The differences between a mechanical and automatic watch

All too often, we don't know how to distinguish an automatic mechanical watch from a hand-wound watch.
Let us explain the difference between these movements, what they have in common, and how to easily distinguish them!

The family of mechanical watches

Mechanical watches are actually a “large” family in which manual winding movements and automatic winding movements coexist. On paper, it may seem complicated to understand how they work and their differences, but it is actually quite simple: These two mechanisms are simply mechanical, there is no electronics inside (unlike quartz watches which operate using a battery). Thus, the only difference between these two types of calibers lies in a few components: those of the oscillating weight. Let's see all this in detail!

The differences between a hand-wound watch and an automatic watch

As we saw in a previous article, a mechanical watch works thanks to a spring. This spring needs to be compressed to work. On a manual watch, we can only wind this spring (or compress it) by turning the crown.
On an automatic watch, we can also wind the spring using the crown. In addition, we have a component, called an oscillating weight, which when it is in motion (as soon as you wear or move your watch) will provide the energy to wind the spring. So, if we wear our watch every day, we no longer need to wind our movement using the crown! So an automatic watch is a hand-wound watch on which an oscillating weight is grafted. Of course, about ten components are added at the same time that we present to you in detail.

Technical differences

With this oscillating mass are added wheels that will make the link between the mass and the spring. On the movement itself, which serves as the basis for the automatic movement, only one part really changes: the spring.

Indeed, on a hand-wound watch, it is attached to the end of its compartment, called the barrel. This is why after several turns we can no longer wind the watch.

But, if we add to this a mass that winds the watch even with a fully wound spring, the latter would break. This is why on an automatic watch, the spring is not fixed and slips once it is fully wound. This is why it is possible to wind an automatic watch infinitely thanks to the crown.

To conclude, the family of mechanical watches includes hand-wound watches and automatic watches. They both have mostly similar components and generally work in the same way with the exception of the oscillating weight.

SOURCES:

• Barrel spring photo:
  All about the Barrel Spring - Antenen Swiss
  https://www.youtube.com/watch?v=BSURPbINir8