At An age where powerful computer aided design machines can design any watch and where the whole industry is trying to go upscale, there is one major element which makes the difference : movement finish.
This is what truly differentiates haute horlogerie from the wannabes. I’m of course referring to the extremely time consuming manual finish (and not the machine finish found in the majority of movements) which can actually represent 1/3 of the price of a timepiece. It is the extreme care and attention given to the smallest details whether visible or not that makes the difference.
The goal of this article is not to detail exhaustively every single process of movement finish, but rather give an overall view on certain finishing techniques used at Vacheron Constantin.
You can click on the scans for a larger view and click on the films to play.
WHAT IS MOVEMENT FINISH?
Most often, a watch movement is made of brass, maillchort (German silver), steel or gold (or any mix thereof), in high horology these metals are milled (not stamped) to create the necessary components which are in a raw form. Movement finish rids these components of burrs and traces of machining but most of all; the different processes transform dull metal into an aesthetically pleasing and eye catching mechanism.
|baseplate in raw form ready to be finished|
It is important to note that each component which undergoes a finishing touch is systematically controlled to make sure that it has not been deformed in any way as even the slightest modification of form could be hazardous to the watch’s correct functioning.
|each component is placed under magnification for examination|
VACHERON CONSTANTIN’S FINISH AND MOVEMENT DECORATION ATELIERS
In a calm and reposing atmosphere overlooking a beautiful green park, Vacheron Constantin’s movement finish department team are hard at work. These skilful hands are not watchmakers but people who have had a special training on movement finish and decoration, called finisseurs (finishers). Says the head of this department at Vacheron Constantin: “unfortunately watchmaking schools no longer teach the kind of high grade finish we need”, therefore the brand has set up a special internal program which can take anywhere between 6 months to a year and a half to complete, depending on the type of finish the person is to work on. The objective, nevertheless, is for the members of the team to learn to do all types of finish, one of the most complex being bevelling of interior angles which takes 18 months of training!!
In the recent years Vacheron Constantin has taken an immense leap forward in terms of movement finish going from good to exceptional in just a few years. This applies also to the non visible and underdial parts. I asked a person working in the ateliers if it was not too frustrating spending so much time touching up parts and surfaces which the owner would never see and the answer was “yes it can be frustrating but knowing that the work is perfectly done and that the watchmaker who assembles the movement or the one who at a later date will take the movement apart for servicing will be pleased with what sees gives us great pride”!
Drawing is one of the very first steps in movement finish and an important process which determines the quality of the bevelling, as the quality of the latter depends greatly on the aesthetics of the former. Drawing is done on the flanks of plates and bridges to remove burrs and traces of machining giving the surface of the flanks a smooth appearance. The flank is smoothed using a file and then satin brushed with a diamond grinding head fitted on a motor called Microcut. The flank is rubbed lengthwise in order to form unidirectional longitudinal lines.
|drawing the flanks of a plate|
CHAMFERING or BEVELING (ANGLAGE)
Certainly one of the most complicated of finish methods, it is both time consuming and requests the most dexterous artisanship. Bevelling consists of eliminating the edges between the surface and the flanks forming a 45° angle. The edges of the flank are gently pressed down and then polished to give a very shiny aspect. The surface of the angle needs to be regular and smooth with a constant width and parallel edges. It is a very difficult process since if too much pressure is exerted the component will deform and if not enough the angle will not be sharp and clear.
There are different kinds of bevelling:
- Interior angles: where two bevels meet but must be made in a way that looks as if it is a continuing line, this is the finish which requires 18 months of training at VC!
- Exterior angles: the bevels meet at the exterior of the component and the corner must be sharp.
- Rounded angle: the angle follows a rounded pattern.
|Caliber 1400 A-Interior angle / B-Exterior angle / C- Rounded angle|
Two methods are used for bevelling, depending on the type and area bevelled:
* Files: used for interior bevelling as well as areas which can only be reached by a small file (ex in skeleton watches). It is interesting to note that the tools used are prepared inhouse by VC as to perfectly correspond to the desired aesthetics. The angles are created by using files of different sizes and grains or using abrasive pastes. The radiance is obtained by rubbing the surface with diamond paste covered pegwood or a specific rubber. This last step also gets rid of residues.
|work bench||different sized files||beveling|
* Grinding Wheels: used mainly for rounded and exterior bevels. Wooden and leather wheels on which abrasive paste has been applied are used. Each wheel has a different thickness, and is used depending on the size of the component or the type of bevelling. The finisher gently rubs the component against the rotating discs until the required result is obtained, then the component is polished using the leather wheal to obtain its sheen. The technique using the grinding wheel calls for extreme dexterity as material is removed and any mistake would be difficult to make up for.
Other than its aesthetics, believing also removes residual burrs and limits corrosion.
