Rejig of Saucer Style Titanium Dive Watch 2000m (maybe)

[Popgun Pete]

I just used Tuna’s as I bought them when they were simply tools for the job.

 

[Eric802]

In saturation diving the body absorbs a certain amount of gas due to the higher pressures. Nitrogen and oxygen at high levels are bad for you and can cause many problems, so the oxygen level is lower in the breathing air at greater depths and the bulk of the gas is something inert like Helium. The Helium Oxygen breathing gas is known as Heliox and provides the volume to inflate the lungs, but the body only needs a certain oxygen level in the blood. That is where the Helium comes from and because the gas molecule is so small it can get into a diving watch while you are sitting high and dry in the chamber slowly having ambient pressure in the chamber reduced to bring you back up to surface pressure. No chamber exposure, no helium getting into your watch. Some watches like the Seiko Professional 600 and later 1000 don’t need a helium release valve because of the construction of the watch, the works in a ‘Tuna’ go in from the front, and there is no removable case back on those watches. The Tuna Can nickname derives from the cylindical titanium case without its shroud.
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So while you’re sitting in the sat chamber breathing some helium, the helium molecules can enter the watch and therefore need to be released when returning to the surface. That makes sense.

 

[Popgun Pete]

Oxygen at a depth of 10 meters can kill you, that is why simple rebreathers using pure oxygen and a carbon dioxide absorbing canister are limited to that depth or you can go into convulsions. The trick of deep diving is to keep the oxygen to a partial pressure and use diluent gases to push up the airflow volume going into the lungs. Other gas mixes are Trimix which is Oxygen, Nitrogen and Helium, the mix is determined for the working pressure level to be encountered. Nitrogen can give problems such as nitrogen narcosis where the diver loses some degree of control of his faculties when breathing normal air under pressure and also needs to outgas from the blood via the lungs which is what decompression is about, i.e. eliminating nitrogen without bubble formation in the bloodstream. Other noble gases have been used such as Argon and at great depths even Hydrogen. During breathing gas experiments people have paid with their lives when the gas switchover was bungled, often due to human error, not always the diver’s mistake. At extreme depths where divers experience nerve conduction problems in the brain it has been found a reintroduction of nitrogen to the mix has countered this effect. Gas mixes are a demanding science, get it wrong and very bad things happen, a job for experts.

Helium is scarce and expensive, that is why other gases are used in deep breathing mixes.

 

[Popgun Pete]

Another way to improve the grip on the bezel by using peripheral indents. This leaves the saucer shape of the case more or less intact.

 

[Toasterking]

As for a crown at 12 o’clock we had this one a year or so back.
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I surprisingly dont hate this -- but it looks like it is a monster size-wise.

 

[Popgun Pete]

I surprisingly dont hate this -- but it looks like it is a monster size-wise.

When you wear 52 mm in titanium Tunas it is surprising how big this looks when it is only 47 mm. I think watches start at 44 mm unless someone is rather tiny.

 

[davecampbell]

The depth ratings for dive watches are static ratings, the watch being static. However, a watch in use is not static, it is waved and bumped about during use, dynamic. I am not talking about the seal(s), I mean the use of the watch when worn about. You may consider the depth ratings absurd or not but they do carry meaning. A 150 to 200 meter rating is generally good enpugh for a watch wearble during diving activities. Divers in commercial use may need helium valves or due to long and continuous submersion often have very generous depth water resistance ratings.

Two of my favorites to wear and dive with, an EcoZillia and a TiZilla, 300M water resistance, and they have the saucer shape:

I have the same two zillas. they're my favorite watches....by far.

 

[Popgun Pete]

The saucer watch is under review, so I thought I would buy something similar. Makes a change from my Tuna's and only 50 mm in diameter. Bought it on its looks. Kind of heavy at first, then you don't notice it. Pity they don't do it as a quartz, or titanium, but these things can change over time.