LUGS

The lugs are the attachment elements that secure the strap or a bracelet to the watch case. In the vast majority of cases, they are an integral part of the case and made from the same material.

Lugs are suitable for attaching bracelets of all materials (leather, metal, synthetic, etc.). However, there are alternative methods of attaching the strap to the case.

Bracelets made of precious metals are often welded directly to the middle part without an intermediary element. Sometimes, style dictates a single central attachment in place of the two peripheral lugs.

More rarely, some constructions have lugs attached to the case back or machined from the same block of material as the case.

It took over a century for the wristwatch to establish itself and ultimately replace the pocket watch at the dawn of the 20th century. Initially, wristwatches were primarily intended for women. Watchmakers often simply soldered “wire” lugs to a small pocket watch to attach a bracelet. The first lugs appeared at the beginning of the 20th century.

The major advantage of the lug attachment system is the ease of strap or bracelet interchangeability. In many cases, the lug design provides information about the watch’s manufacturing period.

 

Today, strictly artisanal case production has become quite rare. Depending on the design and complexity of the lug, the artisan typically uses a milling machine to shape each lug individually. The lugs are then either soldered with the help of a jig or, occasionally, screwed onto the middle part. The decoration (satin finishing, polishing, etc.) of the lugs is generally done before they are attached to the middle part; however, depending on the case design and construction, it can also be done after the lugs have been assembled to the middle part.

The method described here can also be applied on an industrial scale. Depending on the case design, construction, and materials used, the semi-artisanal method may be preferred over the industrial one.

Producing the lugs and the middle part in a single piece through machining is considered semi-artisanal. This method minimizes production costs, especially related to lug welding operations. The lug-middle part assembly is more homogeneous and robust compared to separately attached lugs. However, this method has the drawback of leaving less elegant milling radii at the junction of the case band and the lugs and does not allow the use of different materials for the case and lugs.

The method described here involves making the lugs and the middle part in a single piece through stamping. Depending on the case design, construction, and materials used, it can also be considered semi-artisanal depending on production volumes. The quality achieved through this method is optimal (no milling radii), and the middle part and the lugs are integral and therefore robust. Production costs decrease as production volume increases. Due to the initial high costs of tooling, this method requires minimum production volumes to be cost-effective and does not allow the use of different materials for the lugs and the middle part.

 

As is often the case in horology, new manufacturing technologies are closely linked to the emergence of new materials. Sapphires, composites, and ceramics have become prevalent in watchmaking aesthetics, demanding new manufacturing methods. Injection molding, machining, tools, and polishing are continually evolving to shape these new materials while meeting the technical and aesthetic criteria of a watch case.