Automatic Watches Explained: How They Work, the Meaning, and Why Watch Enthusiasts Love Them
- Militex Watches
- 6 days ago
- 4 min read
For over a century, automatic watches have fascinated collectors and enthusiasts alike. Unlike battery-powered quartz watches, an automatic watch is a miniature mechanical machine powered entirely by movement. Every swing of your wrist keeps hundreds of precision-engineered components working together in perfect harmony.
Whether you're considering your first automatic watch or simply want to understand what makes them so special, this guide explains everything you need to know.
What Is an Automatic Watch and the Meaning?
An automatic watch (also known as a self-winding watch) is a mechanical watch that winds itself as you wear it. Instead of relying on a battery, it stores energy in a tightly wound mainspring, which gradually releases power to drive the movement.
As you go about your day, the natural motion of your wrist causes an internal weighted rotor to spin. This rotor continually winds the mainspring, providing a constant source of energy.
The result is a watch that can continue running for decades—even generations—with proper servicing.
How Does an Automatic Watch Work?
Although beautifully complex, the principle behind an automatic watch is surprisingly simple.
1. The Rotor
Inside every automatic watch is a semi-circular weighted rotor that pivots freely through 360 degrees.
Whenever your wrist moves, the rotor swings with the movement.
2. Winding the Mainspring
The rotor is connected to a series of gears that wind the mainspring.
As the spring tightens, it stores mechanical energy ready to power the watch.
3. Releasing the Energy
The mainspring slowly releases its stored energy through an intricate series of gears known as the gear train.
This energy eventually reaches the escapement, which regulates the release of power into precise, consistent intervals.
4. Keeping Perfect Time
The escapement works alongside the balance wheel, which oscillates back and forth many times every second.
This is effectively the heartbeat of the watch, controlling the movement of the hands and keeping accurate time.
What Happens If You Stop Wearing an Automatic Watch?
Unlike quartz watches, an automatic watch won't run forever once it's taken off.
Most modern automatic movements offer a power reserve of around 40–42 hours, meaning the watch will continue running for nearly two days after it's has been removed.
Once the stored energy is exhausted, the watch simply stops.
To start it again, you can either:
Wind the crown manually
Wear the watch for a period of time while it rewinds itself
Can You Wind an Automatic Watch by Hand?
Yes.
Nearly all modern automatic watches include manual winding.
This allows you to fully charge the mainspring before wearing the watch or after it has stopped.
It's a useful feature if you rotate between several watches throughout the week.
Why Enthusiasts Love Automatic Watches
Automatic watches offer something quartz watches simply cannot replicate—the appreciation of traditional mechanical engineering.
Many owners enjoy knowing that their watch contains dozens or even hundreds of moving parts, all working together without electronics or batteries.
Other advantages include:
No battery changes required
Traditional mechanical craftsmanship
Smooth sweeping seconds hand
Long service life when properly maintained
A deeper connection between the wearer and the watch
For many collectors, owning an automatic watch is as much about appreciating craftsmanship as it is about telling the time.
The Automatic Movements Used by Militex
At Militex, we've selected proven Japanese automatic movements renowned throughout the watch industry for their reliability, durability and ease of servicing.
The Militex Scuba King
The Militex Scuba King collection is powered by the dependable TMI (Seiko) NH35A Automatic movement. This respected 24-jewel calibre features automatic winding, manual winding, hacking seconds for precise time-setting, and approximately 41 hours of power reserve. Combined with a 39mm 316L stainless steel case, domed sapphire crystal, Super-LumiNova C3, and 100 metres of water resistance, it delivers classic mechanical watchmaking with everyday practicality.
The Militex GMT-Aeroglobe
For travellers and adventurers, the Militex GMT-Aeroglobe is equipped with the TMI (Seiko) NH34A Automatic GMT movement. Alongside all the benefits of a traditional automatic movement, the NH34A features an independently adjustable 24-hour GMT hand, allowing the wearer to track a second time zone with ease. With its 41-hour power reserve, domed sapphire crystal, screw-down crown, and vintage-inspired styling, it's designed for those who appreciate both heritage and functionality.
Do Automatic Watches Keep Good Time?
Modern automatic watches are designed for dependable everyday accuracy.
Movements such as the NH35A and NH34A are widely respected throughout the watch industry because they're robust, easy to service, and built to withstand years of regular use. Typical accuracy is around –20 to +40 seconds per day, which is normal for reliable mechanical movements in this class.
Many enthusiasts actually enjoy these tiny variations, seeing them as part of the charm of owning a living mechanical machine rather than an electronic device.
Why Choose an Automatic Watch?
An automatic watch is more than a way to tell the time.
It's a celebration of engineering, craftsmanship and tradition.
Every movement of your wrist keeps a tiny mechanical masterpiece alive—a technology that has been refined over generations and continues to captivate watch lovers around the world.
If you're looking for a heritage-inspired automatic watch built in Great Britain using dependable Japanese movements, the Militex Scuba King and GMT-Aeroglobe collections combine timeless design with proven mechanical performance, offering exceptional value without compromising on quality.
