Horological Meandering

A common topic on watch related websites is the Water Resistance ratings of various watches. The common element in achieving WR is the humble O-ring - whether the watch is a 30m rated dress watch, a 610m Rolex Sea Dweller (see Dr Strong's recent post) or ...  

but let's say 3 highes and 5 lowest. Best, Kari

One Highest and Four lowest. My reasoning is that the more the O ring can be compressed the more it will adapt to its environment and seal properly. My model behind it is that an O ring in a watch is very slim and compressable. Regards, Yves

1 is lowest since it's big and wobbly. 3 is highest since it's thick and small.

... I would have thought it was easy, but then I started to imagine some of the variables. Thickness, compressibility, surface area exposed to the pressure, and who knows what else a real engineer might think of. So I will guess 3, 1, 2, 4, 5. Look forwar... 

..is one of those things where it's so simple, yet you get into the detail you just start doubting! Let's take a crown o-ring for that 200m watch. Where do we start? Well, unless we're happy with a 15mm diameter crown, we're restricted to small <5mm OD o-... 

2 of the O-rings are from a watch. 2 of the O-rings are from Scuba equipment. 1 of the O-rings is from an Engine.

Number 5 is from the Egiziano? A

First off, thanks to those who took the plunge on such a vague quiz. This was a bit of a dishonest question. As I alluded, there are a plethora of factors that contribute to the pressure resistance of an o-ringed joint. However I tried to find as diverse ...  

nt

Thanks for the quiz and the education. A lot of fun. O-rings are forever associated in my mind with the Shuttle Challenger disaster. When o-rings fail, they can do so in spectacular and disastrous ways. Andrew

...dipping an o-ring into the glass of ice-water to demonstrate the change in o-ring response at lower temps. There's a humungous amount of info on the Challenger disaster, but as I understand it, the o-ring failure was caused by: An uneven groove depth a...  

honest guv'nor i did, i knew them all dishonestly knowledgable Graham

....it's already December... Cheers, pplater.

i'm going into a state of hibernation at the moment. 2 more inches of snow last night. surprisingly Wales has had it easy so far. scotland and the east all the way down to Gatwick airport is in chaos. ho hum, 3 years on the trot we've had bad snow so best... 

I'm getting round to it this weekend Hope it's OK for next week in sunny London..!! See you soon.

snowman?? of course i'm not building a snowman and for several reasons. 1. i have no kids to make happy (and neither have you you child) 2. its cold outside and warm indoors. 3. i'd miss all the exciting daytime TV while i was building it. 3. i like the l... 

Thought you were being shy. I have some other ideas that I'll make sure you get the chance to guess at...