Part 4 What they don't tell you when you buy a 2015 Seiko Prospex Marinemaster Professional 600m Spring Drive SBDB011 JDM

Part 4...

There is much more...

Here's Part 1, Part 2 and Part 3 if you need check them out...

Enjoying...

Handsome...

One of my books arrived ahead of schedule. From Amazon Japan...Japanese service at its best :-).

Condition like new.

Nice illustrations.

A lot of info from illustrations alone...strictly Japanese readers only :-(...but one can discern somewhat :-)

I guessed right. A chapter on the SBDB001. The front page model of this book, the SBDB001(2005) is the first ever release of a Spring Drive calibre Marinemaster, essentially the same as the later SBDB011(2005), save for different crown logos and no Diamond Shield coating.

This page alone answers many wild guesses owners may have had in the past.

Continuing from Part 3....some more info has come to light:

10)

The SBDB001 and SBDB011 uses a split(dual) detent spring for the bezel ratchet mechanism.

This rare exploded diagram says it all. A small misrepresentation was that the O-ring housed in the bezel inner side was not shown.

Side view becomes so much clearer with the exploded diagram above this one.

11)
Take the following with a grain of salt...

The He-GAS diving abilities of the watch is further confirmed by the following:

Designed for saturated gas diving environment. Wordings mention the SBDB001(meaning SBDB011 also) in relation to another 600m diver from 1986, the Vintage Ashtray 600m Tuna 7C46-6009.

Pic from web. Vertical: Pressure inside watch case relative to ambient. A, B, C (other watch brands) vs Seiko Professional.

I, being the current desktop diver that I am, now faced with this very interesting saturation diving topic can only say the following with some safety:

1. There won't be too much seepage of helium past the SBDB001's watch case seals versus brand A, B and C watches....
2. Seiko's seal design overcomes the need for helium release valves(HRV)...
3. Watch crystals can withstand higher external pressure much better than higher internal pressure within the case...
4. Of course the test is no where near the limits of what the SBDB001 watch was designed to do. Twice the depth and possibly twice the duration should be within the design bounds of the Seiko.

Do not at any point whilst at the deep point(in the living chambers) unscrew the crown and then retighten it! I believe this would instantly equalise internal to external pressure and as the personnel transfer chamber returns to sea level with decompression, your Seiko Professional might crystal pop (Only my conjecture) since it holds the helium inside much better too!


Until the next blog...Cheers.