Vision versus reality in mechanical masterpieces

The ideal situation would be for a wristwatch to always display the exact time standard, which in Germany is specified by the Physikalisch-Technische Bundesanstalt with its atomic clocks. So far, no manufactory has achieved the ideal goal. A mechanical movement consists of an impressively large number of components that are meticulously coordinated with one another.

Despite the love of perfection, small irregularities cannot be avoided. This is especially true in the long term, because the best material quality does not rule out wear and tear or soiling. In addition, there are external influences that provoke watch defects. Although ambitious traditional brands invest a great deal of passion and know-how in optimizing rate deviation, the fact remains that anyone who loves mechanical timepieces must have a little tolerance.

Guide values – excellent, good and acceptable rate deviation per day

Beginners are usually spontaneously thrilled when the first self-winding mechanical luxury watch sits enthroned on their wrist. It’s like a miracle that the hands turn their rounds flawlessly without an external power supply, while you proudly gaze at the magnificent watch design. In times of radio-controlled watches and smartwatches, however, one detail is unusual: the time display is almost never exact. This is followed by the thought:

Is the rate deviation of my automatic watch normal?

If the daily irregularities are between -4 and +6 seconds daily, the Contrôle Officiel Suisse des Chronomètres pulls out its certificate. The name of the renowned institute reveals that the result is excellent. This is because portable timepieces may only be marketed as chronometers if they are exceptionally precise.

Ambitious watch manufacturers voluntarily raise the quality bar for their masterful collections. Omega, for example, opts for METAS certification, which defines 0 to +5 seconds as an acceptable rate deviation per day. One can be absolutely satisfied if the average values for the rate deviation are +/- 10 seconds. Since 86,400 seconds pass per day, the display is 99.9 percent correct. In general, there is no cause for concern for the time being, as long as a mechanical movement does not run more than half a minute too fast or slow every day.

Rate deviations – mostly normal, sometimes alarming

By chance, you meet a soulmate who has treated himself to the same masterpiece. While chatting, however, a difference is noticed: The interlocutor raves that he doesn’t notice any rate deviation. Their own specimen, on the other hand, exhausts the stated precision spectrum. Worries are unfounded at this moment. The chance acquaintance is a lucky man, and the accuracy of his own model is still impressive. It is typical for craftsmanship that minimal differences arise in the manufacture even when all manufacturing steps are meticulously executed.

It is just as normal for a mechanical movement to run somewhat unevenly on debut. These “start-up difficulties” can be caused, for example, by the fact that the lubricant has not yet caressed all the components inside. If the problem doesn’t go away, the movement may need to be readjusted. These are simple standard adjustments, which should definitely be done by the manufacturer or authorized watchmakers. After all, the opening of exclusive automatic watches by unauthorized persons can lead to the loss of warranty.

Inaccuracies within the certified tolerance spectrum are okay. The same applies if the rate deviation of your everyday companion increases somewhat over the years. One should become attentive if mechanical wristwatches suddenly and clearly deviate from the usual accuracy. Today exact, tomorrow too slow, the day after tomorrow hasty: Enormous fluctuations should also be kept in mind. If the rate stability does not return, a check-up with an expert is recommended.

Want more accuracy? A little love helps!

Watch manufacturers consider all factors of rate accuracy in order to counteract deviations as best as possible. However, as soon as a masterpiece leaves the house, the owner’s cooperation is required. The way the watch is worn and stored influences the rate deviation just as much as the general condition of the watch. The self-winding mechanism ensures that energy is always replenished when the watch is worn. Nevertheless, some experts advise a complete manual winding at regular intervals. If a timepiece is left lying around for a longer period of time, it comes to a standstill, which is not to the liking of the automatic movement. For valuable collector’s items, specialist stores such as Uhrinstinkt therefore offer watch winders.

Automatic watches often run faster in high temperatures and slower in cold. Watch collections should therefore be treated to a constant room climate. A favorite piece should only be exposed to extreme temperatures if it has been explicitly designed for this purpose. The same applies to pronounced vibrations, shocks or moisture.

Realistic Detox Treatments and On-Time Revisions

Magnetic fields are among the significant factors in accuracy. Nowadays, however, they are omnipresent and emanate, for example, from notebooks, smartphones, induction stoves or pocket fasteners. If you notice a deviation, it may be time to demagnetize your watch – in a specialist store or with your own device. The problem is significantly reduced with modern luxury watches that are designed to be anti-magnetic. This feature is indispensable when magnetic influences characterize personal occupation or leisure activities.

