Accidentally change date during forbidden hours

Hello all,

I've just accidentally changed the date during these 'forbidden time' (between 20:00 to 03:00) on my Portofino 5101. As this is a new calibre and does not have much info on it, I had to refer back to a posting in another forum to understand what sort of damage which I might have done.

forums.watchuseek.com/f350/experts-5001-movement-808337.html

I’m assuming that the 59000 calibre in the Portofino 8 days is after all based on the 50000 and it probably has the similar semi-instantaneous "clam-spring" wheel as the date wheel starts moving at approx 23:15.

Horror struck me when I made this mistake (as I was travelling and changing the time and date) and I stayed up to observe the change of date right before midnight. The date still changed normally at 23:59:30 (usually at 00:00:30, which I think is still within the tolerance of this calibre, just the minor interplay between the many teeth of the wheels). This is still more accurate as compared to my new Portuguese 7 days which changes at approximately 00:01:00. This somewhat proves one of the posting in the link above to be correct.
I'm still observing it tonight again, just to be sure.

I also refer to previous posting and an in-depth explanation by Leo on the date changing system to understand this better.

www.iwc.com/forum/en/discussion/61639/?page=2

However, does this mean that the caliber of 50000 with the semi-instantaneous date wheel change is somewhat less prone to damage as compared to other caliber type when accidentally changed the dates during the forbidden hours?

A sensible assumption is to follow the rule and not take any risk, but I’d like to hear from the experts here as this is another less-discussed trait of a well-designed caliber that have taken this into consideration of knucklehead users like me that makes occasional mistakes like these.

Cheers,

Sorry to interrupt your thread but I have a related question.

If your watch is not in use for a few days and it runs out of juice in the time period mentioned when you shouldn't adjust the date what do you do? Wind it up and let it run until it is past that specific time period and then adjust the date??

Cheers,

Jarrod

Vincent, I hope your one is ok with no damage.

Hi WAIKATO7,

You can anytime adjust the time. (forward)

Even far enough to move the date forward?

Yes gentlemen,
You can always adjust time forward to change date. It's only the quick date adjustment that must not be used during the forbidden time.

Thank you for this information, i was not aware you can not change the date yourself between certain hours . Is this between 23.00 and 01.00 hours ? and does this also include the portuguese 5001 ref ?

Ps my date changes exactly at 00.00 and within less than a second, just snap changes. So i assume the `danger period is also less than a few hours ?

To answer about how long is "danger period" is best to answer how it works:
I try to explain it on picture of ETA 2892A2.

In green circle we can see date corrector- which is operated by crown in position 1.
In red circle is "thing" (i do not know correct name) on date indicator driving wheel that changes the date at midnight. However the date change appears to be quick, this "thing" is still near the date indicator.
And if the date would be manually changed in this period (23:00- 1:00) date indicator is pushed forward by the date corrector and then date indicator will collide with "thing".

Thanks Matej09, that is very clear now.

Hi Vincent,
As Michael has said 'the 59000 series movements are not based on the 50000 Calibres'. In fact they are Very different in design and layout. But fortunately for you, the only parts the 2 models have exactly in common just happen to be the fantastically designed date wheels(as imaged in my previous post that you linked to) along with the robust stem & it's operating components.
The design has been proven to offer extra security against 'forbidden zone' mistakes but can not be taken as an eliminator of the 'forbidden zone' rule.

When driving we still use the brakes, even though we have seat-belts and air-bags...

Leo

Leo, thank you for the explanation. Again, glad to know some solid engineering behind every IWC calibre. Makes me love it even more now!

Cheers!