Reply With QuoteIn similar vein:
https://forum.tz-uk.com/showthread.p...ght=storm+aqua
...and in similarish vein:
https://forum.tz-uk.com/showthread.p...ildren-in-Need
Last year I was involved in a forum conversation about a Steeldive 1000m Emperor tuna, actually the one I've got on SC ATM. There was some skepticism as to whether such a cheap watch could achieve such a depth rating legitimately.
For the detractors, the following is very interesting!:
https://youtu.be/nc6qPc0Xjac?si=g_w1Nv21o813IqsT
https://youtu.be/nc6qPc0Xjac?si=g_w1Nv21o813IqsT
In similar vein:
https://forum.tz-uk.com/showthread.p...ght=storm+aqua
...and in similarish vein:
https://forum.tz-uk.com/showthread.p...ildren-in-Need
Wow! A 1,000m diver that ran until 2,786m. That's darned impressive for any watch, let alone a cheapy.Originally Posted by Paul J
Isn't it though?
Armstrong and Miller?
I guess there is always the question about whether the WR ratings on cheapo Chinese watches are real or pure fantasy, so this does suggest that some at least use decent WR tech.
As for the technology to give extreme Water Resistance, as we've observed before, the fact that even cheap watches can have very high levels of WR suggests that the tech for this is well known, and relatively cheap and easy to incorporate if any manufacturer so wishes - as opposed to certain Swiss manufacturers who will spin you endless PR yarns about all their years of research to create a unique product,
Not only that, but it makes a complete mockery of Swiss watches priced comfortably into 4 figures, that have pathetic WR of 30m or 50m, and then have the gall to tell you that such a rating doesn't allow immersion of the watch, even in a swimming pool.
I think it’s more to do with the style of the watch, a slim watch will have a thinner crystal which is one constraint, a thinner case will also flex with less force applied and my understanding is that the case flexing causes the watch to leak because the seals can’t do their job.
What I’ll never understand is how a watch that’s genuinely rated to 30 metres is deemed unsuitable for swimming where the most it’ll be subjected to is around 10 ft of water. Seal designs and systems are often no different on watches rated at 150 metres (or more) versus ones rated at only 30 or 50, the difference has to be attributable to the watch case and crystal and not the seals.
Can’t see the attraction of watches that are like ice hockey pucks, sit high on the wrist, won’t fit under a shirt cuff, but are waterproof at 1000 metres!
Excellent!
https://youtu.be/Wvp-uk1zMa4?si=wcNzX4RjGkuJpEiV
On a similar theme, 200m Seiko turtle fails at 800m with catastrophic failure at 1200m!
And, it was quite catastrophic wasn't it? Impressive though, 4x the depth rating before there was even an issue
Will any owner of such a watch ever go beyond that depth?
No, and most will never come close to anything like that even with a deeper rated watch.
Quite possibly not, but it is the part of the sentence that you didn't quote that is more important.
For instance, Goldsmiths suggest that
For example, a watch with 30 metres water-resistance can survive a rain shower, or getting splashed, but you shouldn't swim in it.
How you swim in a watch, I have no idea, perhaps they mean swim wearing it.
I am heartened to note that Longines, who used to be one of the worst at this, now suggest that you can swim with a 30m water resistant watch. Progress
I know we've been here a million times already, but that quote sums up the absurdity of the WR rating 'system'. 30M is hellish deep - think of a 10 storey building in height - serious scuba dive territory. Either a watch is WR to 30M or its not. To my simple literal mind, if a watch is marked as WR to 30M you should therefore be able to use for frankly almost anything you want in water, or if you can't swim with it on, then mark it 'splash resistant' or whatever.
That would be ideal.
I think to better understand the depth rating system as it stands it should be noted that the depth rating is a static measurement ie the watch is not moving and the pressure is gradually and uniformly increased until it equals the same pressure as 3 atmospheres, 5 atmospheres etc. but during this time the watch is exposed to no dynamic forces which could cause eccentric loading on the case back or crystal.
Rapid and eccentric forces, such as may be caused when diving into the water, for instance, can cause the watch to be exposed to exponential and less predictable forces, in a similar way to that inertia inflicts on a crash victim, which may be equal to several times their own body mass.
Hence, the whole 100m wr for swimming thing; because with a depth rating like that it should be able to withstand any foreseeable forces it's likely to be exposed to.
I hope that helps.
I've regularly swam with a watch rated to 50m, but I'm confident the seals are good. It was pressure tested to 60M as part of a services and I found an example online that was tested to 100m. It also has a screw down crown and case back. I think most of the rating are arbitrary aside for the ISO ones. I also don't think a human is capable of the levels of force production that would change the actual atmospheric pressure to any significant amount.
30m we didn't test but heh, we also sell a diver's watch
50m we might have tested, did I mention we sell a diver's watch.
100m we tested, but didn't try too hard. Anyone for scuba, see above.