The best building components wear out. Oils can gum up. Fine dust manages to creep through even the tightest case. In short, anyone who wants to enjoy a functioning automatic watch in the long term should adhere to the manufacturer’s recommended inspection intervals.

Quartz watch vs. automatic watch – why not both?

There are many professional or private reasons for attaching great importance to low rate deviation. It’s just as understandable if you don’t want to deal with influencing factors and watch care all the time. Who feels addressed, may flirt for the everyday life with a quartz watch. With good models, the annual deviation amounts to 60 seconds, while the battery lasts up to three years.

Frédérique Constant’s Classics Quartz collection suits business suits as well as casual wear. With its clear time display, date window and cosmopolitan GMT function, it fulfills all common needs at the same time. The icing on the cake: The brand doesn’t expect a big investment for it, leaving more budget for the mechanical collector’s item.

Will it experience adventures rather than elegant moments? Then this tip is valuable: COSC certification certifies excellent rate deviation under normal conditions. Extreme weather, movements, shocks or magnetic fields: Experienced manufacturers take into account in their own tests that expedition watches or sports chronographs, for example, are exposed to greater stress.

In this way, they ensure that, despite special influences, the accuracy is convincing and the functionality is preserved. That’s why it’s worth focusing on collections that have been designed for the intended use and meet all personal quality requirements.

Der Beitrag What rate deviation is normal for automatic watches? erschien zuerst auf Uhrinstinkt Magazine.

In 729 million years, it will still run precisely to the second: The NPL-CsF2 atomic clock in London. Neither quartz watches nor mechanical timekeepers can match this precision. But which brands do you have to visit to find the most accurate mechanical watches? From Breitling to Zenith, our magazine shows you the most accurate automatic movements in the industry and explains why luck also plays a role in the purchase.

Gear deviation: measurement of precision

To determine how accurate a wristwatch is, the daily deviation from perfect time is measured. If this were zero seconds, we could speak of perfect precision and the timepiece would be a serious competitor for the NPL-CsF2 atomic clock. In reality, however, this is never the case: even quartz clocks, which are known for their exceptional accuracy, move away from atomic time by a few seconds per year. An exception are radio-controlled clocks, which do not generate permanent rate deviations due to their regular synchronization with international time signal transmitters. In the mechanical universe, however, different standards apply: top-of-the-range watches stay within the window of -2/+2 seconds daily, but even five seconds difference would be a reasonable value. In the entry-level range of mechanical watches, even 20 seconds of rate deviation per day can be tolerated. Of course, these are not the most accurate watches in the industry.

Rolex: From Datejust 41 to Submariner the strictest criteria

These days, many watch enthusiasts question whether the prices of new Rolex watches are still justified. However, there is one thing that cannot be debated: The rigorous precision standards of the traditional Geneva brand. While the COSC still allows deviations of -4/+6 seconds a day to pass in its testing procedures, watches with the five-pointed crown in their latest generation of calibers must meet -2/+2 second accuracy. The Rolex Datejust 41 was one of the first watches to enjoy the pleasure of what is currently Rolex’s most accurate self-winding 3235 movement: Thanks to a new barrel, the patented Chronergy escapement with Parachrom hairspring and other technical details, the manufacture movement is not only extremely precise, but also has a considerable power reserve of 70 hours.

Breitling, Tag Heuer and Co.: Many brands rely on COSC

Compliance with such extremely precise standards of accuracy involves a great deal of technical effort and is difficult to achieve, especially in lower price ranges. Many manufacturers from entry-level to high-end therefore rely on the standardized, globally recognized testing procedure of the official Swiss chronometer testing body COSC. Even Rolex has its watches issued the coveted certificate and additionally applies its more stringent in-house criteria. Consequently, by no means all COSC-certified timepieces are equally precise; if you’re looking for the most accurate watches, Breitling, for example, is the place to go. In addition to the in-house B01 automatic movement, the B20, developed in cooperation with Tudor and used in the Breitling Superocean Heritage II, also stands out for its accurate rate. Durable and technically balanced, it is respected throughout the industry, offering 70 hours of endurance and meeting COSC guidelines with flying colors.

In addition to the Breitling Superocean Heritage II, the TAG Heuer Carrera Caliber 36 deserves a special mention: To build the automatic movement, the Swiss manufacturer used the technical know-how of LVMH’s sister company Zenith, which has one of the most precise and best movements of all time in its program with the El Primero. Its high frequency of five hertz, which plays into the cards of a precise gait, is adopted by the TAG Heuer Carrera Caliber 36 and paired with a 50-hour power reserve. If you’re looking for the most accurate watches at relatively affordable prices, you’ve come to the right place.

