Watch Notes

The crystal is the clear cover over the dial, and it's the part of a watch most likely to get scratched. Spec sheets list it as sapphire, mineral, Hardlex or acrylic, and the difference affects how your watch will look after a few years of daily wear. Here's what each material means and which one is right for you. A domed crystal on an affordable diver. Many budget watches now use sapphire. Photo: Francis Flinch , CC0 , via Wikimedia Commons. In this guide The short answer The four materials compared Each material in detail Anti-reflective coating How to tell which crystal you have FAQ The short answer Sapphire is the most scratch-resistant and the best choice for an everyday watch. Mineral glass is cheaper and scratches more easily. Hardlex is Seiko's own hardened mineral glass: tougher than ordinary mineral but not as scratch-proof as sapphire. Acrylic scratches easily but is nearly shatterproof and can be polished back to new in minutes. The four mater...

An automatic watch that stops is alarming, but in most cases nothing is broken: the watch simply ran out of energy. This guide walks you through the checks in the right order, from the free 30-second fixes to the signs that mean a trip to a watchmaker. The rotor (the half-moon weight) winds the mainspring as you move. If it isn't moved enough, the watch stops. Photo: Petar Milošević , CC BY-SA 4.0 , via Wikimedia Commons. In this guide First: the 60-second test Troubleshooting flowchart 7 common causes When to see a watchmaker FAQ First: the 60-second test Before anything else, wind the watch by hand. Unscrew the crown if needed, leave it in the pushed-in position and turn it clockwise 30 to 40 times . Then set the time and watch the seconds hand for a minute. It runs normally: the watch was simply out of power. Read the causes below to find out why. It runs for a few seconds, then stops: something is wrong mechanically. Skip to when to see a watchmaker . It doesn...

If your mechanical watch suddenly gains minutes a day instead of seconds, there's a good chance it isn't broken at all: it's magnetized. Phones, laptops and bag clasps are full of magnets. The good news is that magnetism is easy to test for at home and takes seconds to fix. Here's how. Under the balance wheel sits the hairspring, a coil thinner than a hair. Magnetism makes its coils stick together. Photo: Guy Sie , CC BY-SA 2.0 , via Wikimedia Commons. In this guide Why magnetism makes a watch run fast Signs your watch is magnetized The compass test How to demagnetize a watch Common magnet sources to avoid FAQ Why magnetism makes a watch run fast A mechanical watch keeps time with a balance wheel and a hairspring that "breathes" in and out several times a second. Most hairsprings are made of a steel alloy. If they're exposed to a strong magnetic field, the coils become slightly magnetic and cling to each other. The spring then behaves as if it...

Setting the date on an automatic watch takes ten seconds, but doing it at the wrong time of day is one of the few everyday mistakes that can actually damage the movement. Here is the safe, step-by-step method, plus a clear explanation of the "date danger zone" and why it exists. A classic date window at 3 o'clock. Behind it, a date wheel is slowly being pushed forward every evening. Photo: anna2005 , CC0 , via Wikimedia Commons. In this guide The short answer What is the date danger zone? Step-by-step: setting the date safely Crown positions explained Day-date watches Common mistakes FAQ The short answer Move the hands to around 6:30 first, then quick-set the date, then set the time. At 6:30 the hands are as far as possible from the date-change mechanism, so the quick-set can turn the date wheel freely. Avoid using the date quick-set when the time shown is roughly between 9 pm and 3 am . What is the date danger zone? A date doesn't flip instantly at ...

The Seiko NH35 and NH36 power a huge share of affordable automatic watches, from the Seiko 5 Sports range to hundreds of microbrand divers. They look nearly identical on paper, so which one is in your watch, and does it matter? Here is a clear breakdown. A day-date Seiko 5. The day-and-date display is what separates the NH36/4R36 from the date-only NH35/4R35. Photo: Joe Haupt , CC BY-SA 2.0 , via Wikimedia Commons. In this comparison The short answer Side-by-side specifications NH35/NH36 vs 4R35/4R36 How to tell which one you have How to set the day on an NH36 Which should you choose? FAQ The short answer The NH35 shows the date only. The NH36 shows the day and the date. Mechanically they are the same movement: same beat rate, same jewels, same power reserve, same accuracy specification. The NH36 simply adds a day-wheel complication. 21 NH35 / 4R35 date only WED 21 NH36 / 4R36 day + date The fastest way to identify the movement: a date window ...

Your automatic watch is gaining time, maybe a few seconds a day or several minutes. Before you send it for service, it helps to know what is normal and what is not. In most cases the cause is simple, and in one very common case you can fix it yourself in seconds. An automatic watch's rate depends on its balance wheel and hairspring, the parts most affected by magnetism and shock. Photo: Francis Flinch , CC0, via Wikimedia Commons. In this guide How accurate should it be? How to measure the error Cause 1: Magnetization Cause 2: Resting position Cause 3: Power reserve Causes 4–6: Shock, temperature, service Quick troubleshooting table FAQ First: how accurate should your watch be? Mechanical watches are never as accurate as quartz. Each manufacturer publishes an accuracy tolerance per day: Movement Official tolerance (per day) Seiko NH35 / NH36, 4R35 / 4R36 -20 to +40 seconds Seiko 7S26 -20 to +40 seconds Seiko 6R35 (Prospex, Presage) -15 to +25 seconds Miyota 82...

An automatic watch winds itself while you wear it, so why does it stop on your nightstand, and should you ever wind it by hand? This guide covers exactly how to wind an automatic watch, how many turns it needs, whether you can overwind it, and the small mistakes that cause most problems. The crown is used to hand-wind, set the date and set the time. Photo: Pittigrilli , CC BY-SA 4.0 , via Wikimedia Commons. In this guide Quick answer How an automatic watch winds itself How to hand-wind, step by step Can you overwind it? Watches that can't be hand-wound Setting the time and date safely How often to wind FAQ Quick answer If your automatic watch has stopped, unscrew the crown (if it is a screw-down crown), leave it in the first position, and turn it clockwise about 30–40 times . Then set the time. If your watch cannot be hand-wound (for example the Seiko 7S26 in older Seiko 5 and SKX models), gently swing or shake it side to side for about a minute instead. You cann...