In the mid seventies, when the fall of the traditional swiss watch making industry inevitable, some known brands rore up a last time and produced technically and unconventional movements and technologies.
The Tissot caliber 2251, an almost complete plastic movement, was among those movements. It belonged to the last issue of “Astrolon” movements and only showed the time, no date.
On this movement, not only the escapement parts and all gears were made of plastic, but also all plates and briges. Today, this is very common, e.g. on quartz alarm clocks, but at that time, it was revolutionary. The number of parts was also reduced to almost the half of those of a conventional movement. To achieve this, there were no screws at all, no complex mechanisms and so on.
As interesting as it sounds, as horrible are those movements for a watch maker. Since all plates only stick together and all springs are just sticked, too, it is very difficult to do any work on the movement. And the balance brige is only sticked, too, which means, that it is almost impossible to adjust and leads either to a sticky balance or to a balance, which tumbles around.
The Astrolon technology promised longevity and no needs for a service and lubrication, but the specimen shown here, proves, that this was just theory. This watch only got normal wear, but stopped running maybe due to missing or bad original lubrication or whatever might be wrong. It’s almost impossible to find the reason for the bad behaviour, maybe it is just worn out after some years.
Nevertheless, the Tissot caliber 2251 is a very unique and rare movement and thus a highlight of every watch collection.
|Number of jewels:||1|
Nickel anular balance|
|Balance bearing / direction hairspring:||Bridge|
|Adjust mechanism:||Hairspring key|
|Winding mechanism:||yoke winding system|