Omega: METAS certificate for highest accuracy

More stringent in comparison to the COSC is the precision measurement of the Swiss Federal Institute of Metrology (METAS), which has gained a high profile primarily through Omega, but is in principle open to all brands. In order to identify the most accurate mechanical watches, METAS, in contrast to the COSC, carries out precision measurement in six instead of five layers, tests entire watches instead of pure movements, and attaches importance to a high magnetic field resistance of 15,000 gauss. Eight different tests must be completed under the influence of this magnetic field, and the watches must not deviate more than 5 seconds a day from perfect time.

A prime example of the performance of METAS movements is the caliber 8800 in the Omega Planet Ocean 600M: its free sprung balance with silicon hairspring ensures exceptional longevity and precision, while the rhodium-plated finish with Côtes de Genève arabesques is a highlight for the eye. Not to be missed is the in-house Co-Axial escapement. Despite 600 meters of water resistance, the Omega Planet Ocean manages to reveal its precise beauty through a glass back. 55 hours of power reserve is a decent value.

Zenith El Primero: King of precise chronograph movements

Zenith comes closer to the accuracy of radio-controlled watches than any other mechanical brand. Although the “normal” El Primero calibers are already extremely precise with their beat frequency of five hertz, the Defy collection breaks records with the Inventor: the technical masterpiece achieves an incredible 18 hertz (129,600 vibrations per hour) thanks to the in-house, patented Zenith Oscillator in caliber 9100, which replaces around 30 components of a standard movement in one piece. The precision of this Zenith El Primero is in heavenly spheres: A maximum of 0.3 seconds of rate deviation per day sets new standards for mechanical watches.

Variance: Why precision is a matter of luck

A glance at the precision standards of COSC, METAS and others reveals that the accuracy of mechanical watches can only ever be guaranteed within a certain range, such as -5/+5 seconds of daily rate deviation. In plain language, this means that every watch ticks a little differently, which is due not only to tiny mechanical differences, but also to the smallest differences in regulation. You have to keep in mind that one day comprises 86,400 seconds; if two watches differ by five seconds, the continuity of production is still impressive. Whether you as a buyer get a specimen close to the zero-second limit or the five-second maximum deviation is a matter of luck.

Junghans: accurate radio-controlled watches for absolute precision

Whether it’s Junghans Force or Junghans Spektrum, anyone looking for perfect precision synchronized with atomic time signal transmitters should set their sights on the radio-controlled collections from the traditional Black Forest brand. You can’t be lucky or unlucky here, because the modern radio technology achieves the same result in every watch. The all-ceramic Junghans Force is particularly modern and minimalist, while the Junghans Spektrum follows a more traditional aesthetic with Arabic numerals and a ceramic bicolor stainless steel case.

Der Beitrag What are the most accurate watches in the industry? erschien zuerst auf Uhrinstinkt Magazine.

Timepieces with the name suffix “chronometer” enjoy a high reputation, although the exact meaning of the term is not clear to everyone. In today’s article, we clarify the question of what distinguishes chronometer watches and present the most popular models from renowned top brands in different price ranges. You will also learn how three of the most important certificates differ and by which manufacturers they are used.

Chronometer: Definition and main certificates

One of the most common mistakes among watch novices is the confusion between chronometers and chronographs. While the chronograph is a complication (additional function) that enables time stopping in addition to the regular time display, the chronometer describes a precision watch that has received a certificate of chronometer testing from a neutral official institution. To obtain the latter, fine-tuning (regulation) of the time indicator in various positions and at varying temperatures is required. The focus of chronometer testing is whether the time indicator meets specified precision standards. Simply put, chronometer watches are proven to be particularly precise watches.

Timepieces can be awarded their coveted status by various inspection bodies. The most famous is called COSC (Contrôle officiel suisse des chronomètres), is used by most manufacturers and essentially tests whether a movement (still unassembled) has a rate deviation that falls below -4 and +6 seconds daily. More stringent is the METAS chronometer test, which is conducted by the Swiss Federal Institute of Metrology and tests fully assembled watches under demanding conditions. METAS chronometer watches must not deviate from perfect time by more than -5/+5 seconds per day. METAS cooperates closely with Omega, but in theory can be freely used by all brands. In contrast, Rolex‘s “Superlative Chronometer” title is reserved only for the brand’s own luxury watches, is additionally carried out after the completion of a successful COSC test, and requires a maximum deviation of -2/+2 seconds.

