Title image courtesy of Phillips.

September 2021 15 Min Read

The Art of Dial Finishing

By Tony Trania

The dial. It’s the face of the watch, the element of the timepiece we look at most often, and the component that we form an emotional attachment to. Just a few microns thick, these watch dials carry the distinctive styles of each watchmaker, acting, in many senses, as the face of the brands themselves.

Alongside the different forms of movement finishing, watchmakers through the ages have paid equal attention to the techniques used in dial finishing. After all, without the dial and its varying ticks, indices, windows, and sub-dials, the gears and springs of the movement remain uninterpretable to the untrained eye.

The straight lines of a hand engine-turned dial on a Vacheron Constantin watch, courtesy of Phillips.

Like many other aspects of watchmaking, these dial finishing techniques lie at the intersection of art, human skill, and engineering. Before an artisan begins shaping a dial, it is a mere metal “blank” of highly polished brass, silver, or other metal. The application of finishes then adds texture, pattern, and structure to the dial, transforming the unmarked metal into a work of art through a combination of artistry and innovation. Techniques such as guilloché have existed for centuries, they have been carefully handed down from one to the next, with the current generation just as proud to carry on the tradition as they are keen to ensure it is passed on.

We have previously discussed the art of lacquer dials (with a focus on Rolex’s vibrant Stella dials) and separately enamel. Instead of focusing on materials, here we will examine dial finishing techniques in greater detail, exploring engine turning, frosting, hand-hammering, along with other methods that have come together to create a rich spectrum of dials through history.

Engine Turning (Guilloché)

Engine turning, also referred to as guilloché in French, is perhaps the most traditional method of dial finishing. According to Joshua Shapiro, an American watchmaker who specialised in the guilloché, engine turning is the “process of using a sharp cutting tool to carve geometric patterns into metal”. To create a dial using this technique, a rose engine machine is used to engrave a precise, repeating pattern into a metal blank. These designs can take the form of mesmerising rosettes, basketweave patterns, or diamond “hobnail” shapes.

An antique engine turning machine used for guilloché, courtesy of Studio Celia, with an original Breguet that showcases multiple patterns, courtesy of Swiss Watches Magazine.

Engine turning began as a form of decoration for objects of all types, dating as far back as the sixteenth century. Rose engine machines are large, expensive, and hand-operated, meaning that this technique was purely ornamental, used only to decorate objects for the wealthy. This principle was carried over to watches, as in his book, Watchmaking, George Daniels notes that “the complication of the work and the skills required confined the process to the most expensive hand-made watches.”

The first engine-turned watch appears in 1680 from a Genevan watchmaker named Pierre Duhamel. More than half a decade later, Abraham-Louis Breguet began to use engine turning on his dials. While he may not have been the first to utilize engine turning on watch dials, because Breguet’s pocket watches were so popular, he, in turn, encouraged the growth and development of this technique. Additionally, because his movements were so complicated, he would often used a range of different patterns to help differentiate between the various sub-dials of the complications.

Breguet No. 217 which utilises multiple guilloché patterns to distinguish between its various sub-dials, courtesy of Haute Time.

With the advent of the Industrial Revolution around the turn of the twentieth century, guilloché became more popular as engine turning machines could be mass produced. By the 1930s, the technique made its way into wristwatches, and it can be found in many watches through the 1950s.

“My favourite wristwatches from this era are Vacheron Constantin watches with engine-turned dials,” watchmaker Josh Shapiro of J.N. Shapiro Watches, says. “They did an excellent job of creating very complex patterns, and their watches were very thin, which meant the dials were very thin too. This makes it very difficult because the engine turning process removes material from the dial, so if you go too far, you’ll go through the dial.”

Modern Engine Turning

While engine turning flourished through the middle of the 20th century, it nearly became extinct by the 1970s, as changing tastes and then the quartz crisis decimated the practice. However, it saw a slight revival in the ‘80s and ‘90s, with practitioners like George Daniels pushing the art into the modern era.

Daniels dedicates an entire chapter in Watchmaking to the art and use of the traditional rose engine turning process, and today, this chapter is often thought of as the “bible” for those seeking to learn more about the engine-turning technique, including for those outside of watchmaking circles. In addition to being one of the most important horologist of the 20th century, Daniels was also a master engine turner who helped resurrect the practice towards the end of the century.

Now, modern artists are ensuring the art and technique is practiced and passed on to another generation of artisans and watchmakers. At the forefront of this movement is Josh Shapiro, a watchmaker based in Los Angeles, California, and founder of J.N. Shapiro Watches.

