Okay Gollnick, you asked for it
Straight from International Wristwatch (IWW) #40, 1997, UK edition:
"There are two aspects to Sinn's solution[to the deterioration of movement oil]: the drying capsule and the argon filling. First, a drying capsule was developed which would remove any residual moisture from the inside of the watch. This capsule contains copper sulphate, a hygroscopic compound, meaning that it attracts moisture without becoming liquefied. The capsule is screwed into the lug of the watch and a specially developed membrane allows moisture to pass into the drying capsule while preventing the drying salts from from getting into the watch...[a little blurb on how you can see the capsule]...the watch is filled with argon before it is sealed. This is preferable to a vacuum since air can penetrate even a titanium case by molecular diffusion. Argon is an inert gas which cannot form any compound with the oil in the watch: unlike air, its molecules are too big to diffuse through titanium". Now, why open the watch? Well, perhaps it needs to be regulated or the waterproof seals (o-rings) need replacing or perhaps it may be in need of more serious repair (can you own a car without EVER opening the hood or changing the oil?)
As for Lange...they are a resurrected brand (like MV Agusta, Bugatti etc.) not a completely new brand...while they are not as well known as Patek, they are climbing VERY quickly while Vacheron is on the way down (no offense
).
BTW, another quirk about automatic watches is that they should not be allowed to stop...if you plan to not wear them for several days at a time, you should get a watchwinder.
Finally, I said they should be checked once every few years not once per year.
RL
[This message has been edited by RL (edited 23 September 1999).]