The ligne predates the invention of the metre and the metric system.

A Sellita technical documentation regarding the automatic Calibre SW 200-1 – with its diameter still measured both in centimetres and lignes. For instance, if 11 ½”’ equals 25.9 mm, a movement like the ETA 2824 or its Sellita clone is 25.60mm in diameter and presented as an 11 ½”’ calibre. The ligne is still used in a rather approximative way though by watchmakers. Conversely, a millimeter equals 0.443 lignes. It is still being used today to denote the measurement of the diameter or the calibre of a movement. The ligne is an ancient French measure that has become an established member of Swiss watchmaking folklore – Swiss watchmaking has a lot to do with French culture. This unit is the “ligne” and today we tell you what it is and why it even exists. And if you’re into watchmaking, you might have spotted one of these old units when it comes to measuring a movement, without really knowing what it means, or where it comes from. Each country, each culture, sometimes even each corporation had its own units and ways to measure its commodities or production. Here’s what that looks like in action: a watch with a frequency of four Hz makes four full oscillations per second, or eight vibrations, which adds up to 28,800 vibrations per hour.While today the world relies mostly on two measurement systems (metric and imperial), things haven’t been always that simple. A half oscillation, meaning a swing of the wheel in either direction, is equal to one vibration. Hertz refers to the number of oscillations that the balance wheel in a watch’s movement makes in a single second. If the cast of Rent ever bothered to ask the humble timepiece how it measures, measures the 525,600 minutes in a year, the watch would reply, frequency.Ī watch’s frequency is measured by two different terms: hertz (Hz) and vibrations per hour (VpH) (Don’t worry, they’re interconnected). So here, we'll be breaking down the meaning, history, and importance of different watch terms. Browsing-and even buying-means being barraged with inscrutable words and phrases like ' tourbillons,” “ perpetual calendars,” “ minute repeaters,” and so on. Reading about watches can often feel like cracking open a textbook.

Calibre watch meaning