Tokunaga ,seiko divers

[george_]

εδω

[george_]

Hello
Mr.Tokunaga
I am curious as to why Seiko uses a base metal for the ceramic coated housing cover for this watch. Why is this a base metal vice stainless steel or titanium?. Does the base metal help with anti magnetic properties for this watch? Also What type of metal is the base metal? How is the ceramic coating applied over the base metal? Is the ceramic coating a powered ceramic paint? Can you give me some information about this.
Thank You In Advance
Jima


Reply:

Hello

The material of the protect cover (outer case body) of Seiko 1000m diver's watch is not coating of ceramics but the solid material of ceramics.

In addition, the expression with "base metal" in the marking of a case is used when the parts which carried out the golden color mean that it is not "gold", and the materials of the base metal are such as brass, nickel silver, stainless steel, pure titanium and titanium alloy etc.

These materials are non-magnetic materials. The duty of anti-magnetic property was not achieved by those parts, but the anti-magnetic plate (please refer to the cross section drawing below) made of pure iron on the inner case body has achieved the duty of anti-magnetic property.

I summarized the materials and surface treatment of those parts on the following image. Please refer to in detail.


I hope this helps you.

Sincerely yours,

Ikuo Tokunaga

[george_]

ABOUT SEIKO MILITARY WATCHES:



In SEIKO, the timepieces belonging to the military watches have been produced from ancient times, and those watches were offered apart from commercial watches. Simultaneously there are so many cases when those who belong to the Department of Defense buy a commercial watch individually for personal use.

In case of SEIKO military watches, there were, for example, the "star mark" printed watch in the dial manufactured from 1935, and the "Anchor mark" and the "Cherry blossom flower mark" printed or stamped on the dial or case back which were manufactured in 1940.

Recently, chronograph watches have been used for military use in British Air Force and a lot of diver's watches have been used in the U.S. Navy or the Maritime Self Defense Force of Japan. Although these are not sold in a general market, when those who belong to the Department of Defense part with the watch, they appear in an antique watch market.

[george_]

subir fotos

[george_]

The caliber 6139 was started from March in 1969 and 6138 was added in June of the next year. These watches were regularly used through the 1970s by the chronograph fan in the world, and evolved into the world's first quartz watch chronograph of 7A28/38/48 developed in early stages of 1980s.

This stuff was made of some catalogs published in the 1970s. Please forgive me for being a bit indistinct. (I carried out translation and scans after color copies)

Only a Japanese model (JP) and a general export model (GE) are found in these catalogs. Therefore, other information, such as a U.S. model, will be welcomed very much.

[george_]

Dear Tokunaga-san

I woudl like to know what years the 6306-7000/7001 diver was produced, and how that affected the 6309-7040/7049 diver. Where both watches bbeing produced durring the same years, and which one came first, the 6306, or the 6309.

I have always though the 6306 21 jewel came first, but I seek your advise on this.

Thank you.

Reply:

Dear

I designed these models from 1975, as the next model of 6159 600m professional diver's watch. So if I am allowed to judge this history from my memory and my saved stuff, it will be as follows.

Both of the 6306 diver's watches for domestic and the 6309 diver's watches for overseas were made in Suwa Seikosha from 1976, and 6306 diver's watches were put on the production "slightly first". Those basic specifications were same except for the number of jewels and the bilingual language display of the calendar.

The reason why I said the "slightly first" is only that I was not able to confirm the start month on the production. I am sure the 6306 diver's watches came first, too.

If speaking from the viewpoint of plans or of technical designing on 6306/6309 diver's series, I am sure the concept of influence or of derivation between those watches did not exist in 1976. It is because I issued the specification drawing of those diver's watches as the same one. This means that I wrote only a description such as "6306 ( Japan ) / 6309 ( Overseas )" on one sheet of common paper in order to show the difference. The drawing below is the original specification drawing of 6306/6309 150m diver's watch (which has been editted).

Incidentally, as for those calibers, the 6309 caliber was designed first. The base caliber of 63 series (about ten) is 6309.


I hope this helps you.

Sincerely yours,

Ikuo Tokunaga

[george_]

Our research and development was done as the perfect He-mixed-gas diver's watch of the 6159 professional 600m diver's watch in 1975.

We designed the diver's watch as the development target that the inner pressure of the watch case did not go up in high-pressure helium mixture gas like Rolex etc., and the development of the special quality gasket of the material of Improved-IIR(Isobutylene-isoprene rubber) and in the structure development of the watch case we used the glass gasket of L type and one-piece case became the conclusive factor in the He-tightness.

As the result of the experiment, the penetration of helium gas is suppressed by about 1/100 to the conventional watch case, the inner pressure of the case does not turn into high pressure and the diver's watch of the ideal saturation diving specification which does not need "helium gas escape valve" is completed, and the SEIKO professional diver's watches lead the diver's watch world after that watch as "a diver's watch which is proud of the highest water- tightness and air-tightness in the world."

Please use forever regularly those SEIKO products which are proud of the excellent performance if you please.

Sincerely yours,
Ikuo Tokunaga"