“Spherodrive” is a term that sounds really cool. I sort of want to shake the hand of the guy who penned it. Funny how the Swiss watch industry still has clever engineering-minded people who come up with this technology and these names. The industry is full of terms such as this like “co-axial escapement, silinvar, constant-force, and magic lever (that last one goes to the Japanese).” Often times these terms are much better than actual watch model names.
A few years ago Swiss Eterna debuted its new Spherodrive technology in a Madison watch. I discussed the Spherodrive Madison with the calibre 3505 movement here. In that article you can also learn a lot more about Spherodrive mechanism itself and what it is all about in comparison to more traditional mainspring barrel assemblies. In short, Spherodrive is a new way for mainspring barrels to connect to movements. It creates a more stable connection and one that is more reliable. It also uses ceramic ball bearings that require no lubrication. This all means that the watch requires less maintenance, is going to be more accurate, and less prone to being damaged over the long run. According to Eterna, before Spherodrive mainspring barrels haven’t been given a lot of attention and should be considered one of a watch movement’s weaker points.
To showcase the debut of the Spherodrive technology in the manually-wound Calibre 3505 movement, Eterna put the movement in a Madison watch. Simple and elegant, people argued that the conservative looking timepiece was perhaps not the most exciting way of debuting the novel mechanism. So Eterna followed up with a new movement called the Calibre 3510. Also manually wound, this movement added a big date mechanism and an 8 power reserve (via two barrels) with a power reserve indicator. Still a Madison, the watch was updated to look more modern and technical. While still a conservative looking timepiece, this Madison Eight Days is easily a better frame to show off the Spherodrive system.