“Engine-turning is a fascinating combination of art, skill, and machine technology,” Shapiro told us. “All three of these need to persevere for engine-turning to survive. For me that means being creative with pattern possibilities and applications, always trying to improve one's skill, and lastly taking great care of my machines and to help make sure others are able to acquire the machines.”

Joshua Shapiro’s engine turning machine, courtesy of The Horological Society of New York.

Shapiro emphasized the importance of tooling in guilloché. Rose engine lathes are large, complicated pieces of machinery. It either requires significant time and investment to build a rose engine, or the same sort of investment to find, restore, and maintain an old machine. A rose engine lathe is comprised of a large “cam” that rotates around an axis. The cam is essentially a disk that can be shaped into all manner of geometric patterns — also called rosettes, hence the engine’s name — which the touch piece that holds the metal blank essentially “traces” in a mechanical manner. The operator then hand-applies pressure to the cutting tool to carve the pattern into the metal blank. Crucially, the cutting tool itself is completely stationary during the process, and it is the cam that is rotated and shifted to create the motifs. These machines require an enormous amount of skill to operate, as if too much pressure is applied, the cutting tool can cut through the dial, while uneven pressure creates irregular patterns and dials quickly become scraps. The dexterity and control needed to carve such a tiny disk of metal is a true testament to the watchmaker’s mastery of their craft.

The infinity weave pattern that Shapiro patented, courtesy of The Horological Society of new York.

Referencing the early guilloché work of Breguet, Shapiro had this to say: “What I find neat about it is that [between] what the engine turner did and what I’m doing now, we could probably switch machines and figure out what the other is doing fairly quickly. The basics of these machines are timeless.” It is this lineage of artisanry that continues to fascinate and captivate practitioners and collectors alike, allowing engine turning to experience a Renaissance in the 21st century.

Common Guilloché Patterns

Straight-line engine turning is similar to rose engine turning, but instead of repeating geometric patterns in a circular arrangement, a pattern is repeated across the dial in a straight line. Rather than following a rotating cam rosette to create a geometric pattern, the touch piece follows a pattern bar that guides it to engrave the desired pattern.

The most common engine turning pattern, and the easiest to execute, is a diamond pattern, often referred to as Clous de Paris, or hobnail pattern. While the hobnail pattern might be most closely associated with the bezel of certain vintage and most modern Patek Philippe Calatravas, it has also been executed on dials by various manufacturers over the years.

Take, for example, the hobnail pattern present in a number of Kari Voutilainen’s pieces. Each peak formed by the overlapping diamond of the Clous de Paris pattern creates a nearly microscopic flat surface on the top of the peak. This requires perfection not only in the execution of the engine turning pattern, but also on the dial blank itself; if the metal is not completely flat, its imperfections will be visible after the dial is finished.

Four of the more common patterns of guilloché.

The most difficult guilloché pattern to execute is the “basketweave,” a pattern of mirroring and overlapping lines with sharp 90-degree angles.

“The basketweave is the most difficult of patterns that you will see in many different watches,” Shapiro said. “One of the reasons for this is in order for the pattern to look great, all the squares need to be at perfect 90-degree angles. Any rounding of the corners and the pattern doesn't look as good. That is the real challenge with the pattern.”

Shapiro points out that some larger brands will achieve this perfect 90-degree angle simply by engraving straight lines and then rotating. Shapiro uses a pattern bar to create his basketweave pattern, which are metal templates that allow parallel or radial lines to be created on the disk. This is the traditional way of creating the pattern, a technique pioneered by Breguet.

As one of the most accomplished modern practitioners of guilloché, Shapiro has also played a part in advancing the art form by developing a unique pattern which he calls the “infinity weave.” It’s basically a basketweave inside of a basketweave, and can take a week of work by itself just to complete a single dial.

Joshua Shapiro’s trademark infinity weave, a complex pattern that layers basketweave patterns onto the dial, courtesy of Hodinkee.

“The infinity weave was created because I wanted to push myself technically. I wanted to do something that would differentiate me from other engine-turners in the world,” Shapiro said. “The pattern is also very beautiful [when viewed] both with the naked eye and with a loupe. The smaller baskets are almost not visible with the naked eye but create a beautiful fractal look. Then, you loupe the pattern and see its intricacies. I feel it’s a pattern George Daniels would appreciate because he didn't like distracting patterns but was a fan of classic simplicity and elegance.”

A discussion of engine turning would not be complete without mentioning the one man to work with George Daniels, Roger Smith. Smith’s mastery of engine turning is perhaps best displayed in “The Great Britain”, a unique piece commissioned by the GREAT Britain campaign, a government effort to celebrate British artisanship. Every component of the watch is completely handmade by Smith, including the dial, which renders the Union Jack entirely in guilloché, with each of the flag’s contrasting colours utilizing a different engine turning pattern.

