No doubt they have already all sold out. We’re very keen to see what else GP will be producing in future, perhaps a smaller sized watch would be ideal.


Assembling the movement