I need AT LEAST 500m so I know I can wash my hands relaxed

 

I suppose there is more chance of making an excuse for owning a certified diving watch compared to one certified for spaceflight :0)
There are a number of emotional reasons why we buy these items. Logically something designed to withstand extreme conditions should be well engineered and last longer / put up with a more mundane existence much better. A lot of F1 tech makes it way into production cars for example. Of course a few Alfa Romeo owners might challenge this assumption (in terms or reliability anyway :0)… now I need to put the wastebasket back on my head and practice for the launch party next week :0)

 

My friend, who is a very wealthy doctor, put an addition onto his house that he never goes into,

The point: in many cases, it's nothing more than bragging rights for the owner. Mine is: more expensive, bigger, faster, longer. prettier, rarer than yours is.

 

Bit like buying a METAS watch that’s not as accurate as a $100 Quartz

 

Wow, I won't even begin to go into what's wrong with the referenced link.(well maybe a little). A rudimentary understanding applied to a complex scenario is nearly always folly.

Yes, marketing plays a huge role. But stds exist to compare oranges to oranges. As far as they go of course. I've worked in wet world testing for over 20yrs. Dynamic affects are about forces felt for small periods of time. These forces can spike considerably and dramatically when applied. Static testing isn't even close to real world use of a watch, but how else is a std to be developed and applied given the complexity of possible use? Lots of assumptions, that's how, which basically neuters the true usefulness of most stds. Therefore, lots of product stds are BS, but such is the world of performance testing.

That, and given the temporary lifespan of the results existing for merely the time frame of the test, you can see how hard it is rate this sort of thing.

So what you need is a high factor of safety. Given the physics of true dynamic forces and aging and wear of seals, a smart diver would endeavor to use a watch rated for at least 10x the expected depth of use. Preferably 20 - 30x. Assuming no external damage or other compromising conditions occur.

As an example in my world, a product designed for 1500ft depth would be tested to 30,000ft pressure over many cycles and time. This is to ensure a high factor of safety to account for dynamic effects and aging. Even then, it is not a certainty so statistics are used to calculate a level of confidence, always less than 100% of course. Even with the most rigourous testing, failure is a possibility. Such is the real world.

Personally, I would not consider any rating under 300m for anything more than a splash zone... Washing your car, vigorous sweaty exercise, etc. Under water, even just snorkeling, should be 300m+.

Would a 50m watch work underwater? Possibly, but not with confidence over time.

 

When I decided to get PADI qualified last year, I decided that I wanted to have a watch that was my "Dive Watch". That I could use for every dive I did from the point I started, until the point someday in the future when I can't dive any more.

My criteria were:

1 - Something I liked and would want to look after, that at the same time I could afford, and wouldn't be too upset about if it ended up at the bottom of the ocean and couldn't be retrieved.

2 - Easy to use underwater and on dry land.

3 - Would sustain 30+ years of Scuba diving. Whether I can do the same is a different matter.

I absolutely could have dived with a 50m water resistant casio digital, and there would have been nothing wrong with that.

But I am also a watch nerd. So wanted something cool and interesting (to me), that fulfilled the three desires above.

I picked the CWC Royal Navy Auto MK2 - reasonably affordable, 300m water resistance, and if the armed forces have been using them since 1981, I thought they could probably cope with anything I could throw at them.



These were built to 300m WR, because that's what the MOD specified.

As to why the watch industry makes watches with crazy depths - I guess technological bragging rights.

As to why people buy them, I'd agree with what others have said - personal bragging rights.

Rest assured, that 300m WR sure came in handy, 18m under the surface of the Adriatic.

 

Thank you, the physics of the myth never seemed right to me. My opinion is that watch sellers want to have it both ways. High depth ratings to pump up a sale, but then don't want to deal with a watch that has failed seals.