To create The Great Britain’s dial, Smith explained to Phillips that it took about three months, requiring the cutting of 34 individual pieces of silver and engine turning each before soldering them together in the pattern of the Union Jack. As Daniels bequeathed his workshop to Smith, his protégé, Smith often uses Daniels’ engine turning lathe for all of his dial work.

“The traditional approach to dial-making is very important to the way I build my watches, and the engine turning is a major part of that. It gives us our identity,” Smith said.

The basket weave on Smith's Grand Date Flying Tourbillon.

While modern independent watchmakers like Smith, Shapiro, and Voutilainen continue to practice the craft, it is also closely associated with vintage watches. Not only with Breguet or Vacheron Constantin, as Shapiro mentions, but also with Patek Philippe.

Because of the difficulty in execution, guilloché was often reserved for Patek’s most superlative watches. In vintage Patek Philippe, this means the World Timer. Even among World Timers, guilloché dials are rare; for example, in the highly-desirable vintage World Timer reference 2523, only four guilloché dials can be found in pink gold cases, one of which resides in the Patek Philippe museum. When one appears on the market, as happened in 2020 at Phillips Geneva XII, it is a cause for celebration. That example sold for $5.5 million, illustrating how the market continues to value engine turning in vintage timepieces just as much as the pieces executed by modern artisans.

For those interested in learning more about engine turning, Josh Shapiro’s HSNY lecture, The Secrets of Horological Engine Turning, and Roger Smith’s series explaining the technique are both highly recommended.

Frosting

Much like engine turning, frosting is another dial finishing technique that can be traced back to Abraham-Louis Breguet. In fact, you’ll also often see it referred to as “Breguet frosting”. Traditionally, Breguet would use a pure silver blank to craft dials from (if he wanted a gold dial, he would use a pure gold blank, never gold plated, as is the modern Breguet practice).

Silver contains impurities, so frosting is a method that removes those impurities from the metal. With Breguet’s traditional method, the silver is first heated up, causing the impurities to rise to the surface, and turning the metal black. The dial is then treated with acid, which burns off these impurities, and after a few rounds of burning and applying acid, only a slice of pure silver remains. The result is a pristine, silvery-white surface reminiscent of winter frost.

This technique can be observed in Breguet’s antique pocket watches, where Breguet would treat the silver blank to remove its impurities before proceeding with his signature engine turning. The technique was also practical, serving as a seal to help prevent oxidation of the dial.

The acid frosting technique is not seen very often today, more often a wire brush is used, as by MB&F in their limited edition LM101 'Frost'.

This method of using acid to “frost” a dial is rarely used in modern watchmaking, as the acid is dangerous and alternative techniques have been developed over the centuries. However, it is still employed by modern watchmakers who place an emphasis on traditional techniques, namely practitioners like Smith and Shapiro.

An alternative modern frosting technique used by watchmakers enlists a wire brush to create a similar aesthetic effect. The wire brushing is completed by hand to give the dial a similar frosting that is still hand-finished, without the watchmaker exposing themselves to harmful chemicals. Instead of chemically creating the frosting effect, as Breguet’s traditional finition en grenaillage did, this modern technique physically creates it by compressing and brushing the dial’s surface. Like other hand finishing techniques, this requires extensive time and skill to create a uniform appearance.

The hand-finished nature of this wire brushing technique sets it apart from inexpensive bead blasting techniques that might be used by brands employing mass production to imitate a frosted aesthetic. However, these machine-applied techniques can produce a frosting that appears too uniform, devoid of the character that defines true hand-finished frosting.

This hand wire brushing technique can be observed in the MB&F Legacy Machine LM 101 “Frost”, a limited edition release totalling just 51 pieces. What’s more, it was revealed on the brand’s tenth anniversary, and marked their first use of yellow gold. Given how rarely any sort of hand-finished frosting is seen in modern watchmaking, it was a true legacy statement from Max Büsser and Friends (in this instance, artisan Jose Labarga was called on to complete the dial frosting). In the case of the LM 101, the dial also serves as the main plate of the movement, a sliver of gold finished to perfection serving as a focal point of the timepiece.

Hand Hammering

Hand hammering is currently most famously used by AkriviA and its talented young watchmaker, Rexhep Rexhepi, and his team. AkriviA have employed the technique on several of its AK series timepieces, including the AK-02 and AK-06, as well as the piece unique Chronomètre Contemporain for Only Watch 2019.

