The Instrument Watch of Professional Divers
have always been occupied by the problem of water- proofness. Water, vapours,
dust and volatile chemical agents arc cunning and formidable enemies of a
watch. We have solved this problem, and our waterproof models are perfectly
safe for normal everyday use.
However, other qualities than normal waterproofness are needed in watches for serious underwater work and underwater sport. Skin - and SCUBA - diving are both rapidly growing in popularity. Now, no-one takes deep-sea diving lightly; the deeper you go, the more pressure you are under. And this same pressure is felt by your watch, so it must be absolutely waterproof. It must indicate exactly how much time the diver has left, without the need for manipulations and complicated calculations. It must be clear enough for the diver to check his decompression stages accurately, and it must be luminous enough for the darkness of the deeps. Finally, it must be tough enough to stand up to bumps and bangs that would throw a lesser watch off balance.
All these qualities can be found in the Seamasters 120 and 300; both were built to last, built to play a vital role, and built to take anything the amateur diver could hand out to them.
'Die exploration and exploitation of the sea has begun in earnest. The untold riches of the oceans are attracting international enterprises, and with them professional divers; divers who need equipment of absolute and guaranteed reliability. The last simulated caisson experiment made it possible for men to live at minus 1,500 ft, and foreshadows exploits which in daring and value will equal those of the astronauts.
And so, to complete and crown the Seamaster range we developed the 600, the most highly perfected and reliable watch for professional divers.
Perfecting the 600 was a long and costly procedure. Years of research, the help and advice of specialists, public relations efforts in professional quarters, all went into the 600. Our prototypes have taken part in experimental diving tests to 1,800 ft in helium and 750 ft under water. They are being used at present in all the great experiments, especially those of COMEX; the last of which, Operation “Janus”, was resoundingly successful.
In the conception of the 600, we left nothing to chance. Every risk was calculated, and the slightest details were minutely considered, so as to give the new Seamaster maximum reliability.
Our technical department has specially adapted a helium leak detector for intensive tests of the 600’s waterproof qualities. The results of these tests were absolutely conclusive. We use helium because this gas has an infinitely greater penetration than either water or air. The helium molecule is thirteen times smaller than a molecule of air, so that if a watch is helium-proof, that is a guarantee of absolute waterproofness.
Therefore, the use of a helium leak detector amounts to a virtual guarantee for the 600.
Helium leak detector
- the helium leak detector checks on waterproofness.
- helium penetrates across a constant magnetic field, checked by a mass spectrometer.
- a pressure-reducing manometer makes observation possible to 100 atmospheres (3,000 ft)
- even the most minute leak can be charted.
Let us put it this way; if a Seamaster 600 was tested to the equivalent of 1,800 feet, it would take 1,200 years to fill with helium !
Testing to 3,000 ft a watch which will not be used at more than 1,800 gives a margin of safety which illustrates our conscientious, professional approach, and which will be of great value in our advertising.
We should mention here that the depth of 1,800 ft could only be reached in a bathyscape, with a helium atmosphere. Outside a bathyscape, for amateur or semi-professional divers the limit is 270 ft, which highlights the outstanding waterproofness of the 600.
The case is mono-bloc, of special steel, ultra-resistant to shock and salt water corrosion. The back is grooved, so as not to slip on the wrist. The design of the case, with a promontory to protect the crown, gives the watch a kind of functional beauty. The red push- piece is an indication of its advanced techniques.
The crystal is of mineral glass, chemically tempered by a treatment which ensures the best possible distribution of the hard coating, and improves its stability. The glass is anti-reflective and anti-abrasive. The crystal is surrounded by a super-compressed “O’* ring, so that the pressure exerted on the joint is always greater than the hydrostatic pressure. The case and crystal are thus hermetically sealed against any infiltration.
The crown has three positions : for winding, setting the time and setting the date. During this last, the movement stops, so the hands can be set to the second. Unlike ordinary watches, the crown is placed at 9 o’clock, thus allowing the wrist greater freedom of movement. It is built into the case so that there is no risk of snagging. The crown is locked by a safety device, and a patented twin- lock system assures it of perfect waterproofness. The turning bezel, graduated from 0 to 60, is protected by a locking system governed by the red push-button. The graduations and numerals of the bezel are highly luminous, for greater safety. The bezel has a triangular guide mark, which is set opposite the minute hand at the start of a dive. Thus elapsed time can be quickly and easily read off.
The movement. For the Seamaster 600 we have adopted the calibre 1000. This high-frequency, self-winding movement is eminently suitable for a diving watch. It gives the diver additional security, as he does not have to remember to wind the watch.
The calendar has an instant corrector, and the date changes automatically.
High luminosity. The bezel, hands and dial are treated with tritium for greater luminosity at depth. The oversized minute hand adds to legibility, and the bezel is outside the watch, to leave the dial free. Confusion between the bezel and the minute markings on the dial is impossible.
Ultra-durable bracelet. After intensive research, we chose a truly exceptional material for the bracelet : Isofrane. This synthetic material has unique physical and chemical characteristics. It is resistant to tearing, deterioration, abrasion, temperature fluctuation and corrosion. It keeps its shape, does not cause allergies, and is very light. It can easily be delivered in larger sizes, when the watch is to be worn over a diving suit.
A NEW EMPIRE
The Seamaster 600 is the surest watch for the men who work on the seabed. Already it has a great reputation. Soon it will be talked about even more, like the Speedmaster, and will profit from the fame of the whole Seamaster range.
Naturally, the number of buyers who are real professionals will be small; but the potential of the watch among amateurs is enormous. Like the Speedmaster, it will benefit from the exploits associated with it, and like the Speedmaster it will be worn by numbers of people who do not at all need an instrument watch. These considerations seem to us to justify an initial manufacture of 4,500 watches.
The Seamaster 600 is a lead product which fits perfectly into our general policy; that of leading every field of timekeeping.After the heights of space, we are about to conquer a new empire; that of the deeps.*Source original press release from the 1970's