How To: Assembling A Watch Movement

Past weekend was a busy one with back to back Watch Events around the channel here. First we had the revamped Salon QP in London followed by Passion For Watches in Brussels. It is at the latter that I decided to sign up for a Watchmaking class organized by the Fondation de la Haute Horlogerie. As these classes tend to cost a pretty penny, I figured to give it a try so that after reading this you can perhaps decide if they’re worth the cost of entry (TLDR: Yes they are – I highly recommend these classes if you love watches, simply superb).

The watchmaking class took place in the Cercle Lorraine in the center of Brussels. The Cercle is located in the historic Hôtel de Merode, a former castle of one of Belgium’s oldest & most noble families. A beautiful setting and perfectly befitting this private watchmaking class. Our class had 6 tables foreseen which was a perfect size, allowing great interaction between classmates & teacher.

Our teacher of the day was a former Patek watchmaker and teacher from the Geneva Watchmaking school. We were all warmly greeted, seated & throughout the class were encouraged to ask questions. While I’m sure our teacher rocked it as a watchmaker at Patek, it seemed that he was really born to rock it in front of a classroom. Simply top notch.

Starting out, we understood the victim of the day would be a fully assembled UNITAS 6497. Each student had one of these movements in front of him on the desk & a set of just the right tools to be able to disassemble and reassemble this movement. The 6497 is essentially a pocket watch movement and has the great feature of not being made of a crazy amount of components. That of course makes it ideal for this introductory course. Mind you, the 6497 is an absolute workhorse movement that is found in an extremely wide range of watches, from Stowa all the way to Panerai.

We were briefly introduced to the world of schematics and assisted by a handful of slides projected in front of us. Prior to touching any tools or movement, we were given a few instructions on how to sit, how to avoid the shakes and a few other very good-to-know bits of info. The instructor essentially showed us a few key principles at his desk, after which it was all hands-on and ‘give it a try’ rather than show and tell. Really a great way to dive into the world of watchmaking.

Once I got used to the disassembly steps, the first moment where I had to focus a bit more was at the time we had to remove the pallet forkPallet Fork The pallet fork is a small lever in a mechanical watch movement that is part of the escapement mechanism. It is connected to the balance wheel and typically has two small, flat pieces called pallet jewels, which sit at the end of the pallet fork. These pallet jewels are also known as pallets. [Learn More] (pictured below). This fork is absolutely tiny and very thin. While it is easy ‘to grab’ this, it is also very easy to scratch and essentially wreck. I don’t think you want to have too much coffee running through your system when you’re looking at handling this little fellow:

Key ingredient to success was to neatly place every piece in the provided trays. The disassembly was much to my surprise, not too challenging. Of course, the teacher gave excellent directions so that helped (quite a bit). In addition to the assembly, we were also given further insights covering the inner workings of the movement. It was all genuinely interesting and you just don’t get this sort of immersive experience from reading a book on the same subject.

When fully disassembled, you’re essentially left with the base-plate and a tray full of Swiss puzzle pieces. Until now, the watchmaking process was quite a zen-like experience: just you, a few tools & the watch movement. Of course, it helps if you don’t have to worry about leaving a mark on the movement and a potentially terribly angry customer.

Once the disassembly was complete, we were all invited for a nice cup of coffee and cakes. During the break a very interesting watch talk ensued (because of course), and we were also shown the self-made watch by our teacher (no pictures, sorry). After a great coffee break and a good chat getting to know the group, we’re headed back to our desks. Now, the real fun would begin.

First hurdle was to place the wheels back in place. Which one goes first? And which side is up? Which side is down? Woops… Mind you the reassembly is much more challenging than the disassembly.

One of the top 3 challenging tasks for me was to place the bridgeBridges The bridges of a watch movement are the metal plates that hold the wheels and other components of the movement in place. They are attached to the main plate of the movement with screws. Bridges are used to support the balance wheel, the escapement, the mainspring barrel and other elements. Combined with the main plate they are the foundation of any watch movement. [Learn More] (below) back in order to secure the wheels (above) to the baseplate. You see, you somehow need to gently grip the bridge with your tweezers and in a perfectly flat sweeping motion place the bridge on top of the (very) unstable wheels. Any wrong move and at least one of the wheels will nudge to the side, making it impossible to secure the bridge and making it very likely to do some serious damage to the pivots if you aren’t careful.

Now, while placing the bridge correctly was quite challenging, it was not impossible. What I found the most challenging by far, was the final piece of the puzzle: The balance wheelBalance Wheel The balance wheel is a component of a mechanical watch movement that oscillates at a consistent rate. It receives a small impulse from the pallet fork, which is part of the escapement mechanism. The balance wheel is connected to a hairspring that controls the rate of oscillation of the balance wheel. The balance wheel and hairspring work together to keep accurate time. The oscillations of the balance wheel drive the timekeeping functions of the watch. The balance wheel is a crucial component of a mechanical watch movement. [Learn More]. The balance wheel comes with the hairspringHairspring The hairspring is a thin spring in a mechanical watch movement that is connected to the balance wheel. The balance wheel oscillates back and forth at a consistent rate, and the hairspring helps regulate these oscillations. The hairspring works by applying a restoring force to the balance wheel, which helps to keep the balance wheel oscillating at a consistent rate. The hairspring is also known as a balance spring. [Learn More], and that spring is very sensitive. We are told that we should very carefully place this element in the watch movement (which involves a sort of ‘sideways’ movement to add a bit of a challenge). Let me tell you, I’m quite confident I absolutely wrecked the hairspring as I must have dropped the balance wheel at least 10 times..

Best moment of the day was that moment where after way too many failed attempts I finally correctly placed the balance wheel. As soon as this piece completes the puzzle, the whole watch jumps to life. A very satisfying conclusion after spending a couple of hours trying to put this Swiss puzzle together:

Overall, I wholeheartedly recommend these classes for anyone with an interest in watches & watchmaking. It helps if you know something about watch movements before diving into one of these classes, though I guess it isn’t essential. In my class it seemed that everyone had a very good understanding of how a watch movement worked which made it a very fun and interactive class. The teacher was excellent, the facilities were great and the class went well above my expectations. If you have the opportunity to attend one of these near you, definitely take it into consideration!