 

This is an interesting thread and I have enjoyed reading it. I have been on this forum for 4 years and I am close to the 200 post benchmark, although I have no watches that I wish to sell. I understand the concept of static vs. dynamic pressure, although I am not an engineer. I am a PADI certified recreational diver but I don't dive much anymore. I learned how to dive in the early 1990s when I lived in the South Pacific, before the widespread availability of relatively inexpensive, dive-computers. None of the crowd that I hung out with wore Rolex Subs, Omega 300s, or any of the big names - you would see them occasionally on the wrists of rich tourists. Seiko divers and cheap TAG Heuer F1s were very popular with recreational divers before the onset of dive computers.
The water resistance rating of watches is esoteric for the host of reasons that others have stated above. With all of the variables, it is very difficult for a lay person to assess every situation but watch manufacturers have to have some consistent way of rating their watches. The watch that I used for diving was a TAG Heuer 1500 quartz, that I bought new in Singapore in 1992, and it had a 200m rating. It served me very well and I still have it. The deepest that I ever went was 50m and most of the time my diving was at a depth of 5-25m. With that said, 200m is the minimum I would consider for a watch, if I was going scuba diving. Back then, I had it tested every 2-3 years and it never leaked on me.
New, or vintage luxury Swiss watches are expensive to service, and for this reason I don't wear any of my watches in the water anymore. I used to wear my TAG 1500 in the lake at the cottage but if I fell water-skiing at 25mph, the effective pressure on the watch would probably exceed anything it had been subjected to while diving. I have friends who still dive and they all use dive computers. I would do the same.
So why then, do we get hung up on on water resistance, helium escape valves, screw crowns, and bezels? Authenticity and the power of dreams have driven this trend. Marketing campaigns sell dreams - you may never go diving with this watch but you could, if you wanted to... it is built to withstand... to the same exacting standards....etc. That only encourages manufacturers to follow market demands, which drives the techno-weenies, or geeks like me to search out the real McCoy and find the truly authentic article, not the mass market wannabe. This goes well beyond watches, to include sports cars and off-road vehicles. You may never use the capabilities, but if you wanted to, they are there just waiting for you.

 

Have done a lot of work inspecting oil rigs and gear coming off oil rigs and most of the waterproof stuff that goes down to over 50-100m is basically a stainless steel housing with a few O-rings. The wire coming out the back is usually a blob of silicone.

Start going over 200m+ the stuff gets a lot more serious.

 

I will disagree. A higher initial water resistance doesn't really mean that the watch will still be 50% as effective when the seals go bad. When they go bad, the watch leaks and it doesn't matter what the rating is. The vast majority of watches use the same O-rings - simple Buna-N (nitrile) O-rings that fail in time. Once they fail, the additional water resistance means nothing - a watch rated for 1000m goes to zero just like one rated for 50 m.

Cheers, Al

 

Two things - first "dive" watches are a specific class of watches that require very specific features, and one of those is a minimum depth rating.

Second is the subject of how ratings work, which is a different thing. The thing you are right on is that Googling this information and looking at random sites will tell you this. Unfortunately misinformation abounds on the internet.

Any reputable company will not make you Google some third party chart made up by a watch blog, a watch seller's site, or some other entity to "decode" their depth ratings. In the case of Omega, they explicitly state that the rating on the watch is what the watch can go to in terms of depth:



People will argue left and right that this chart doesn't mean that, and will tell you that some blog sire has a chart that is "more right" than the people who actually make the watches. To say this is twisted logic is an understatement.

Cheers, Al

 

The dynamic pressure argument is made by many. This is a better refuting of it IMO:

https://forums.watchuseek.com/f2/sigh-myth-busting-again-610734.html

If anyone wishes to do the math to refute this, then let them show their work...anything other than that is hot air IMO.

Cheers, Al

 

Thank you very much. I learned things today. As per your example I googled A Lange Soehnes guide to water resistance:




Clearly the best option is to look at the manufacturers guide or the watches manual.

P.s. Is there some "dynamic pressure" thingy alluded to in the last paragraph ("No high diving").

 

No idea why this is there. What does "high diving" really mean? What height is considered "high" enough to be "high diving"?

Far too many questions about this sort of statement to tell you why it might be there. As this is the first "sport" watch ever made by ALS, maybe they are nervous about dynamic pressure and their designers and engineers have never actually done the math? Maybe they are not concerned with water resistance at all, but movement shocks? Who knows...you would have to ask them. I can't say they inspire much confidence in the water resistance of their watches though, but then again they are a company that has up until recently, made dress watches that I doubt anyone takes in the water anyway. Very different situation from a company like Omega...

 

Anyone else go 4000 feet? Don't hate on me for my beer choice, it was two for one pricing.

 

Oh dear Dog. I don't hate you, but I definitely feel really, really bad for you!

 

maybe something crazy like this?

.