Logbook of production, chapter 2: the cases
The second stage of production is the Union Collection case manufacturing. In the previous article, you discovered the process and creation of the flat and curved dials. Today, we will introduce you to the next chapter of our series and will discuss the savoir-faire of the case’s fabrication.
Before we begin, it is important to note that our cases go through a unique design process. Generally, the horns are an integral part of the case, but in Beaubleu, the horns come to encircle it and screw inside the case. The challenges of our design, therefore, lie in the adjustment of parts and the treatment of surfaces. An exciting process but not without risk.
April 18, 2020
Let us start the manufacturing of the cases! Suffice to say that, for now, these are simple blocks of steel, and it will be a long journey before the results. To go from the draft to the result, you must follow different stages interspersed with measurement and annealing operations.
The first step in creating the middle of the case is the modeling of the steel block. It is a simple block that will be successively compressed and flattened ten times using rolling mills – machines made up of hardened steel cylinders. This stage changes the metal quality to create a compact solid shape. Each piece will have to pass the dimension test because each variation will be visible on the final product. Nothing we can’t handle!
May 5th, 2020
Today, we are in the workshop to check the first pieces of the stamping stage. We will discuss with our craftsmen the various difficulties encountered and viable solutions.
The stamping operation, which would be like cutting, consists of shaping the medium with a stamp that crushes the material. Repeated several times, the metal gradually regains its shape. Between each stamping, the part is annealed and remeasured.
We begin to see the first elements of the Beaubleu watch horns. They are worked separately, and at this stage are only a silhouette of the design. We remain ruthless in the face of quality, and non-conforming parts are entirely reworked.
May 18th, 2020
Once the stamping process is finished, the piece is now ready to begin the machining stage. The machining process is an important step, and failure at this level of manufacturing can result in significant costs. This step consists in sculpting the final shape of the parts, focusing on the mechanical aspect, i.e. ensuring the placement and drilling of the screws, the adjustment of the parts between them (case horns and movement), and the quality of the shapes (chamfers, fillets, curves, and solids).
At this stage, we finally have before us the Beaubleu pieces. The horns are hollowed out using an arm capable of positioning on five axes. This technique is called CNC 5-Axis Use and is intended for small series. In our case, it is the most advanced technology to obtain the expected result. The horns’ slenderness and position must be treated first by computer-controlled machines and after by hand.
Alex, a machining specialist, sums up our day with a laugh: “Your horns are beautiful, but hell to do.” In order not to spoil anything, pieces are precise to a tenth of a millimeter, with each part remeasured and redone from the start if it is considered non-compliant.
May 30th, 2020
We knew it, but the machining step being extremely delicate, several parts were not in conformity: deformations of certain parts due to metal variations and other unexpected “pleasures”. So, we stay calm and begin again. Luckily, this has no impact on production times, which is a victory.
June 10th, 2020
Considering the past few days and the relaxation of government working conditions regarding Covid-19, we are now entering the most beautiful stage: the treatment of surfaces. We have gone from a big block of steel to a rough watch. Now it is time for a final look at the metal of the Union collection: grained and polished. All visible parts are placed in a sealed box where very fine sand will be thrown at high speed. Abrasion of the steel will then give this grainy, almost powdery appearance. The challenge here is to better control the grain size to obtain homogeneous and delicate graining.
June 16th, 2020
The next steps is polishing. Using a lathe, the parts are polished, being extremely careful not to protrude from the grained surfaces. Despite the loud noise of the machines, the workshop is plunged into religious silence for the concentration of each craftsman. A single movement can damage the sanded surface and if this is the case, we must start sanding completely.
Another element must be considered: the quality of the surface. Aside from the absence of scratches, the qualified experts, and our designer Nicolas, check the light and environmental expressions on the watch. It is like the body of a car, the reflective design will tell you if the part is “veiled”, concave, or convex. It is a question of experience at this level because if you remove too much material from the polishing, it is the assurance to start the part from the beginning.
There is a special mention for the hollowed-out ropes. Since no power tool is small enough to polish the interior, the finishes are done entirely by hand. Great progression!
June 22nd, 2020
A small routine check on the first steel watches begins. The angles of the parts are well controlled, and we see ourselves in the polished surfaces. Some parts have been reworked to meet our quality requirements.
Today, there are still different stages, such as the processing of certain models such as the Audace or Olympe from the Rive Gauche line, and of course the final assembly. In the meantime, we will focus on our signature round hands and their manufacturing process.