The general definition of chronometer is a very much accurate timepiece, do you think so? But how accurate it is actually is? Well, the chronometer as we know it today grew out of the pursuit of a solution to the problem of determining longitude at sea. It turns out that the solution was to know when it was noon at your location on the open ocean and, simultaneously finding what time it was in Greenwich, England. Use simple arithmetic to pick out the time difference and you could find how far west or east you were.
We won’t go into the technical details of what John Harrison did to design a cheap replica watch perfect enough to ultimately won the Longitude Prize, but win it he did. Basically, a movement that’s been certified by COSC and achieved chronometer status is accurate to -4/+6 seconds per day. But there’s a little more to it than that.
The testing it takes to achieve a COSC certificate is based on ISO standard 3159. A movement is tested over fifteen days, in five positions, at three different temperatures. Measurements are made each day and are compared to two atomic clocks. The standards for achieving a chronometer certificate are as follows:
And to reach this kind of performance, there are lots of physical effects and circumstances that need to be mitigated, avoided, or overcome, about individual components and their assembly.
Temperature effects include viscosity changes in lubricants and thermal growth or shrinkage of parts.
The dimensions of each component need to be controlled. Design tolerances – the degree to which each piece part is dimensionally identical to its siblings in a manufacturing lot, and to the original design dimensions – must be maintained. This also relates to how each component mates to the parts it interacts with.
And components that are not intended to directly mutual-effected or must never inadvertently touch each other. And it should go without saying that there can’t be any foreign matter floating around the movement.
After all that is properly accounted for, there are still going to be infinitesimal differences in the build of each movement. These are due both to infinitesimal differences in the individual components used to build each movement, and minute differences in alignments – even with locating pins and shoulders.
These small differences are enough to cause differences in how each movement runs before adjusting. Therefore, a watchmaker is required to make those final adjustments and bring the replica watches movement into spec so it can pass the COSC tests. That’s where – surprise! – “Adjusted in five positions” originated from on fake Rolex movements.
Month: July 2018
Noticeable Things to Keep in Mind When Choosing a Rolex Replica
Rolex watches are always one of the most popular watch brands almost for all the people, and in some instances, even appreciate throughout the years – despite receiving daily use from their owners. While the Rolex replica watches can keep their value far better than the huge majority of timepieces from other manufacturers, not all Rolex watches possess the combination of traits that permit them to appreciate and serve as blue-chip investments. 
While modern Rolex watches are packed with all of the newest technologies and materials, it is the vintage market where all of the record-breaking valuations occur. Rolex watches that are still in production have a finite limit for how much their values can increase, since a brand-new example of the watch can always be secured directly through an authorized dealer at its regular MSRP retail price.
Much like antiques, vintage cheap replica watches frequently derive their value from the fact that they are not in production anymore, and the surviving examples still in existence are all that there will ever be. What’s more, since many of the older Rolex watches were treated roughly and without the same degree of care and consideration that modern Rolex watches experience, many of them were lost or destroyed all over the years, further limiting the number of surviving examples in existence today.
Not every vintage Rolex watch has the potential to be worth more than a new one simply because it is old. Certain lines of fake Rolex watches are more passionately collected than others and can have much greater opportunities for appreciating. While the Rolex Datejust and President are among some of the most iconic and recognizable watches in the world, it is Rolex’s professional watch collections that generally receive the most attention and the highest bids from serious collectors.
For several Rolex’s contemporary sports/professional watches, public demand far exceeds annual production numbers for the given watch, resulting in waitlists for certain models that can sometimes reach up to several years in length. Within the past several years, we have seen this happen for several of Rolex’s stainless steel sport/professional watches, where long waitlists at authorized dealers drive prices in the pre-owned market above retail prices for brand-new examples from authorized dealers.
Much like the luxury Rolex Daytona, the all-green version of the Submariner quickly grew in popularity, and soon experienced a demand that exceeded the number of “Hulk” Submariner watches that Rolex manufactured each year. A third, contemporary, stainless steel Rolex sport/professional model that has experienced appreciation in a relatively short amount of time is the replica Rolex “Batman” GMT-Master II.