CIRCULAR GRAINING (PERLAGE)
Also called perlage due to its resemblance with a row of tiny pearls. Circular graining consists of applying a small overlapping circular pattern often on the non visible sections such as the top and base plates; however you can catch a glimpse of the circular grain pattern on the base plate behind the balance. Circular graining is obtained by using the flat end of a piece of pegwood on which emery paste has been applied or abrasive pads (between 1-3mm in diameter), the pad is fitted on a rotating head which the finisher presses on the surface of the bridge or plate to create the requested pattern. Done manually, the pattern must be perfectly linear on different rows. Believe it or not the calibre 1400 has 642 different circular grains of 3 different sizes!
|base plate ready for perlage||applying the pattern|
|same baseplate as above but with circular graining||side by side comparaison|
GENEVA WAVES (COTES DE GENEVE)
Geneva waves are arguably the most well-known form of finishing and are characterized by a series of arc-grained bars etched lightly onto bridges or plates, creating a wave-like effect.
Mainly used on the visible parts, it only has an aesthetic purpose and in no way should be applied to functional areas as it could adversely affect the functioning of the movement (since material is removed).
The stripes are applied using abrasive paper fixed onto a brass-cylinder which is pressed down, lightly, into contact with the polished surface and in a longitudinal motion will stripe the component. Each stripe should be perfectly even and parallel to the other.
The pressure exerted on the component is of primary importance, too much pressure and the surface will look rough and too little pressure and the stripes will lack relief. In the best forms of Geneva waves, the stripes over the whole movement should align perfectly
|the machine used for applying Geneva waves||the brass cylinder applying finish to the component|
|straight lines on cal 1400||circular lines on cal 2475 (dial side)|
BLACK POLISH (POLI NOIR)
Also called mirror polish. This finish derives its name from the black or grey shine, depending on the angle it is looked at, that the component radiates. In high horology it is often found on tourbillon bridges or repeater hammers, but Vacheron Constantin also uses black polish amongst others on its regulating indexes and hairspring stud covers.
Mirror polishing is an arduous process, only possible on steel, the component needs to be polished in a circular motion, on a zinc plate using diamond pastes of different grains (commencing with coarse and moving till fine grain).
Black polish is the highest level of polish achievable with no visible markings on the polished surface (even when examined under high magnification). The surface (which reflects light in only one direction), depending on the angle it is looked at, will appear to absorb all light, giving it a deep black appearance or reflect an intense amount of light, entirely undiffused when a light source shines directly upon it.
|index and stud cover||tourbillon bridge|
The plates and bridges have holes drilled in them but the drilling leaves burrs and irregularities which need to be removed. The holes’ sizes are first adjusted using a cylindrical cutting tool. Then sinks and countersinks are rounded using a diamond milling cutter. The jewelled countersinks often have the highest amount of polish as to give the red jewel an eye catching visual effect.
The different wheels are bevelled on their arms, upper and lower sides and with polished sinks. They also receive a sunray finish which consists of smoothing the wheel face with a sandpaper or an abrasive stick. The wheel is placed on a rotating machine and a stick or buff is gently applied on it as to give it a circular or sunray pattern.
As surprising as it may seem, something as relatively insignificant as screws play an extremely important role in high end watchmaking, as there is no way you can miss seeing them!
The most commonly used type of screws in high end movements is the flat head screw which can be highly polished and with its bevelled slot and rim has an excellent aesthetic appearance.
The screws are polished using abrasive papers or pastes. The slot heads and rims are also bevelled.
|screws holding the rotor|
BROUILLAGE (did not find an English translation)
Consists of eliminating all residues and burrs on the non visible surfaces of the components which have not received surface finish (ie: circular graining, Geneva waves…). It is done so by rubbing the component on a sheet of abrasive paper giving it a sand blasted mat look.
|the components are 1st firmly fixed on a support||then rubbed against an abrasive sheet|
|before (component on the botton) and after (component on top)|
TRUE UP or STRAIGHTEN (DRESSAGE)
Similar to “brouillage” but done on the visible surface of the component which has not received Geneva wave or circular grain finish. The component is rubbed against a sheet of abrasive paper to obtain straight grains in a perfectly linear manner. It is repeated in the same direction until any blemishes in the metal that are not in line with the desired grain are removed. This operation gives the component a sandblasted effect.
Aficionados are more and more attentive to the quality of finish but few (yours truly included) could possibly fathom the extreme complexity of a fine finish. Even though all the operations above can now be done by CNC machines the hand work, dexterity and time needed to truly bring life and brilliance to metal parts can only be done by caring hands.
No matter how technically advanced or well constructed a movement is, if the finish is sloppy or less than par the movement will not make the part. That’s why time is of little importance in Vacheron Cosntantin’s finish department, each finisher works at his or her pace making sure that even the tiniest component receives the utmost attention. Each person works on movement kits and needs to make sure that the finish applied to each component is consistent as not to have any discrepancies between parts once the movement is fully assembled.
To give you two examples of this, a plate for a skeleton watch can take over a day just to bevel, a tourbillon bridge requires over 11 hours of black polishing. In January, 100 caliber 1141 (manual wind chronograph movement) kits were delivered to the department for finish in and have remote chances of being completed by July! This is definitely one atelier which is not guided by turnovers and numbers but by perfection.
A dedication to perfection which lead independent maestri Kari Voutilainen and Philippe Dufour to respectively laud the finish of calibres 2475 and 1400 as being part of the top in today’s high end horology, and once such respected watchmakers, known for their superlative finish, speak as such then alea jacta est.