Hello, I recently got my first ever chronograph, the Speedmaster Moonwatch. I have noticed a few things with the chronograph recorders and I was wondering if they are normal?

1. The minute recorder moves to the next marker when the second recorder is at approximately 59 sec.
2. The hour recorder hits the 1 hour marker when the minute recorder only reached 57 minutes.

Please let me know if this is a normal inaccuracy of the 1861 movement or does it need to be sent in under warranty for a recalibration?

Thanks!

 

My minute recorder starts to move at 58 seconds, but doesn't click to the minute tick mark until 59.67 seconds. My hour recorder slowly progresses to the next tick mark and at 57 minutes an 30 seconds, appears to be on the mark (at least to these aging eyes). Fortunately, I don't have too much reason to use a chronograph to time things that run this long, but I admit, it's a little disappointing.

 

There was a big thread on this a few weeks ago, sorry I don't have the time to find it right now. Basic summary is that many people's watches are imprecise in when the counter advances, but it's something which can be made more accurate in servicing.

 

If it's only the counter advance that is affected it shouldn't really matter, no? The chrono sweep hand is what should take more or less exactly a minute.

 

Both of these faults are common, but I am not yet willing to say that they are "normal" and should be accepted. It really depends on the extent of the errors.

The minute recorder flip is controlled by a finger on the chronograph seconds recording wheel. I normally find that these flip right as the central chrono seconds hand passes the 12, like this:

Note that this is an 861, but the 1861 is exactly the same construction as the 861 with regards to the minute recorder flip. The 321 is a different animal, and that one can be precisely adjusted.

I recently had an 1861 in the shop that the minute counter would flip a full second after the seconds chrono hand had passed over the 12 marker. I had some of my own ideas about resolving this, but since Omega's technical guides were silent on any solutions, I decided to email the technical guy and ask some questions. One was is there a tolerance to be applied, because Omega's technical guide just says the minute counter should flip as the hand passes over the 12 mark. I never did get an answer to that question.

My other question was, what adjustment is there for this - the answer to that is officially none. I asked how they handled this situation, and he said that the minute and seconds counter wheel are changed, and they see if that improves things. Not much of a strategy. Since I seem to be reading a lot about this specific problem, over the last year maybe, and I am now seeing modern 1861's come in on occasion with the minute counter not flipping spot on, my guess is that something in the manufacturing tolerances has changed slightly sometime in the recent past.

On the hour counter, there are a few things to consider on that one. First that counter is driven directly from the mainspring barrel, and how fast it moves is not directly tied to the seconds and minute counters. The mechanism that drives the hour counter has a number of friction reliant components in it, so if the amount of friction there is not appropriate, it can cause the counter to not move correctly, or can allow the counter to move under even a small shock. Also how accurately the hand is mounted (which can be difficult to see with the chrono seconds hand in the way when reset) can have an impact on this error. In addition if the hour hand moves when you start the chronograph, which people may not notice, that can cause it to be ahead of the minute recording hand. The hand can move due to magnetism, or excessive/sticky oil on the can and hammer.

If these things bother you, you could always take it in and ask for it to be resolved. The hour counter I think they could certainly improve, but the minute counter flip I'm less sure of. I have now replaced wheels in an effort to improve the minute counter flip, and it did help, and there's a small tweak to a spring that I've found can make a very small difference. I've yet to come up with something that will be 100% though.

Cheers, Al

 

The minute hand on my 2017 Moonwatch flips right around 59 seconds. I only just noticed because I read this thread I don’t really mind though- I can’t imagine opening the watch for this reason; what practical difference does it make?