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Old 05-14-2007, 07:14 AM   #13
MNBoxster
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Join Date: Sep 2005
Location: Minneapolis/St. Paul, Minnesota, USA
Posts: 3,308
Quote:
Originally Posted by dmcutter
Now I'm not one to engage in on line bashing, but in this case I feel compelled to weigh in. Jim, you have opened your mouth, clearly, without knowing what you are talking about in this particular case. The chrono in question is made by Eterna, an excellent watch company (surely you're familiar with their COSC Kon Tiki dive watch) using a Valjoux 7750 movement. The Valjoux is used by most of the high end makers for their chronos except for the rare few with an in house movement. I doubt you will find a chrono with a saphire crystal, Valjoux movement, and solid steel bracelet with solid end links for a couple hundred dollars.

Hi,

No sir, I beg to disagree. The Valjoux 7750 Engine was first produced in 1974 as an alternative to the expensive Auto Winding movements available at the time.

It is an economy Engine designed to be cheaply manufactured to allow Fine and Luxury Watchmakers to produce lines in the mid-priced range and thereby increase their Market breadth. It substitutes many wedges, rather than traditional precision screws, and the packaging of many component groups onto large plates to help it achieve this ease of manufacture. But, keep in mind that the sole purpose of it's creation was to be cheaper to produce. It's a good, though not the best movement available in it's price range - compromises were incorporated into the design.

It is not made by Eterna, but by Valjoux SA. Valjoux offers the 7750 Engine in 3 distinct levels of quality and sophistication - the Elaboré, Top, and Chronomètre. The Porsche Design watch uses the Elabore' movement, the most basic of the 7750 Engines. It has also been versatile enough to have several variants produced from the same basic design - the 7760 (Manual Wind w/Date), the 7751 and 7761 (Manual Wind w/ Moon Phase and Date), 7758 (Manual Wind w/ Moon Phase) and the 7765 (Manual Wind w/o 12-Hour Counter).

Prior to the 1950's, chronometres were not extremely accurate as they beat in the 18,000 BPH (Beats per Hour or every 0.2 seconds) (or VPH in the case of a Quartz Engine) . To improve accuracy, it was known that this BPH needed to be increased. Steadily, through the 1960's, BPH increased until Zenith produced the first Engine to achieve 36,000 BPH in 1969. The Valjoux 7750 has a BPH of only 28,000, repectable, but certainly not leading edge.

Also, the 7750 is the bain of most watch repairers - it is very difficult to repair. Major portions of the movement are mounted on large plates rather than each having it own distinctive mounting. This means that to clean/adjust one part, you're disconnecting several adjacent pieces, which now have to be re-aligned and set along with the selected part. This also makes them very expensive to repair - sometimes upwards of 50-75% of the Purchase Price of the watch - hardly an outstanding feature.

The Kon-Tiki, while a good watch, is far from the finest example of the Watchmakers art. It was a commemorative put out by Eterna in 1974 (27 years after Thor Hyerdahl's famed voyage - he never wore one). Heyerdahl wore an Eterna with the Eterna-matic engine, a rotor-based engine (produced in-house) running on Ball Bearings - 5 to be precise - an Eterna trademark. He wore this watch because Eterna was a major undewriter of his expedition.

Also, Eterna used the 7750 only in it's Kon Tiki. It usually used ETA Engines produced by ETA S.A., which it spunoff in the early 1930's from Eterna S.A. . ETA makes some fine engines which are used by vitually every large Watchmaker in Switzerland.

Eterna S.A. was purchased by Ferdinand Alexander Porsche in the mid-'90s. 'Butzi', Ferdi's Grandson, was in the design studio at Porsche when the 911 was originally penned and is said to have contributed greatly to the basic design. He left Porsche AG and founded Porsche Design in 1973, a completely separate company. Their first product was a chronograph made by Orfina and used the Valjoux 7750 Engine. Later, this movement was switched to the Lemania 5100 Engine as this was deemed more rugged. Their current chronograph reverted back to the 7750 Engine, but only because it allowed them to meet a price point, not because of any inherent technical superiority, in fact, the movement is now quite dated.

So, it's of little surprise that Eterna and Valjoux combine to produce the Porsche Design Chronometres, not for any particular technical excellence, but as a practical, cost-cutting alternative.

I don't claim be be all-knowing in the field of Fine Watch manufacture, never said I did. But, I'm pretty comfortable that I at least know a little about the subject...

Happy Motoring!... Jim'99

Last edited by MNBoxster; 05-14-2007 at 09:12 AM.
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