How had been these ‘bumper’ winding mechanisms totally different from the Rolex spinny weight? As a substitute of the winding weight operating in an entire circle round a central pivot, the load moved via a smaller arc with a spring at every finish. Because it reached the tip of its journey, the load bumped towards one of many springs and was despatched again to its start line the place it was bumped once more, so winding the watch.
Alpina has taken the thought of the bumper motion, up to date it and used it of their new Startimer Pilot Heritage Manufacture. They’ve referred to as their motion the AL-709 – it’s a manufacture motion, too (the clue’s within the identify) and you may see it on show via the watch’s clear sapphire caseback.
The place most classic bumpers’ winding weights ran via a 120° arc, the brand new AL-709’s runs via 330°, so there’s extra winding motion available. On the identical time, Alpina have ditched the springs at both finish of the arc for a sprung and pivoted cease, so there’s extra movement to impart to that weight. It’s a 26 jewel motion and beats at a really un-Fifties 28,800vph. Blued screws are a cultured contact and the plates are completed to look just a little just like the form of brass you’d see on an unique classic bumper.