« An Eternal Debate »
Most mechanical wristwatches today are fitted with an automatic winding mechanism. Yet models with manual winding continue to come onto the market. Which of the two is preferable is a question watch enthusiasts have answered in very different ways for decades. That is unlikely to change anytime soon, since not only rational but also emotional considerations play a major role.
Manual Winding: The Purist's Choice
First of all, it's worth noting that anyone drawn to a mechanical watch that is as original as possible and pared down to the essentials will still happily reach for a manual-wind model today. After all, winding mechanical watches by hand is a tradition several centuries old, whereas automatic watches are a considerably more recent invention that only began to catch on in the market on a larger scale around the middle of the 20th century. One occasionally perceived drawback of a manual-wind watch is that its wearer has to wind it regularly. Those who prefer manual winding, however, often see this as a cherished daily ritual they wouldn't want to give up.
Today, wristwatches and pocket watches are usually wound by turning the winding crown, which was developed by the manufacture Patek Philippe in 1845. Until then, special winding keys were generally required. Incidentally, it's advisable to wind a manual-wind model at roughly the same time every day. Granted, most models offer a power reserve of around 40 hours, well beyond a single day. However, the watch's accuracy can decline once the mainspring has only little tension left.
With Automatic Watches, Enthusiasts Appreciate the Ingenious Engineering
Automatic watches don't need to be wound every day, provided they are worn daily. They essentially wind themselves as the rotor of their automatic movement is set in motion by the wearer's arm movements. Unlike manual winding, automatic winding takes place in small increments on a more or less continuous basis. A slipping clutch prevents the mainspring from being overwound if the watch keeps moving after it is fully wound.
For many fans of automatic wristwatches, this type of winding is not only a practical innovation but also another step toward ever more sophisticated mechanical watchmaking. Early automatic watches, by the way, used so-called oscillating weights instead of today's standard rotor, commonly known as "hammer" or "bumper" automatics. Over time, however, the rotor clearly won out.
Automatic Winding Delivers Greater Accuracy
Because automatic watches are in almost constant motion in everyday wear and are therefore wound fairly continuously, the introduction of automatic winding mechanisms also brought a noticeable improvement in accuracy. The power reserve of automatic watches is usually around 35 to 60 hours. By combining several barrels, however, power reserves of up to ten days can be achieved.
As a rule, mechanical wristwatches should be kept running as continuously as possible rather than left stopped for long periods. That's why automatic watches that won't be worn for a while are often stored on dedicated watch winders, which use a small electric motor to simulate the movements of a watch worn on the wrist, keeping the mainspring under constant tension.
Manual Winding Allows a Slimmer Profile and a Better View of the Movement
Not having to wind by hand and greater accuracy are two practical arguments in favor of automatic watches, but there are practical reasons in favor of manual-wind watches as well. Since no rotor has to be housed in the case, they can be made considerably slimmer than watches with automatic winding.
This is why elegant mechanical watches in particular, worn for formal occasions or with eveningwear, are still frequently equipped with manual winding today.
Another reason may be more aesthetic than practical, yet for anyone with a deeper interest in mechanical watches it plays a role not to be underestimated: manual-wind models offer a far better view of the working movement, provided the watch has a sapphire crystal caseback.
With automatic models, by contrast, much of the movement is usually hidden by the rotor.
Automatics Tend to Show Less Wear
One practical drawback of manual-wind watches can be that daily winding puts more strain on the crown gasket, so water resistance may diminish after extended use. Eventually, the tube gaskets may also need to be replaced.
In contrast, the rotors of high-quality automatic watches show hardly any signs of wear, even after years of use.
For Collectors, the Race Remains Open
All things considered, collectors of mechanical watches in particular will likely find it hard to come down clearly for or against a particular winding system. Both represent specific developments in watchmaking history, and both have their advantages and disadvantages in aesthetic as well as practical terms. So it's no surprise that in many watch collections, manual-wind and automatic models sit peacefully side by side. And that is unlikely to change for the foreseeable future.