Watch In Need of Service

Podcast How Watches Work E4 – Servicing Mechanical Movements

Our fourth ‘How Watches Work’ podcast is on watch servicing – what it entails and why it is needed. Allen is gunning for vintage watch dealers that advertise their wares as ‘freshly serviced’ while David explains the how to know when watch needs service and what to expect. Watch service is a deep subject and this first podcast on the subject is just the tip of the iceberg.

Why and When is Service Necessary?

The simple reason for performing a regular watch service is to replace the lubricants within the watch. Moving parts, whether they are metal on metal or metal on jewel, need the correct lubrication to minimize wear and maintain the movement’s performance. However, before lubricating the various pivots and jewels within a watch movement, the movement must be thoroughly cleaned to remove the old lubricant. It must also be fully disassembled during the service to ensure that the watch is clean of old oils while providing access to the internal components that need lubricantation.

Disassembled Watch Movement
Disassembled watch movement ready for cleaning

Lubricants are needed inside the watch to keep moving parts physically separated to minimize friction and avoid premature ware. As we have mentioned before, friction is the enemy of precise mechanical timekeeping. As lubricants age they degrade due to oxidation, mechanical wear and heat. In the past, old organic lubricants would gum up movements as they broke down, turning from slippery liquids into sticky messes. Back in those days, you received a clear indication that your watch needed service when it stopped running completely. These days, watch oils are synthetic and while they are more stable and perform better than the oils of old when new, they can evaporate and leave the watch seemingly running more or less fine without lubrication.

Therefore, it is vital to know when a watch needs service because running with little or no lubricant will rapidly wear out the internal components. So, how can one tell if a watch needs service or has been serviced? The simplest indicator is the amplitude of the movement which is described in more detail in our article on timegrapher results. In short, amplitude is the range of rotation of the balance wheel as shown in the image below. It is an excellent indicator of how much friction is within the gear train of wheels between the mainspring and the escapement. Low amplitude, where the balance wheel does not swing far in each direction, likely means there is high friction within the movement and service is required. Without a timegrapher or a report of its results, it is notoriously difficult to tell if a newly sold watch has really been serviced. Hence Allen’s quest to make all dealers provide photographic evidence to back up their ‘recently serviced’ claims.

Balance Wheel Amplitude

Photographic proof of service and restoration are commonplace in vintage car circles. Not only does the photographic record confirm what was done to the car, when and how, it establishes provenance as part of the car’s history for the next owner. Surely, this could also apply to watches. When faced between two identical watches to consider, one with a history file and one without, both David and Allen agree that the watch with history would normally be the watch to buy. Not only does the added documentation add to the user experience, such records increase the value of the watch. Unfortunately, watch buyers do not yet demand such levels of documentation from their sellers.

Watch buyers do not yet demand automotive-levels of service evidence or record-keeping

Many watch owners don’t know what to expect from a watchmaker when it comes to service – oftentimes simply trusting the watchmaker to do the right thing. And in most cases, the watchmaker, being a professional, does do the right thing and performs the required service. However, by not providing clear assessments, clear communication and clear evidence of the service, the impression that watch service is a secretive black art are perpetuated. This perpetuation of trust without evidence is what enables watch dealers to get away with claiming a watch was recently serviced without any clear statement of what was really done.

Watch In Need of Service
A recent vintage purchase that claimed to be recently serviced. Not with that amplitude it was not.

Finally, Allen and David propose a minimum standard for service documentation that includes an informative initial assessment, photographs of the movement disassembled and timegrapher evidence of performance after service.

Further Reading