Earlier this year, I bought a big batch of watches to resell. Inside the lot, was a mixed bag of quartz watches in different conditions. Some were keepers, some were flippers and others were complete garbage. One of these broken watches had a very interesting complication that I almost missed, but I thought it was so cool (and quirky) that I had to write about it.
Swiss Army made a handful of “Big Date” watches… and the Centurion is one of the earliest
The complication that I am talking about is called a “BIG DATE” and at first glance, you might not even know what you are looking at. Having a date window on a watch is not exactly a new thing. If my memory serves me right, the 1945 Rolex Datejust was the first mass-produced watch with an automatically changing date function. Before this, changing the date on a wrist had to be manually done. Practically everyone has seen a watch with a date window so this is nothing exactly new.
My busted Swiss Army Centurion is interesting because it has a “Big Date”
However, the BIG DATE complication is not as common as a standard date complication, especially on affordable watches like the quartz Swiss Army Centurion seen here. Again, you might be thinking “what’s the big deal? It looks like any other date window, just supersized.” This goes to show that looks can be deceiving and there is some interesting mechanical trickery going on under the dial of this Centurion to make this happen.
This Big Date smells different from a typical single disk date wheel
If you are thinking that Victorinox Swiss Army used a magnifying window like some Rolexes, then you would be mistaken. This Swiss Army Centurion BIG DATE does not have the tell-tale enlargement lens that is sometimes called a “Cyclops” after the one-eyed monster of Homer’s Odyssey. Those mini-magnifiers can be glued on the top of or under the crystal and they enlarge the look of the date disk numbers like a magnifying glass would. Good thing there are not any ants inside the watch, or they sure would get fried (as they might have been in my childhood). haha
Bigger is better in some situations like reading a date
Because my Swiss Army Centurion was trashed, I had considered taking it totally apart to reveal the secrets of the BIG DATE. While I don’t mind doing that, I caught a lucky break as I took off the case back. The quartz movement inside had a number molded into it and a quick Google search later saved me a lot of effort. The movement in the Swiss Army Centurion Big Date is a Ronda 519 Big Date and here it is.
Ronda 519 quartz movement has two date disks. Photos: Ronda
As you can see, there are actually two synchronized date disks inside of the Ronda 519 movement, and they turn independently from one another. You could think of this sort of like an old-fashioned odometer in your car were a lower disk counts upward from 0 to 9 and then the next disk flips over after a base-10 set has been counted. However, there is one major difference and that is there is only a maximum of 32 days in any given month.
You can see the two disks when the date flips over
As you can see, the inner disk only has 0, 1, 2 and 3 on it. You can also see that these numbers repeat to make a total of three sets. Just as strange, the outer disk has numbers from 0 to 9 and they repeat twice. Compared to a typical date wheel seen to the right that counts from 1 to 32, this double disk setup seems a lot more complex. But one thing is for sure, the numbers are significantly larger and can easily be seen without magnification. My old eyes love that!
It’s easy to see the date size difference even from a distance
The “Big Date” is absolutely massive in comparison
Having a BIG DATE complication might make for strange date number combinations. Because my Swiss Army Centurion was not actually working, I can only speculate on how it is supposed to work. If I pulled the crown to the setting that allows me to change the date, I could manually manipulate the date. From the outside, it looks like the date counts upwards as it would normally do to 32, the highest date on our calendars. Then something really quirky happens… the numbers keep going up… 33, 34, 35, 36, 37, 38, 39… and then OO when the date disks align to show snake eyes or double zeroes.
Impossible dates like “33” are possible on a “Big Date”. A manual reset will be required.
This might be one of the only times you will see “00” on a watch face
Because my watch is not working, I can speculate that the user has to reset the date at the start of each month, otherwise, the date will quickly get off track. Luckily, it only takes seconds to do and it is satisfying to see the numbers flip over independently from each other.
The date disks turn in opposite directions as seen here during a date flip over
Admittedly, my Swiss Army Centurion with the BIG DATE is in terrible condition. It may become a watch that teaches me how to replace a crystal and swap a movement. If I break it beyond repair, then I would not have lost much. The best part is that the Ronda 519 movement is less than $13. What a bargain for such an interesting quartz caliber. One thing is for sure if I ever do get it running again… I will be able to see the correct date from across the room.
A Big Date gives a standard watch design visual spice
