can a eta Elaboré be regulated to cosc ?

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can a eta Elaboré be regulated to cosc ?

Post by jayrob84 »

can the eta Elaboré in the c60 be regulated to cosc

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Re: can a eta Elaboré be regulated to cosc ?

Post by Amor Vincit Omnia »

COSC is a very specific thing; it refers to a test on the movement carried out by the Swiss watchmaking industry. A certificate is issued for movements that pass.

However, it does seem perfectly possible to regulate a slightly "lower grade" movement to the sort of accuracy required by COSC.

Hope that makes sense.
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Re: can a eta Elaboré be regulated to cosc ?

Post by Hedgehogger »

To add to what Steve said,

From ... 20to%20the:
To have a watch pass the certification, the movement must be sent to one of the COSC labs where it immediately goes through the following: tests the numbers engraved on the movement (in relation to the list supplied by the applicant), the movement is placed in a 5-slot clasp, the movement is wound according to the brand’s supplied guidelines, and the parts are placed in a temperature controlled enclosure for 12 hours at exactly 73.4°F (23°C). Then, over the next 15 days, the parts of the wristwatch go through daily tests. Each day, the clocks and watches are measured and reassembled. At the end of that time period, the wristwatches are judged by seven different criteria: average daily rate, mean variation in rate, greatest variation in rate, the difference in rates in horizontal and vertical position, largest variation in rate, and variation in rate depending on temperature and rate resumption. You can see the exact specifics below. If the watch passes these guidelines, it is officially awarded the certification.
I suspect getting it certified would cost more than the watch?

But does your question really mean, "Can you regulate a non-COSC certified watch to fit within the COSC test rates? Maybe. But no guarantee.

I've had some cheap movements that I regulated that will consistently maintain +/- 2 seconds a day. And I've had some that I regulate to +/- 4 seconds today, but then tomorrow they are +16 seconds, the next day -2. Or maybe I can get it to -3 seconds when it is laying flat, only to find it goes to -13 when placed on its side.

That being said, the ETA movements are very good, and usually not like the cheap movements I'm referring to. I've only regulated about a half a dozen ETA movements (2824 and 6497) and they have all easily been regulatable (is that a word?) to +/- 4sec a day and would hold that despite the position and over time. None of those were COSC certified. (Although the two COSC certified watches I do own both keep excellent time).

Here FYI are the COSC criteria:


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Re: can a eta Elaboré be regulated to cosc ?

Post by richtel »

I think the point is that just about any movement sat statically on a bench can be regulated so that for the time it is being worked on, it appears to keep time to a precision of -4/+6 spd. The problem is that all watches are susceptible to positional variations, temperature fluctuations and power reserve depletion.

Keeping good time across all those challenges requires a lot of watchmaking know-how and where a movement manufacturer has a range of specifications for a particular model (eg standard, elabore, top, chronometer), there are likely to be be subtle incremental enhancements in the components and quality control to counter those challenges.

While a given movement after careful regulation may appear really accurate, it might not be as good as a true premium movement across all of those factors. It might also appear to 'drift off' over time. There's a degree of luck involved- so some elabore movements might be 'better' than others of exactly the same type, but there's no denying that you're more likely to have a watch which is accurate within all enviromnents if it has been specifically built to the task of acheiving and maintaining chronometer status.

At the end of the day you probably pay a lot more for a COSC certified watch. Whether paying that premium for a certified level of performance versus what many might deem as 'perfectly acceptable' is down to personal judgement.

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Re: can a eta Elaboré be regulated to cosc ?

Post by It'sAliveJim »

Any watch can be regulated to keep time within COSC spec, but how long it stays in spec depends on the movement.

An ETA Elaboré should have no trouble staying within the spec for years.

When I bought the Doxa 50th Anniversary 300 COSC it was running at +10 after four days of daily wear so clearly not in spec. Doxa posted this on WUS: ... 24642.html

Three years later and mine runs at a consistent +3 so it seems there was a settling in period.
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