Re: Titanium cases

Jack Denver wrote:

We know that even sapphire crystals which as you point out are much harder than even PVD coatings, get scratched occassionally. Also, the hardness of a coating is not the end of the story -watches not only get scratched but also get knocked and dented. A hard coating will not protect a soft substrate against these kind of impacts. Or else you could put a PVD coating over plastic or brass and achieve results equal to hard metals.

You could, indeed, providing you use a plastic material that would stand the temparatures achieved in the arc welding process. I assume that some special carbon-fibre plastics such as used by Glock, Heckler&Koch and other firearms manufacturers in the production of handgun frames might be suitable as they can stand temparatures up to 400 degrees Celsius without deformation. OTOH, such special plastics are more expensive than titanium and certainly look nasty in comparison.


It seems to me that there are really two good approaches to keeping a case "like new". One is to use an ultra-hard material such as corundum - the Rado approach . Not a coating but a solid hard material. However, this material limits what you can do with case shape and can be expensive and if you do somehow succeed in scratching the case anyway ( your wife's diamond ring scratches against it - a not too far fetched scenario) it may be hard to restore.

Well, the surface of a Rado V10k is exactly as hard as diamond - hence the name V10k (= 10,000 Vickers). They achieve this extremely hard surface by growing/"breeding" a synthetic diamond crystal structure on the watch case and crystal surface.


The other alternative is to start out with a material that is hard enough to resist most scratches but when the inevitable scratches do occur is easily polished back to original appearance. The material that is best in this category is IMHO plain old boring uncoated stainless steel.

Stainless steel is a very good compromise between sufficient hardness, toughness and protection of the movement against all kinds of external influences including shocks and magnetism.
It is also quite inexpensive to buy, easy to process (at least compared to PVD layering, synthetic crystal breeding and the like) and easy to buff or polish. Last not least, it's an optically quite attractive material.

Its physical properties, ease of processing and good looks make stainless steel the most versatile watch case and bracelet material.

Best regards,
OP
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