AndrewD
[HoMe Moderator]
12829
Too many years since Physics classes
Thanks Andrew, that’s very helpful.
Does an expansion of 5.4 times imply an increased pressure of 5.4 atmospheres? And in practice the much lower external temperature (minus 40 to 60oC) must reduce this expansion considerably.
I guess that even if a watch is rated to withstand a certain pressure, the design is such that this pressure should come from the outside rather than the inside.
Pressure differences are still the best explanation, Watson.
A
Lenses (Part Three): a shattering experience
I learned first hand why the hesalite lenses used on Omega Speedmaster Pro’s are the preffered material in space. Despite being unaware of any trauma to the sapphire lens of this Zenith Prime, after carefully laying it down in the watchbox the night befor...
Strange
Andrew, Do you have any idea what could have caused such large fractures in your Zenith's sapphire crystal? Is it a function of rapid pressure/temperature changes possibly? I don't know how this could've happened, short of you knocking your watch with sig...
Shattering Experience.
About 8 years ago, I checked some watches in my Luggage. They were in an unpresserized cargo hold on U.S. Air going from L.A. to Charlotte NC. The lens popped out of the case but did not shatter. It was an essentially new ETA 7560 chronograph made by Hebd...
Interesting story, BUCKO …
… If the theory is correct it suggests that the watch is impressively water (and air) tight. Someone with more physics background than me might be able to work out how much the air inside a watch case would expand at 35000 feet, but personally I would be ...
Too many years since Physics classes
Thanks Andrew, that’s very helpful. Does an expansion of 5.4 times imply an increased pressure of 5.4 atmospheres? And in practice the much lower external temperature (minus 40 to 60oC) must reduce this expansion considerably. I guess that even if a watch...
Wouldn't the expanded
...air simply leak out of the case? The pressure gradient in a watchbox in your house is going to be very shallow. Plenty of time to leak out....
No alien abduction theories?
Hi Daos, I don’t recall any anomalous atmospheric conditions that night, or aliens hovering overhead. The kids were already asleep and, as I mentioned, I was not aware of any trauma to the crystal during the day. Hopefully this is a once in a watch-collec...
"They're here."
... or Poltergeist ? As long as they wind up my watches, I don't mind....
Well...a few possibilities...
you hit glass at the right spot even a small blow can cause this... extreme temperature or pressure or frequency...could do it.... you got pissed and threw it... somebody (dear...or not) got pissed at you and tried to hit you with something and blocked it...
All great theories, ppcollector ...
… many of which made me laugh. I do agree that the right blow to a crystal, perhaps if it was under pressure at one point in the mounting, could do this. Just interesting that it did not happen while on my wrist. I guess Daos’ experience with the windshie...
It's hard to tell...
....from the photos, so this may be completely erroneous. But since you cannot recall whacking it on anything, it appears that the installed crystal had too much pre-load around it's perimeter (eg crystal may be marginally oversized). The appearance of th...
Compressive and tensile stress…
… I don’t know what sort of stress that is, but I may be suffering from it! Seriously though, I think you are right. I have been walking around with a ‘time' bomb on my wrist. That’s a very helpful explanation. Andrew
Mystery...
My first thought was that there was some kind of resonance factor, but sounds highly improbable. Very strange, glad all is well. Looks traumatic. Very nice watch.
I'll still rock in the shower...
...(as long as she likes it...whatever! =:^D). However, methinks whether it's sythentic sapphire, rock crystal (a la Marie Antoinette watch by Breguet), Hesalite or whatever, it can crack in many different ways by many different means. Watch (no pun inten...
What about Suction?
I once knew a girl that could suck the chrome off a trailer hitch. Don`t know what she could do to a watch crystal...? BUCKO