elliot55
2817
Okay, here's the deal...
Jun 23, 2012,10:07 AM
... look at your mechanical watch... the second hand is 'sweeping', as it does on almost all mechanical watches - except for those fitted with a complication known as a "deadbeat second hand". A quartz watch has a second hand that does not sweep and clicks one second at a time, but it is not called a deadbeat second hand because it is just how a quartz watch works. It is for this reason that a deadbeat second hand on a mechanical watch is actually considered a complication.
Now if you were to look very closely at that sweeping seconds hand on a mechanical watch, you would see that it actually makes 8 tiny little moves per second and only looks like it is sweeping. On a watch with a 28,800vph heartbeat, the regulator will drive the palette fork back and forth 4 times (for a total of 8 contacts) per second. The sub-dial at nine o'clock on the Habring Foudroyante is actually showing the 8 contacts the palette fork makes per second. And so, the sub-dial makes a full revolution every second for a total of 86,400 revolutions per day! And yes, the second hand is a deadbeat second hand - which makes every second count!
Here's a great video of the Habring Foudroyante in action - http://www.youtube.com/watch?v=WbNQkZAWpCc
The Duometre from JLC, for example, has a heartbeat of 21,600 vibrations per hour - meaning this watch's palette fork makes three trips back and forth (for a total of 6 contacts) per second. Hence, the Duometre has been fitted with a 1/6th of a second foudroyante at six o'clock.
Here's a great video of JLC's Duometre in action - http://www.youtube.com/watch?v=jWFrR_C_Sks
Note: The Duometre's foudroyante hand only runs when the chronograph is activated. The Habring's foudroyante hand runs all of the time.
To sum up, a foudroyante has traditionally been found on chronographs measuring 10ths of seconds. Keep in mind, that chronographs are not designed to have the 10th of a second hand running all the time. It took Richard Habring a good couple of years to design a foudroyante that could handle the stress of running all the time. Hope that clears it up.
- Scott
This message has been edited by elliot55 on 2012-06-23 10:11:55