SWISSWATCHES PATEK PHILIPPE

The Servicing

of a Patek Philippe

Aquanaut Chronograph Ref. 5968A

What happens during the servicing of a high-end chronograph?

Why should a watch be serviced at all?

If you wait until a watch stops running or starts displaying a noticeably inaccurate time, damage to the movement has already occurred. This is because oils and greases, even modern synthetic lubricants, cannot stay in place indefinitely. Over time, they degrade or migrate, allowing mechanical wear to damage movement components.

After a decade of operation, the ruby pallet stone of the Aquanaut chronograph will have arrested the escape wheel more than 1.26 billion times, a quiet endurance that ultimately calls for renewed lubrication.

Patek Philippe Aquanaut Chronograph 5968A

Patek Philippe Nautilus 5711

Patek Philippe Nautilus 5711

The servicing
of a Patek Philippe watch

Find out how servicing at Patek Philippe is usually handled and why high-quality timepieces should always be serviced by an authorised retailer.

Where can I have my Patek Philippe serviced?

Your authorised Patek Philippe retailer in Germany

Augsburg

Hörl

Berlin(2)

Bucherer – Patek Philippe Boutique

Wempe

Dortmund

Rüschenbeck

Düsseldorf(2)

Rüschenbeck – Patek Philippe Boutique

Blome Uhren

Frankfurt(2)

Wempe – Patek Philippe Boutique

Wempe

Hamburg(2)

Wempe – Patek Philippe Boutique

Mahlberg

Keitum / Sylt

Krause – Patek Philippe Boutique

Köln(2)

Gadebusch

Wempe

Mülheim an der Ruhr

Laerbusch

München(2)

Bucherer – Patek Philippe Boutique

Wempe

Münster

Oeding-Erdel

Oberstaufen

Hollfelder

Stuttgart

Kutter

Ulm

Scheuble

Wiesbaden

Oberleitner

Kitzbühel

Rüschenbeck

Servicing a Patek Philippe Aquanaut Chronograph Ref. 5968A

With a chronograph such as the Aquanaut Ref. 5968A, servicing involves a number of additional and particularly intricate procedures. We examined the key stages of this process first-hand at the Patek Philippe Service Centre in Munich.

1. Removing the central chronograph seconds hand

High-performance equipment for the chronograph centre seconds hand

After removing the movement and dial from the case, the watchmaker uses a special tool to lift off the central chronograph seconds hand. The centre seconds hand cannot be lifted in the same way as the other hands, which are protected by a foil and removed with two hand levers, because doing so could otherwise damage the coupling beneath the chronograph centre wheel.

Disassembled into its individual components

1. A special tool is used to unscrew the screw-down caseback.

1. The fully threaded caseback is unscrewed using a special tool.

2. Then the caseback can be removed.

2. The caseback can then be removed.

3. The watchmaker removes the automatic rotor so it won’t be damaged.

3. The watchmaker removes the automatic rotor to prevent any damage.

4. After pulling the crown, he can remove the movement with dial from the case.

4. After pulling out the crown, the movement with the dial can be removed from the case.

5. A special device is used to lift off the seconds hand.

5. A special device is used to lift off the seconds hand.

6. The central chronograph seconds hand is slid into the device’s holder.

6. The chronograph seconds hand is inserted into the holder of the device.

7. Then the watchmaker operates a lever and the device lifts off the hand.

7. The watchmaker then operates a lever, allowing the device to lift the hand safely.

Disassembled into its individual components

Stripped down to its individual components

The dial can now be removed, allowing the dismantling of the date mechanism beneath it. The watchmaker then takes apart all the movement components on the reverse side, step by step, including the automatic bridge, mainspring barrel, balance cock, balance, chronograph mechanism, wheel train, and motion works. Ultimately, only the mainplate with a few jewels remains.

The finely decorated movement awaits disassembly. csharp Code kopieren

The intricate movement is ready for disassembly.

