From Tissot to Omega: watch owners of all price classes know the problem of an automatic watch ticking too slowly or too fast. Not adjusted for a few weeks, the time indicator runs several minutes behind the exact digital clock. Your watch is slowing down? Our magazine tells you which rate deviations are normal, which reasons are responsible for the slowing down, and how you can restore the best possible precision to your automatic or hand-wound watch.

All mechanical watches run inaccurately

“My watch is always running behind!” Every day, German watchmakers and jewelers are confronted with distressed owners whose mechanical instruments noticeably deviate from atomic time. The intensity of the misalignment varies: While some time indicators reveal only three seconds of daily delay, others move several minutes away from the ideal time. We can reassure the former group: If the inaccuracy falls within the range of minus ten seconds to plus ten seconds within 24 hours, we can talk about a precise watch. Tiny differences in the mechanical construction and regulation ensure that two copies of the same watch model can differ noticeably from each other. Whether you catch a model that happens to be close to the zero-second deviation is a matter of luck. If you expect (approximately) perfect precision, you have to buy a quartz watch.

Which rate deviations are uncritical?

Is your watch slow? Watch manufacturers can influence the size of the window in which the potential deviation lies on the one hand by the quality of the components and construction of the caliber, and on the other hand by the position of the regulator in various positions. Gravity, friction and possible imbalances between movement components ensure that precision varies depending on the position of the time indicator. To compensate for this imbalance, the Swiss Chronometer Testing Center (COSC) prescribes five positions in which movements must be regulated: Dial up/down, Crown up/down and Crown left. At the end, the average daily rate deviation is calculated. The coveted certification is awarded in the following cases:

• Automatic watch loses: Up to minus four seconds per day is allowed.
  Automatic watch gains: A maximum of plus six seconds daily is COSC-worthy.

The same standards apply to hand-wound watches. Luxury brands such as Breitling and Chopard use the renowned COSC process, as do more affordable manufacturers from Tissot to Hamilton, to guarantee customers a recognized minimum standard of precision.

Omega goes one step further with its METAS certification: regulated in six positions, the time indicators may advance by a maximum of five seconds (automatic watch loses: failed!) and must withstand strong magnetic fields of up to 15,000 gauss.

Rolex’s in-house “Superlative Chronometer” certificate is particularly strict: over plus/minus two seconds a day is not allowed. But as you can see, no mechanical system delivers one hundred percent precision.

Automatic watch is slow: Causes

The watch is slow – and now? If the deviation is noticeably more severe than the COSC tolerance, for example 30 seconds a day, action is required. Instead of taking action personally and, in the worst case, causing thousands of euros in damage, you should take the model to a watchmaker. The latter will first identify the reason for the malfunction, which can be of various natures:

• Revision required: Every mechanical movement requires regular maintenance (typically every five to eight years). In the course of this, primarily oils are changed and worn components are replaced. If this work is not done, massive inaccuracies result, up to and including drying out and damage to the caliber.
  Coils are magnetized: smartphones, music boxes, magnetic clasps on handbags – mechanical watches can become magnetized by everyday influences. Harmless on a small scale, but extreme cases manifest themselves clearly: the automatic watch goes ahead – and for several hours! This is exactly the reason why the METAS certificate gives such high priority to magnetic resistance.
• Violent shocks: If the hairspring suffers a violent blow, its last handling can jump out of position. The result: the automatic watch slows down. Misaligned hairsprings and a stuck hairspring are also common causes.
  Water in the movement: Diver’s watches need a regular check of their water resistance. If liquid penetrates the mechanics, damage will follow.

Watch is slow: Solving the problem

Not only for reasons of technical fascination, but also in everyday life, inaccuracies are problematic: If the watch is lame, unpleasant consequences result, from missing the train to being late for important appointments. Regardless of whether it’s a Hublot, Breitling or Chopard – massive inaccuracies have to be corrected by a professional. Often, a simple readjustment of the caliber is enough for the watchmaker to mitigate the after-effects. In other cases, a complete overhaul or repair is required. The longer one delays the necessary work, the more serious the damage and higher the costs. Those who keep to the intervals often get away with comparatively inexpensive cleaning. Even brand-new timepieces need a check: freshly broken-in watches should be checked for their rate behavior after a few weeks and readjusted if necessary.

By the way, the quartz clock is not completely excluded from maintenance. Despite a new battery, many owners are surprised to discover: the time indicator slows down! The most common reason is aged lubricants in the gear train, which make it difficult to turn the gears, demand higher torque from the stepper motor and increase its susceptibility to errors. The digital clock is not susceptible to this problem, because the oscillations of the quartz are not passed on to mechanical hands via gear train, but to a digital counter unit.

Tips for the proper care of automatic watches

The automatic watch slows down – there are many causes and professional solutions as well. But what can you do independently to reduce the rate deviation and limit wear? An important factor is the nightly storage. The automatic watch is slowing down? Try a side position with the crown facing up. Conversely, a crown-down position can help “slow down” a watch that is running ahead.

In addition, excessive wear caused by extremely jerky hand movements should be avoided, because otherwise the hairspring could roll over or setting springs could leave their place. Strong temperature fluctuations also damage the movement, which is why many enthusiasts swear by wearing it on their wrist at night. When not wearing your watch for long periods of time, make sure to store it gently, clean your Hublot, Rolex and co. carefully and keep the necessary maintenance intervals. And no matter how detailed the video instructions on the Internet are: As a layman, you should never open the timepiece on your own to perform amateurish adjustments.

Der Beitrag The automatic watch is slow 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.