METAS: Omega’s precision watches

Launched by Omega in 2015 with the ambition of improving the precision standards of the COSC, the METAS certificate is one of the most prestigious awards in the watch world. Successful “examinees” are allowed to call themselves Master Chronometer watches, which comes with a high status, especially due to the certification of at least 15,000 Gauss magnetic resistance. Interestingly, every METAS movement has already successfully passed a COSC test beforehand. The new generation Speedmaster Moonwatch, launched in 2021, is among the most prominent bearers of the title: equipped with the hand-wound caliber 3861, it offers 50 hours of power reserve and uses a silicon hairspring to ensure long-term accuracy at the highest level.

Automatic chronometers can also be found en masse in Omega’s variety of models – from the robust Seamaster collections to the elegant De Ville. However, some models, such as the popular Speedmaster 38, “only” have a regular COSC certificate. By 2023, Omega aims to change this and call all of its models Master Chronometer watches. Other brands have also recognized the potential of METAS testing – since 2021, for example, Tudor has been awarding its Black Bay with the strict certificate.

Breitling: Each watch has a COSC certificate

Breitling, on the other hand, places its full trust in the proven reliability of the COSC test, which was introduced in 1973, and has been launching all its models as chronometer watches for years without exception. Whether it’s the aviation icon Navitimer, diving legend Superocean or compact ladies’ models like the Chronomat 32 – no flying B makes it to the wrist without an officially certified precision test. That’s especially important for Breitling newcomers to know, because the manufacturer differentiates strongly in price between manufacture movements like the popular B01 and purchased movements based on ETA. The additional price of around 2,000 to 3,000 euros, which has to be paid for the manufacture movement in collections like the Superocean Heritage, is therefore not paid for noticeably higher accuracy, but for 70 hours of power reserve, the complex column wheel mechanism and other technical highlights.

Legendary classics such as the Navitimer 1 B01 Chronograph 43, which already live up to the official distinction in the title and leave no doubt about their certified precision, enjoy the greatest popularity. Those who like it particularly imposing will make the right choice with the new Super Chronomat in the 44-millimeter format.

Rolex: Tighter in-house testing

Rolex’s automatic timekeepers are among the most rigorously tested watches in the industry. Since 2015, in parallel with the launch of the new generation of movements with a whopping 70-hour power reserve (see caliber 3255), the industry’s most famous luxury brand has been awarding the title of Superlative Chronometer to watches that have already successfully passed a COSC test and, after being encased, also pass its in-house testing, which requires extremely low rate deviations of no more than -2/+2 seconds. Power reserve, water resistance, automatic winding and other technical aspects must also meet the toughest requirements.

The prime example of certified horology is the current Submariner Ref. 124060 with caliber 3230, whose blue Parachrom hairspring is one of the central highlights of the modern generation of movements. The brand new Datejust Generation of 2022 (Ref. 126300) with the automatic chronometer caliber 3235 also demonstrates how the Geneva-based luxury brand lives up to its great name through technical excellence. The fact that the superlative timepieces are always accompanied by a COSC certificate creates double security for customers and the certainty that, despite high in-house standards, there is still an independent party involved.

Tag Heuer, Junghans and Co.: COSC as an upgrade

Breitling’s practice of differentiating in its product portfolio between chronometer watches and lower-priced alternatives without the certificate is widespread in the industry. Tag Heuer, for example, tends to ship its entry-level models without COSC testing, while higher-positioned editions have the official precision certificate. The automatic chronographs in the current Tag Heuer Carrera collection (e.g. Ref. CBN2A1A.FC6537) are among the most sought-after models in the brand’s portfolio, powered by the Heuer 02 manufacture movement and boasting a COSC certificate. The same goes for the Autavia Flyback, which performs the stopping, resetting and restarting of its chronograph function with a single push of a button. The entry-level Formula 1 collection also has a COSC certificate in its upscale versions, which can be awarded for quartz movements as well as for mechanical calibers.

The traditional German brand Junghans also gives buyers of its prominent Meister collection the choice between chronometer watches and regular timepieces. One of the most sought-after models among precision lovers is the Meister Ref. 027/4130.00, which combines silvered elegance in the dial with timeless shapes and an automatic movement including an exposed case back.

Der Beitrag The most popular chronometer watches erschien zuerst auf Uhrinstinkt Magazine.