1. First, the watchmaker loosens the screw of the balance cock. nginx Code kopieren

1. First, the watchmaker loosens the screw securing the balance cock.

2. The seconds wheel is removed. markdown Code kopieren

2. The seconds wheel is removed.

3. The barrel bridge also has to come off. csharp Code kopieren

3. The barrel bridge is subsequently detached.

4. The column wheel and the rest of the chronograph mechanism are removed. pgsql Code kopieren

4. The column wheel and the remaining parts of the chronograph mechanism are removed.

5. In the end, only the mainplate with a few jewels remains. sql Code kopieren

5. Finally, only the mainplate with a few jewels remains.

6. The parts are then placed in a basket and cleaned in an ultrasonic machine. sql Code kopieren

6. The components are then placed in a mesh basket and cleaned by an ultrasonic machine.

Chronograph centre wheel: coupling and reset

The chronograph centre wheel is at the heart of the CH 28-520 C chronograph calibre because it carries the multi-part vertical clutch that controls the rotation of the central chronograph seconds hand. Mounted on the same arbor is the heart cam, which works with the reset hammer to return the chronograph seconds hand to zero. The watchmaker removes and dismantles the chronograph centre wheel. As with all components, it is inspected for damage, with any debris being removed.

The tiny chronograph center wheel fulfills several functions. css Code kopieren

The tiny chronograph centre wheel performs several key functions.

1. The chronograph center wheel—the heart of the chronograph caliber. bash Code kopieren

1. The chronograph center wheel — the heart of the chronograph movement.

2. The chronograph center wheel consists of an arbor onto which the components are stacked in layers. markdown Code kopieren

2. The chrono centre wheel consists of an axle on which the components are arranged in layers.

3. A special tool is used to dismantle the chronograph center wheel. pgsql Code kopieren

3. A special tool is used to dismantle the chronograph centre wheel.

4. It loosens all the parts seated on the arbor. css Code kopieren

4. This tool loosens all parts mounted on the axle.

5. Only the reset heart cam and the pinion are fixed to the arbor. pgsql Code kopieren

5. Only the zero reset wheel and the drive wheel are firmly connected to the shaft.

6. The clutch (left) and the reset heart cam with the levers that actuate it. pgsql Code kopieren

6. The clutch (on the left) and the zero-reset heart, along with the levers that operate it.

7. The clutch consists of a bushing, spring, coupling disc, and clutch wheel. sql Code kopieren

7. The clutch assembly comprises a bushing, spring, intermediate disc, and clutch wheel.

Assembling the heart with the clutch

Once all the movement parts have been returned from the ultrasonic cleaning machine, the chronograph centre wheel can be reassembled. Patek Philippe provides a special assembly tool for this purpose: a brass jig. It holds the shaft with the zero-reset heart and pinion, the three-armed spring, the connecting disc and the clutch wheel together until a bushing is pressed on. This bushing holds the system together at the correct distance, enabling the clutch pliers to open the clutch later via the sloping surface of the connecting disc. During assembly, each component is checked and any contaminants, such as dust particles, are removed using Rodico modelling clay. The functional surfaces are then lubricated using an oil dispenser.

Assembling the clutch with heart cam css Code kopieren

1. The parts return cleaned from the ultrasonic bath. csharp Code kopieren

1. The components are cleaned in an ultrasonic bath.

2. In the assembly tool, everything is threaded back onto the arbor—first the spring. csharp Code kopieren

2. The components are reassembled onto the shaft in the assembly tool, with the spring fitted first.

3. Then the coupling disc. vbnet Code kopieren

3. The connecting disc follows.

4. The clutch wheel is added. markdown Code kopieren

4. The coupling wheel is added.

5. Finally, a tiny bushing is pressed on. csharp Code kopieren

5. Finally, a tiny bushing is pressed on.

6. The watchmaker checks that the clutch components move freely and that the spacing is correct. vbnet Code kopieren

6. The watchmaker ensures that the coupling components operate smoothly and that the spacing is correct.

Adjusting springs and levers

The watchmaker uses a spring gauge, a specialised metal tool, to check whether any of the chronograph springs are fatigued or bent. Any faulty springs are replaced, while others are carefully straightened with tweezers. Next, the chronograph mechanism, including the levers and coupling wheel, is reassembled in a time-consuming process due to the numerous lubrication points. The heights of the springs are also adjusted with great precision.

