[h3]The Art and Science of Casemaking[/h3]
by Michael Friedberg
Hidden away in an quiet corner of Schaffhausen near the storied Rhine Falls in the tiny town of Neuhausen, stands a little-known Swiss IWC Manufactory.
While most of IWC’s watchmakers do their work on movements and assemble them in IWC’s main watch factory located on Baumgartenstrasse in the City of Schaffhausen, cases are produced in another facility tucked away on the Rhine.
Many might envision the art of watchmaking as involving a lone watchmaker toiling diligently, hunched with great concentration over his workbench, using what resembles tweezers and minute screwdrivers. With these intricate tools, talented workers put together a myriad of miniscule metal parts to fashion the ultimate timepiece. But, in fact, watch production involves a coming together of multiple craftsmen and as many disciplines. Each completed watch is in reality a synthesis of parts, including the all-important case. A finely made case not only protects the movement but also defines the design of the watch.
IWC is known for being a casemaker par excellence. Most of its watch cases, especially those that are complicated, are made at its new Neuhausen factory. The ground and second floors of this stand-alone facility are now primarily dedicated to making cases for IWC watches.
Few other watch companies make their own cases, and for good reason. The process is expensive and complicated, Because of the costs to create and maintain extensive machinery and to have expert personnel, most watch companies use outside suppliers for their cases. But controlling the case manufacturing process provides greater quality control and better flexibility in meeting production needs. It also separates a complete watchmaking company from others. A tour of IWC’s new facility shows that “in-house” production can have a special meaning when IWC produces the case.
Christian Loss, Department Manager for Industrialization Cases, recently explained the process for manufacturing IWC cases. Christian unapologetically is not a watchmaker, but a mechanical engineer with background in the dental industry. Christian’s extensive knowledge of machinery and manufacturing operations has well-prepared him for mastering watch case production. He recently explained the finely-tuned processes and heavy-duty machinery.
In brief summary, raw metal becomes a case in a series of steps:
• turning
• milling
• engraving
• surface processing, which consists of polishing, sand blasting, coating, satinage and numerous additional steps in different sequences.
• assembly
Between each step there is inspection, which also includes measuring.
What strikes the casual observer is the complexity of each task. The machines are sophisticated, and require precise computer programming. Each step involves a complex series of sub-steps. At every step and sub-step there is meticulous quality control, checking and rechecking. Producing a case at IWC becomes a true industrial achievement with measurable standards.
Most cases are made of steel, and the steel usually arrives as raw material in bars. IWC uses a special steel alloy, made for IWC only after undergoing extensive tests to assure that it meets IWC’s quality standards, especially for non-corrosion and wear.
In addition to steel, IWC also produces its own cases of gold, platinum and titanium at the Neuhausen factory. For precious metal cases, brass is used in the first instance, so the production can be tested before making an expensive mistake on the raw precious metal. All the casemaking machinery can be used to produce any of these metal cases. The main difference, aside from being especially careful with gold and platinum, is that heat in combination with titanium carries a much higher fire risk. Special precautions must be taken whenever titanium is fabricated.
The first operation applied to the raw metal is turning, which involves mostly symmetrical geometries. Turning means that the tool is fixed, and the part turns. One can imagine a metal rod or brick being turned or rotated symmetrically. Turning usually employed large, computer-driven machines which, due to their use, generate significant heat. Cooling, then, is important: a properly cooled machine can operate longer and with better quality. High pressure cooling is used, often with special cooling agents, allowing for faster cooling and therefore more cycles.
Milling usually occurs after turning. It is a totally different operation, since it can shape the metal with different geometries. In milling operations, the part is fixed and instead the tool turns. For example, the Da Vinci, Grande Complication or Aquatimer cases are especially complex and simultaneous five-axis milling is required to produce each case.
Some of the work in milling isn’t suited for large machinery, and instead hand-operations are involved. At each step, whether by large machine or hand-operation, there is meticulous quality control and measurement. We often talk about “fine-timing”, but in the world of fine machining “fine measurement” is required. Each item that is produced must meet extraordinary specifications. Often dimensions must meet measurement tests of within 1/100 of one millimeter. Depending on the item, some dimensions are tested for every single product, while others are sampled. Some are hand-tested and others computer-measured. The devil is in the details.
To accomplish this high-level quality, IWC uses also “lean manufacturing” principles, based on a system developed by a well-known automobile manufacturer. The essential idea is to produce more with more quality. There should no mistakes, and an aim for perfection —always. Even on a simplified level, all hand tools are laid out and ready in one box, so there can be less time or concentration gaps which might lead to errors. Every detail of every step in the process, and every tool used, is fully thought through in advance.
After milling, as needed, case components are engraved, again by computer-programmed machines. Engraving creates the images used on case backs such as for the Deep Two, Galapagos or Laureus models.
Movement parts, on the first floor at IWC’s new Neuhausen facility, are produced differently. The small, intricate parts are produced using spark-erosion, with wire as the raw material. In addition, plates are often decorated with perlage, Geneva Stripes or other decorations. Both the spark-erosion and the decoration machines are computer-driven. Again, regardless of the process or the machine, everything is checked and rechecked.
There’s also a climatized room, where Zeiss machines measure the produced parts precisely in microns. The ground floor, where milling and turning are done, generally checks parts by measurement, but on the first and second floor there are additional tests. Aspects of an item’s “look” are also examined: even sophisticated machines cannot tell if polishing is consistent and sufficient – hand-inspection and craftsmanship are required.
Polishing by hand, called “surface processing”, is done on the second floor. There are many steps to polishing each piece, and then as appropriate some sides or components are “satinized” or “sand blasted”. Some satinization is also done by machine: for example, Aquatimer case rings are satinized by machine since that’s the best way to achieve the necessary consistent quality, especially when there are sharp edges or complex geometry.
Polishing itself requires inspection at each stage, and then the produced item goes to a quality control laboratory on the same floor for further inspection. Even after passing quality control steps at each stage in the process, there is further review and quality testing at the end. Nothing is left to chance.
Within the final inspection by the third floor laboratory in Neuhausen, lacquer is applied. The finished case then finds its way to IWC’s original factory in Schaffhausen. There, a process known as casing up occurs: an assembled movement is inserted in the newly-produced case, and the dial and hands are applied. Another finely-crafted watch is born, the product of not only a special movement but an equally special case.