200M etc. and says divers we did what ISO or some similar body said, probably.
Last edited by gerrudd; 17th December 2023 at 18:15.
I agree with that point but it was the way you said a 'pathetic WR of 30m to 50m' that made me think, surely anything higher rated is nothing more than watch forum banter. An actual 50m rating should be more than enough for any mainstream watch.
It's very subjective in this regard as do we have to consider the height when diving, the medium (fresh water, salt water) or even arguably the swimming stroke.
given that some watches will actually be used for diving, there must be something more definitive than these arbitrary depth numbers?
Quite, and I think that's where the ISO ratings pick up the thread. You're right of course about the subjectivity and I agree about the potentially misleading nature of stated depth ratings. Personally, I tend to see anything more than 100m rating as more a testimony to materials dimensions than actual usability.
I, like most people would chose a 200m watch over a 100m watch (all other things being equal) but only because it's likely to be a tougher built piece.
Years ago I had an enlightening conversation with the owner of a well known Microbrand during which he told me that other than to get an accreditation or as a marketing stunt, most manufacturers don't test their watches below 100m. This, I was told was done to test that the watch was actually water tight, below that, it's the structural integrity of the whole that is on trial.
That is like saying... if the speed limit is 70mph, all cars sold should not be able to do more than than 80mph. Do you see the issue? Humans will be humans.
THIN is the new BLACK
The velocity thing is baloney. I have done the maths on this on this forum before, but roughly speaking, if you dive in from a good height like 5m you add about 5m worth of depth in velocity pressure. In other words, very little.
Velocity pressure is 1/2 x density x velocity squared.
If you are travelling at 10 m/s (36 kmh, 22.5 mph, the speed reached in freefall from a height of about 5m) that pressure is 1/2 x 1000kg/m3 x 100m2/s2
= 50 kPa or 0.5 Bar
Double it, 20 m/s, a dive from 20m, adds 2 bar. That is a serious impact, but not very much pressure.
And that pressure is only present at that magnitude if it is acting directly on the seal, which it won't be, unless you hit the water crystal or crown first..
My point about "pathetic" WR is that for years many Swiss watches put 30m and told you that the watch was unwearable in everyday situations that might involve water. Showering, washing up etc.
It was all a lie. 30m should easily be enough, for all those things and more, but they refused to stand by their product, making the low ratings pretty pointless and pathetic.
These Chinese watches are proving that 200m and more is easy to achieve at relatively low cost.
I firmly believe there are few excuses for low WR, and no excuse whatsoever for selling WR short, by suggesting (as Goldsmiths do) that 30m is not enough to swim with. It should be.
As I said before, Longines used to be the worst at this. They actually re-issued the Iconic COSD, a military watch specifically designed to be waterproof, with a paltry 3 Bar WR rating, when at the time their stated capability for 3 bar meant you couldn't even go in the shower with it.
I am very heartened to see that their latest spec shows that 3 Bar, 5 Bar, 10 Bar and 30 Bar resistant watches are all suitable for activities in groups 3, 4 and 5, these days.
3 rain, washing your hands
4 showering, taking a bath, washing dishes, doinghousework
5 swimming, snorkelling
Bravo Longines.
Which makes you wonder why they bother with all the different ratings........
As I said, that's the argumentation. I'm a Civil Engineer, not mechanical so I make no claim as to personal knowledge, I'm only passing on what was offered by way of an explanation to me. Marketing it may be, but it's the stated reason for the system.
Thanks due to Sweets for clearing this up, I knew someone had proved this in the past, coukdn’t remember who!
In an extreme case, someone could move their arm at incredible speed whilst submerged at 30metres and thus exceed the pressure rating of the watch.........I think its fair to say this scenario is unlikely!
The key to all this is the condition and integrity if the seals, if the crown seals have either hardened or turned to sticky tar after 40+ years it doesn’t matter how big the number in the dial is, the watch will leak if it gets splashed. There’s a mistaken belief that a watch rated to 200metres will still be OK to swim in after 40 years whereas a newer watch rated to 30 metres won’t. If seals deteriorate the watch goes from hero to zero, it usn’t like tyre tread that deteriorates gradually!
None if this is rocket science, it’s common sense.
Not for some Paul......
When you look long into an abyss, the abyss looks long into you.........
I found this for some additional science: https://www.watchuseek.com/threads/s...-again.610734/
I take your point but it's apples and oranges. It's almost a given that a watch won't travel below the 50m marker in its life. However, many cars will travel beyond 70mph, some are manufactured in countries with few speed limitations, some are used for circuit racing, the list is endless.
I've overheard many a conversation over beer where people, mostly men, have discussed the maximum speed that their cars have done. I've never heard a conversation where people have taken their watch below 50m.
as a side note, I think that every car used on British roads should be road limited to not far in excess of that limit. I believe that the Japanese do it, it's not rocket science. The moment it enters an area where it can go faster, the restriction is electronically removed automatically.
Posting Permissions