Straightening springs and levers css Code kopieren

The spring template has different slots. nginx Code kopieren

The spring jig has different recesses.

Each spring is fixed in the appropriate slot. cpp Code kopieren

Each spring is secured in its corresponding recess.

Using tweezers, the watchmaker can shape it back into the correct form. csharp Code kopieren

The watchmaker can use the tweezers to shape it correctly.

The spring template is made from a solid metal block. powershell Code kopieren

The spring template consists of a solid metal block.

1. When assembling the chronograph, numerous points must be lubricated. pgsql Code kopieren

1. Numerous components must be lubricated when assembling the chronograph.

2. The watchmaker removes the cleaned parts from the basket. less Code kopieren

2. The watchmaker removes the cleaned parts from the sieve.

3. Lubricants are available in different viscosities. csharp Code kopieren

3. Lubricants are available in different viscosities.

4. All functional surfaces of the column wheel are lubricated. arduino Code kopieren

4. All functional surfaces of the column wheel are lubricated.

5. The watchmaker reassembles all parts of the chronograph. sql Code kopieren

5. The watchmaker reassembles all parts of the chronograph.

Everything comes together

Next, the gear train, mainspring barrel, bridges, and automatic winding mechanism are installed. The watchmaker assembles the escapement and balance wheel with its tiny shock absorber. The jewel bearings and ruby pallet stones are carefully lubricated in the process. Using a timing machine, the rate, beat symmetry, and positional variation are checked and adjusted, and the watch is regulated

Movement assembly: bridges

1. So far, only the chronograph mechanism is assembled.

1. So far, only the chronograph mechanism has been assembled.

2. Insert the mainspring barrel as the energy store.

2. The mainspring barrel is used to store energy.

3. The barrel bridge secures the mainspring barrel.

3. The barrel bridge secures the mainspring barrel in place.

4. The bridges are carefully screwed down.

4. The watchmaker carefully screws the bridges into place.

1. Jeweling tools are used to adjust the endshake of the wheel train.

1. The height of the wheels is adjusted using the stone setting tools.

2. The shock protection with its spring and cap jewel is tiny.

2. The shock protection with its spring and cap stone is tiny.

3. The watchmaker assembles the shock protection.

3. The watchmaker assembles the shock protection.

4. The shock protection safeguards the delicate balance staff.

4. The shock protection protects the sensitive balance staff.

5. And it is installed on both sides.

5. And is mounted on both sides.

Zero reset of the chronograph hands

To test the chronograph reset, the movement is placed in a special jig with pushers, onto which a test bridge is mounted. The central chronograph seconds hand and the chronograph minutes hand are then fitted, and the chronograph is started, stopped and slowly reset. The interaction between the reset hammer and the heart cams must function perfectly. The instantaneous date change is also checked.

The movement holder allows the reset pusher to be operated slowly.

The movement holder allows the reset pusher to be actuated slowly.

With the test bridge installed, the watchmaker checks correct reset function.

With the test bridge fitted, the watchmaker checks correct reset behaviour.

Both chronograph hands must reliably return to their zero position.

Both chronograph hands must return reliably to their zero position.

