[Archer]

I'm sure somebody like Archer can give you a much more accurate rundown of the mechanics of it - or try the magic google machine...

You called? ;-)

First off a disclaimer - forget what everyone on an internet watch forum says (in particular those who claim it is a myth), and read the manual that came with your watch, and follow it.

Now with that out of the way, the answer to this question is......it depends.

It depends on the specifics of the calendar mechanism on a specific movement. For example on an ETA 2892 or 2824, the "finger" that trips the date indicator is spring loaded, so although it may cause some resistance when quick setting the date, it's not likely to damage anything if you quick set when the watch is already in the process of changing the date. However, on an ETA 2836, you most certainly will damage something if you force it because the mechanism is totally different.

The ETA 7750 is often cited as having this issue, and yes sometimes damage is done, like on this Tissot chronograph:



Here you can see the finger that drives the date indicator wheel was completely snapped off:



Now there is a safety in this system, but it seems a lot of watchmakers don't know about it so often it's not working properly, and I would not count on it saving you personally.

So for the Omega 2500, which is based on the ETA 2892 and uses the same date mechanism, the finger is spring loaded so the chance of damage from using the quick set during the restricted hours is small. I still would not do it intentionally or anything, but the chances of it actually breaking something is small. Note that the restricted hours usually include time before and after the date change - this is because the finger that flips the date indicator only makes one revolution per 24 hours, and it takes time for the finger to move out of the way after the date has flipped.

Note that one some vintage Omegas, the risk is higher - for example on the Cal. 563, 564, and 565. Since the quick set is done by pulling the crown out to the third position with that act alone flipping the date one day ahead, it's easy to accidently trip the quick set as you are trying to pull the crown out to position 2 to set the hands. The problem was so common that Omega designed a sacrificial part in the date mechanism that would flex and fail before it damaged the date disk.

I'll just reiterate that even if you think you know better because a watch has a specific calendar mechanism that you think is okay to quick set at any time, be aware that manufacturers do sometimes modify the base movement, so referring to an following the instructions in the manual is the right thing to do. Picking a known safe time to adjust the date like 6:30 AM is a good idea.

Hope this helps.

Cheers, Al

 

[Archer]

As long as the date changes normally there's not likely any damage done. For the 7750 example above, of course the date would no longer change as the finger was not there to advance the date indicator.

The 3330 is a modified 7750, so in addition to having a column wheel fitted, co-axial escapement, and moving the minute register around, Omega also changed the way the date works. It has the same type of date driving wheel that the 2892 does (same as your 2500). So instead of a rigid finger like I showed above, the finger is spring loaded - this style look like what you see here:



The red arrow points to the finger that drives the date indicator, and it can collapse into the middle of the wheel under load in the right direction, so again I would not recommend doing so, advancing the date using the corrector would not likely damage anything. This is why I mentioned above that even when you know the base movement, things can be changed, and in this case it's for the better in terms of the date.

Cheers, Al

 

[Archer]

The quick set would no longer function, and the regular date change may be affected as well.

 

[Archer]

After reading all the posts here, would it be correct to say watches with only ETA or modified ETA may potentially have the forbidden period advisement.

Any watch manual with in house movement mention about the forbidden period?

Please check every manual for every "in-house" movement ever made and get back to us with the answer.

 

[Archer]

Ha ha ha. That's a good one. Well.. in the modern world there is a concept called crowd sourcing. Every pertinent person provides their inputs and thus makes the life of information seeker very easy.

I read that as "I can't be bothered to do any actual research, so I'll ask people on a forum and say that's my research." I guess it's the times we live in when everyone expects an answer to everything to be out there for the taking with no work or cost to them...sorry, I digress...

Anyway, I've already given an example of an "in-house" movement that can be damaged by changing the date via the quick set at the wrong time of day - the Cal. 563, 564, and 565 Omegas. The same would apply to the 750 series, and 1010 and 1020 series. In fact I have a 1020 I'm working on right now where the date indicator was damaged this way, and now the date doesn't sit right in the date window because the damaged teeth on it (it's made of plastic) interact with the date jumper in such a way to cause the whole thing to be skewed by a few degrees. The only fix is to replace the date indicator.

Not sure why you keep wanting to tie this back to being just ETA or modified ETA movements, but that's clearly not the case.

Cheers, Al

 

[Archer]

I'm glad you appreciate the information I post, but again the authoritative source is the manual for your watch, so I would encourage people to read the manual and follow it. One issue I see with the premise for your specific interests is what constitutes "modern" and what is "vintage" or "older" in terms of movements. These definitions are not written in stone, and some people consider anything but the very latest generation of movements to be "older" where some don't consider anything made in the 80's or later even being close to "vintage." So is a 2500 movement modern, or older? What about an 1120? People often draw that line in very different places, and as a reminder the Rolex 3135 was first introduced nearly 30 years ago now, and the original 7750 design is older than that.

So when I give an answer, I try to be as complete as I can. You may not care about vintage movements, but there are plenty of others here reading these threads that do. Even though there is a lot less vintage content here than there used to be, there are people still seeking information on those movements as some of the questions asked in this thread attest to.

In your first post you said this:

"Omega: They also mentioned that this concept is not valid for any of their co-axial movements due to their jumping hour hand mechanism."

But clearly not all Omega co-axial movements have the jumping hour hand complication (3330 already discussed in this thread is one example, as is the 2500D), and some Omega movements that are not co-axial have this feature (the Great White GMT and others fitted with the Cal. 1128). There is no one size fits all answer here is the point I made in my first post in this thread.

The assumption that the person has no intention of doing his/her diligence post sourcing the data is not accurate.

Here we will agree to disagree, at least based on the typical posts I see on watch forums like "Here is my watch - tell me about it!" threads, and when people don't answer within an hour or two, the poster is posting again asking why no one has the answers they want to hear.

Yes I might be having a bit of a "grumpy older guy" moment, but it seems to be a given that information on just about anything should be out there with little work required to find it. Now excuse me...I see some kids on my lawn I need to go yell at. ;-)

Cheers, Al

 

[Archer]

This is a bit unclear to me, because it seems to suggest that the restriction does not apply to my calibre (1164), but only to the calibres 1151 and 3606. Am I correct in drawing this conclusion?

No - the restriction applies to the 1664 as well.

Also, I would very much like to know if there is any way for me to see if I have done any damage to the movement, aside from waiting 24 hours to see whether the date changes properly. Is there?

Pull the crown out to the time setting position, and run the minute/hour hands around until the date changes at midnight. If it changes as it should, then likely you are fine.

Cheers, Al

 

[Archer]

It just depends on mechanism. ETA 28... have loading date change which uses spring instead of wheel, therefore its harder or even impossible to break...

For a 2824-2, or 2892A2, you are correct. For a 2836-2, you are very incorrect.

If there's one thing I'll try to get through to people here, read the manual and follow it. If you have questions, contact the maker of the watch.

If in doubt, avoid changing the date between 9 pm, and 3 am.