A blank dial for the AK-02 having its pitted finish applied, courtesy of AkriviA.

This method of dial finishing requires only a hammer, a stake, and an extremely skilled hand. The watchmaker taps the stake hundreds of times into the dial to create a stunningly textured surface. The beauty of the technique is that because it is painstakingly completed by one watchmaker, it carries a sort of “signature” in which the irregularities of the spacing and size of the hammering are unique to the craftsman that made it. While AkriviA have perfected the technique, there is a randomness that cannot be truly eliminated because it is still a hand-finished, manual technique. This human element of certain finishing techniques is what makes them so widely appreciated, the eventual custodian of the watch able to discern the hundreds of hours of labour that went into finishing every component of the timepiece.

The finished result, as seen on an AkriviA AK-05 tourbillon.

Interestingly, Glasgow-based anOrdain has recently pioneered this dial finishing technique at a lower price point, introducing hammering to its already celebrated enamel dials.

“The idea behind hammering is to create a finish which reflects light in different directions so when you move the piece around, the light plays beautifully off the surface. It's a similar idea to more traditional techniques of engraving or using a rose engine lathe under enamel,” anOrdain founder Lewis Heath explained to us.

Much in the same way that Breguet took inspiration for his engine turning from ornamental and decorative objects of all types — not just watches — Heath points out that some of anOrdain’s hammering techniques are more akin to jewellery than watchmaking.

“The techniques are common to jewellery...our team all studied and worked in that field before apprenticing in enamel dial making,” he said.

To give an idea of the patience needed for this technique: anOrdain’s Model 2 uses a subtly domed dial to create a gradient effect in the enamel finishing. The “dome” is slight, with the high point just 0.2 millimetres above the low point of the dial. This means the hammering is executed nearly at the micron level, with the artisan fashioning tiny dents into a slice of silver no thicker than the average fingernail.

A pitted dial from Scottish makers anOrdain.

When asked how anOrdain has managed to keep its trademark affordable pricing, even while employing time-intensive techniques such as hammering, Heath emphasized the importance of investing in internal production. Much in the same way that Shapiro mentioned the importance of machinery in executing engine turning, so too has anOrdain invested in workshops, machinery, and skilled artisans to execute its dials.

Tapisserie

While Audemars Piguet’s tapisserie dials are rooted in the tradition of engine turning, the brand’s modern workshop uses a slightly different technique to achieve the instantly recognizable pattern on its Royal Oak dials.

Audemars Piguet uses a brocading machine, a tool that maintains a hand-made element to the dial-making process, but allows higher production than the entirely manual methods used by artisans like Smith and Shapiro. Unlike a traditional rose engine lathe, a brocading machine has a motor, meaning it can carve a pattern into a dial more autonomously. While a rose engine machine relies entirely on human touch to make its cuts, a brocading machine’s motor ensures the dial is cut in a precise, repeatable fashion.

Two of the more rare colours that you'll find in the iconic tapisserie.

Straddling the line between traditional, entirely handmade designs but yet not quite being a modern automated process, this machine uses a pantograph-like system to engrave the tapisserie pattern into a dial blank. On one side of the pantograph sits a large medallion replica of the Royal Oak’s tapisserie pattern; the machine essentially traces this design, reducing it in size and engraving it onto the dial.

This method is a substantial step above the stamping or automated CNC machining many modern brands might use to imitate the intensive, manual process of engine turning. As one might expect, the CNC process involves a type of 3-D printing with computer generated models and programming involved, turning the dials into instruments of precision, but lacking the human touch that we have explored and celebrated so far.

Finishing Thoughts

Equal parts art, science, and engineering, dial finishing techniques have evolved since the days of Breguet alongside the advancement of those disciplines. However, in their purest form, these techniques remain recognizable across generations, with modern artisans like Josh Shapiro and Roger Smith still drawing on the knowledge of Breguet, both relying on it and building upon it in equal measure.

The dial contains centuries of culture, stories, and secrets, all packed in a wafer of metal that measures less than one millimeter thick. It’s what has inspired artisans of haute horology like Smith and Shapiro to carry on the practice of engine turning, or Rexhepi to take a hammer to Akrivia’s dials. It has also inspired the workshops of anOrdain to challenge conventional methods and find ways for more collectors to enjoy these finishing techniques on their wrists.

It is this sense of wonder that continues to capture both artisans and collectors, eager to understand and advance the art and the science, ensuring these techniques of profound skill and engineering survive for centuries to come.

We would like to thank all of those who shared with us their time and knowledge on dial finishing, including Josh Shapiro and Lewis Heath.