Mounting the Chronograph Seconds Hand

Once the movement has been regulated, the dial mounted, and the hour and minute hands correctly aligned for the date jump, the watchmaker can fit the chronograph hands. The central seconds hand requires special attention due to the significant forces acting on it during resetting, its length, and its slender arbor. If it were fitted in the same way as the other hands, it could eventually come loose during operation. To prevent this, the steel hand is pressed into place using a Forcetest device with a predefined force. For this reason, it must be replaced at every service, and the hand lining is carefully opened with a tiny awl so that the hand can be seated about one third onto the arbor before being firmly pressed into position.

Installing the central chronograph seconds hand

1. Dial and hands are ready for installation.

1. The dial and hands are laid out, ready for installation.

2. The watchmaker mounts the dial onto the movement.

2. The watchmaker fits the dial to the movement.

3. The hands are fitted.

3. The hands are mounted.

4. Using a tiny awl, the watchmaker reams the collet of the central chronograph seconds hand.

4. Using a tiny awl, the watchmaker slightly opens up the lining of the chronograph seconds hand.

5. The hand must fit about one third of the way onto its arbor.

5. The hand must fit around one third of the way onto its arbor.

6. Then it is pressed on with the Forcetest device using a specified force.

6. It is then pressed into place with a Forcetest device using a predefined force.

Patek Philippe Aquanaut function and precision test

Only once appearance, rate, and function are all perfect is the watch returned to its owner.

Function and precision test

Once the overhauled movement has been re-cased in the refinished case, it enters the quality-control phase, which alone takes nine days. During this period, the winding efficiency of the automatic movement is tested on a watch winder, the specified power reserve is verified, and rate accuracy is checked in different positions as well as after 0 and 24 hours. To meet the stringent requirements of the Patek Philippe Seal, daily rate deviation must fall within –1 to +2 seconds per day.

In total, a watchmaker spends around ten hours servicing the Aquanaut Chronograph movement itself. Additional time is required to restore the case and clasp, as well as to carry out several days of tests on winding, power reserve, and accuracy. Once water resistance and aesthetic excellence have been confirmed, the Patek Philippe can be returned to its owner. For them, it is a delightful moment: the movement is effectively as good as new – meticulously cleaned, perfectly lubricated and adjusted, and precisely regulated.

Patek Philippe Aquanaut function and precision test

A special device tests the water resistance.

A specialised device tests the watch’s water resistance.

Function test: Are the pushers as smooth and light to operate as desired?

Functional test: do the pushers operate as smoothly as intended?

The winding simulator tests the winding efficiency of the automatic movement.

A watch winder checks the winding efficiency of the automatic movement.

The timegrapher measures rate accuracy in different positions.

The timegrapher measures rate accuracy in different positions.

Only when the appearance, rate, and function are perfect is the watch delivered back to the customer.

How often should the watch be serviced?

Patek Philippe recommends servicing its watches every eight to ten years. This helps ensure lasting rate accuracy and keeps the movement sufficiently lubricated to prevent excessive wear.

How often should the watch be serviced?

How long does servicing take?

Clients should expect a processing time of ten weeks for automatic chronographs before they receive their watches back. Quality control alone accounts for nine days of this process.

How long does the service take?

What qualifications does a watchmaker need to service the Aquanaut Chronograph?

After completing a three-year apprenticeship as a watchmaker, new Patek Philippe employees attend a five-week course in Geneva, qualifying them to service three-hand watches. Only after gaining at least three years of professional experience can they undertake a further six-week course in Geneva, which qualifies them to work on more complex timepieces, such as those with annual calendars and world timers. After a further three years, watchmakers can undertake a three-week specialist course covering Grand Complications like perpetual calendars and hand-wound or automatic chronographs. In total, it takes almost ten years and the successful completion of several training programmes before a watchmaker is authorised to work on chronographs.

Only after ten years of experience and several training courses is a watchmaker allowed to work on a Patek Philippe chronograph.

Only after ten years of experience and several training courses is a watchmaker allowed to work on a Patek Philippe chronograph.

0

Would love your thoughts, please comment.x

()