AP Royal Oak Perpetual Calendar Date Change

ED209 · 2015-03-08T17:04:45Z

Explore the intricate date change mechanism of the Audemars Piguet Royal Oak Perpetual Calendar. Collectors share experiences on its midnight transition and mechanical precision.

ED209

WPS member · Audemars Piguet forum

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ED209 initiates a community discussion to compare the performance of Audemars Piguet Royal Oak Perpetual Calendars, specifically focusing on the date change mechanism at the end of February. He meticulously documents his own watch's transition, inviting other owners to share their experiences with this intricate complication.

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There's been quite a few posts recently from fellow PuristS with their Audemars Piguet Royal Oak Perpetual Calendar, like fastback1967 (Please click here); and dr.kol (Please click here); and ciaca (Please click here); and another openworked PC from urinosuke (Please click here). It's great to see these AP's and with the recent change to March 1st, I'm curious to compare my RO Perpetual Calender's performance with others. Over the past few years I've been posting my experiences with the date change and my AP has done extremely well. My watch has changed over to the 1st at midnight. So has everyone experience the same thing? Or is there a delay in the perpetual calendar mechanism where it changes over a few hours later? Please share your thoughts and experiences in this post.

For me I was expecting the same performance as before. My AP RO 25829ST is an openworked perpetual calendar that I wear almost daily. Here's a pic on February 28th from my office right before lunch time.

When my AP is off my wrist it spends time in the watch winder. It was a unusual day in Southern California on Saturday where it was raining heavily during the weekend. So I stayed at home while my AP is getting ready for the date change. Here's a pic in the AP watch winder.

I made a quick setup on my coffee table while watching TV. The Royal Oak book and a micro fiber cleaning cloth for a simple photo shoot. By 9:45pm the subdial with the date has already started moving and transitioned over to the 29th.

My goal was to take a picture at 15 minute or so intervals. To be honest I was binge watching the new season 3 episodes of 'House of Cards' on NetFlix, so sometimes it was every 20 minutes LOL.

By 10:23pm the date kept moving closer and had already changed to the 30th. I compared this to my post from last year and my watch was very consistent with this.

At 10:45pm the date barely moved. The other subdials remained the same showing Saturday and February.

And similar to last year things start to happen on the other subdials when I past 11:00pm.

One interesting thing was that the moon display at the 6 o'clock subdial was almost at full moon. Last year my watch was showing mostly stars and a dark night.

Around 11:45pm the day subdial started transition over to Sunday while the date was a hair past the 31st.

From past experience a lot more happens within ten minutes to midnight.

As usual for my watch, the month was still showing February but I was not worried because I was very confident that it would move over at midnight.

Getting closer....

I like having the watch on my wrist and seeing the changeover to March 1st. This year I almost missed it because I was looking at the movement from the transparent caseback. IMO the dial looks great from the front but the view of the skeletonized 2120/2802 movement is really stunning.

I think next year I'll have to get a go-pro and do a time lapsed video to show the changeover. But maybe not because I really enjoy having my AP on my wrist to see the calendar change.

So I'm happy to report that my AP Royal Oak Perpetual Calendar has performed well. Anyone else share their experiences with their Royal Oaks?

Regards,
ED-209

Key Points from the Discussion

The AP perpetual calendar module (like the 2800/2802) typically begins its date change sequence around 10:00 p.m., with the date, day, and month indicators updating sequentially and completing just after midnight.
The mechanical programming of a perpetual calendar movement to accurately handle date changes, including leap years, is a marvel of horological engineering.
Some AP perpetual calendars exhibit an almost instantaneous date jump close to or right after midnight, indicating variations in the mechanism's behavior.
The discussion highlights a past PuristS Perpetual GTG where various perpetual calendars were observed, with some performing the changeover quickly and others taking longer.
A community Google Hangout for perpetual calendar owners is suggested to collectively observe and discuss the date change, fostering shared experiences.
The question is raised whether a slight delay in the date change, not occurring precisely at midnight, would bother an owner.

The Discussion

JerryW

Mar 8, 2015

I was going to watch mine

but I forgot. Next year we should have a PuristS all perpetual google hangout. Thanks for your photos. Best, JerryW

ED209

Mar 8, 2015

That is a great idea... and a question

hmmm, a PuristS all perpetual google hangout would be really cool. Great idea! So would it bother you if your AP did or didn't change exactly at midnight? Regards, ED-209

fastback1967

Mar 9, 2015

Same for me

I forgot also ! Shame on me +1 I agree to have a "Leap Year GTG .... in Paris e.g. " :-D

ED209

Mar 9, 2015

LOL there's always next year

:) Will be cool to have a virtual leap year GTG! Regards, ED-209

SALMANPK

Mar 8, 2015

Beautiful Piece...

and I really enjoyed your report on the date change, it is quite amazing when you think about how they mechanically programmed the movement to know its February and the date change should go to the 1st. Btw wasn't season 3 a lot tamer than the previous 2? I binge watched it the day it came out and although it was good but I was expecting it to be more than good. Did you watch the UK version? House of Cards, To Play the King and The Final Cut were really amazing. S

ED209

Mar 8, 2015

The pepetual calendar movement

Thanks for the kind words Salman. I agree, it's amazing to me how a bunch of small little gears and springs are able to calculate the date change and leap year. It's really cool. I have the UK version up next on my netflix queue and will try to watch it over the next few weekends. Haven't seen the other two but will have to look for it, thanks for the recommendations. Regards, ED-209