Jaeger-LeCoultre

While reading the title of this article, you may think that it may be a bit too technical, or abstract. In fact, the balance wheel and the escapement are among the most important parts of our beloved watches. Indeed, they are THE sine qua non condition of...  

Hello amanico You had me with the dis-assembly photos. So many things effect the accuracy of beloved timekeepers. Kind regards Anthony

.. to better look behind ! For me indeed quite instructive - have bookmarked this one ! One Q, pls : what are the extremes for the temperatures tested ( let's say for the 1000 hrs) ? Fluids & oils may change their viscosity, but maybe that occurs already ... 

... Post. The insight you provide makes us all appreciate these examples of living art that much more. Best, My Friend! - Scott

How old is it? And by the way I like technical reports, it's good to know what's inside. Thanks, Constantin

That it became Cal 899 in 2002. I am not at home, so my answer is from memory. Best, Tudor. Nicolas

I was browsing on the internet and stumbled over an article about accuracy and this JLC 899 was amongst four praised ones for great accuracy. What I have learned today, again, is that accuracy is depending on everything in a watch to achieve a smooth tran... 

Precision, more than accuracy, dépends on the owner's lifestyle. A Watch is accurate if it looses or gains 20 secs a day, if it is regular. A Watch is precise when it is within the choronemetric tolérances. That is the difference I make. And yes, you are ... 

... and cross read it only an will read the full article tomorrow: it was "even" an ETA 2824 from Tissot that ranked super high :-)! Many thanks for the research tip! Moritz

A tractor, reliable and accurate. Best, Nicolas

I knew of the qualities from the 2824 and the 2892 and that it is widely used in the watch world. But to read how good the 2824 was in the contest is really cool! Another, of topic movement, I came across today is the Buren calibre 82. With 36.000 beats p... 

" Snobbed " while they have some excellent horological qualities. Now, there is one thing to add, while we are at it. The outcome, in these Chronometry contests ALSO dépends on the talent of the watchmaker who finely adjusts the movements. Of course, a ba... 

And let me end on a final note: the other two praised movements, next to JLC 889 and ETA 2892, were Rolex 31xx and ETA's Valjoux 7750. All four are for themselves a primus inter pares for the knowledgeable watch fan and my todays studies just confirmed it... 

That is why I am always laughting when I sometimes read " Well, this is too bad it is only an ETA 28xx or 77xx " and so on... I rarely read that people complao about Rolex movements... Funny, isn't it? I didn't read that people didn't like the 899, tough.... 

I love it to care about these details and about these core diciplines of watchmaking. For those who would like to dig a little deeper: This post reminds me about an article that Jaw wrote about the Autotractor movement cal 97x in 2004. It can be found her... 

... well written and explained for someone with non technical knowledge like me. I always wonder at the accuracy of these little precision machines inside our beloved watches. Your article explains beautifully and I can´t stop viewing with awe these littl... 

To make something quite tough simple. No need to say that I did loose notion of time, while I was given these explanations. Tha,ks for your input and kind words, Abel. Un abrazo, amigo. Nicolas

Thank you for sharing these photos and insights! :) Very interesting and appreciated! Best, my friend Blomman

Almost in the same time... ;) Thanks for your kind words, Blomman. Nicolas

Thank you Nicolas for a wonderful post. I have one question for you which hopefully you can help me to understand. How is that a watch can be adjusted in 5 positions, as well as adjusted for temperature s (plural, as it states on the plate of the JLC move... 

If Under one specifci temperature or position, it doesn't work propelry ( ie you have a loss of amplitude, for example ) you have to re work on it. If the movement works correctly Under different températures and positions, there are chances that, in the ... 

22° Celsius, then 4°, then 40°. Best, Nicolas

Wearing my JLC Master circa 2011, for the Far East. Some dial differences, mainly layout and case dimensions. Otherwise the same. The cal. 899. I find it is running approximately +6 to 7 seconds per day. Nothing drastic and not sending it off to Texas for... 

You can always ask to make it run slower. Best, Nicolas

but I love the accuracy on my MGUT Date! -Dean

I have a cal. 899 in muy Master Control with date. The only difference is that JLC manufactured this version, dial layout and case size, 37 1/2 dia., solely for its Oriental markets. Mine dates from 2011. I find that it keeps great and consistent time at ... 

My wife is about to gift me the Cartier Tank MC and I told her so hold off a day or two so that I can consider the JLC's Master Control Date. I have always admire JLC as a movement maker and won't mind adding them to my collection. Can you please share yo... 

If the date is not important to you, then the MUT 34, 38 or 39 mm is the one to go for. You will add a big touh of class and elegance. Best, Nicolas

Also, my apologies if Im taking up too much of your time

Still you can quite easily hunt a steel MUT 38. Best, Nicolas

and I will go looking for...

Excellent article. Owning a Masterpiece I can attest to what was stated.