Ordinarily, the use of temperature-related terms in the context of watches refers to either “cool,” as in achingly desirable, or “hot,” as in those watches which are metaphorically on fire in the shops or auction sales rooms. However, while all Urwerks are cool and the Rolex ‘Paul Newman’ is hot, this month’s missive is about actual coldness – which you might think has precious little to do with a watch’s well-being.
Er, actually, no. Temperature means as much to watches as do the fights against magnetism and shock. On the most fundamental level, coldness affects the essential lubricants that keep your mechanical watch running smoothly. (If you happen to wear a watch with a battery, extreme cold can affect its performance, too.) But, as you’re wisely surmising, as you wear a watch on your wrist, in contact with your body – surely the heat you generate prevents this from happening?
True, in quotidian usage. But what about mountaineers, divers and others wearing watches in the extreme cold, often over their sleeve?
Severe changes in temperature cause metals to expand and contract, even if on an invisible-to-the-eye, molecular level, and this affects timekeeping. That’s why the industry is in love with silicon parts, which are virtually immune to temperature, and why the most popular and successful metal mainsprings are made of alloys which retain elasticity and remain constant.
Leaving aside the heat from your wrist, there are exceptional timepieces which can withstand the cold with better-than-normal efficacy. And, no, I cannot think of a single dress watch with snap-back case that qualifies: you do not wear your ultra-thin timepiece while scaling Everest. Which nicely brings us to Rolex, Smiths and the like.
While the original Rolex Explorer was basically a regular Oyster, it did possess what was, at the time, one of the toughest cases on the market, its water-resistance helping in no small measure to keep out the elements. Smiths, too, produced watches which were put to the same mountain-conquering test. Longines WWW watches were used on arctic expeditions, Eterna’s were worn on the legendary Kon-Tiki adventure crossing the Pacific on a wooden raft – horology is rich with examples of this nature.
Then there’s space travel. In a tale recounted too often to repeat here, those of you already au fait with the Omega Speedmaster Professional will know that it beat all of its rivals for NASA approval for space missions. The original tests, including vibration, corrosion, humidity, heat extremes and other trials, also included one for survival at -18°C for four hours, which in technical terms is frikkin’ cold.
Scuba diving is more likely to involve some of you than space travel, so it’s worth remembering that the temperature concerns for a mechanical diving watch, though less challenging than those applied to the Speedy, also guarantee imperviousness to the cold. The EU considers ‘cold-water diving’ to be when the water temperature is equal to or below 6°C. This provides you with a guide for buying a watch to withstand the cold, especially should you be a vampire or other individual with a body temperature below 37°C.
Hence, certified professional diving watches from Rolex, Seiko, Doxa, IWC, Breitling or others of that level will survive any arctic or Antarctic jaunt. But if you’re really worried, look to Ball. This company ensures the survivability of its toughest models through the use of specially-blended oils that “expand the operating temperature range from -40°C to 60°C (-40 to 140°F).” If you need anything outside of that, then you’re too cool for school. Sorry.