For a whole assortment of reasons, some good and others bad, Tudor’s Black Bay P01 turned heads at this year’s Baselworld. Without a doubt, however, the most polarizing detail was the large locking bezel mechanism, a design pulled from a military prototype produced by Tudor back in the day. That mechanism, and its modern incarnation to some degree, was one driven by function, and for someone like myself and the latent engineer hidden somewhere deep inside me, I found it delightfully appealing. Now, I rarely need a timing bezel, let alone the safety that comes from a unidirectional one, so a bezel lock adds a further level of purpose to the design that I have no need for. With that said, I can’t help but like it.
Today, I’m going to take a look at some other bezel-locking mechanisms that have adorned dive watches over the decades, including quite a few that are readily available today.
To understand the solution that these locking mechanisms offer, one must first understand the problem. As a very fast and loose summary, the rotating bezel is a simple and effective tool — a quick way to set a marker against the minute hand, which then acts as an indication for reading the elapsed time. Different bezel markings can offer more utility in this area, including decompression bezels, but that’s enough grounding to set the scene. Now, if a bezel can be turned by hand, then it follows that it can be accidentally knocked and rotated. Blancpain filed the original patent for a unidirectional bezel, which means that should it get moved unintentionally, it will show a greater time between the bezel position and the minute hand. If your dive watch is going to give false information, then it’s far better to overestimate the elapsed time rather than underestimate it.
“The Yema Superman, which dates back to 1963, is often credited as the first dive watch with a locking bezel.“