Deep inside a Calatrava - preamble
Most of us only experience haute horlogerie through a sapphire case back and while we are promised amazing finishing throughout the whole watch we for obvious reasons can’t verify this for ourselves.
Having acquired a ref 96 from 1943 with an unknown service history I thought it would be a good opportunity to find out exactly how Patek Philippe earned their reputation as well as finding out a bit more about my watch. During my web browsing I came across an amateur watchmaking blog which gave detailed teardowns of the watches he services. A few exchanges of emails later and my watch was scheduled in.
The rest of this post is an edited version of the watchmakers own blog combined with a few of my own thoughts.
I was quite surprised at the findings and it certainly makes me appreciate what goes into a good service.
Part one - external appraisal
It doesn’t get much more exciting for me than this – a Patek Philippe on the bench!
John from Malta sent this watch in for a service, and I’m more than happy to oblige.
In my book, watches don’t get better than this – clean design, great movement, simple, understated, and, most of all, beautiful.
There is quite a big dent on the side of the case at 12:30 – looks like the impact was such that the springbar was pushed well into the case.
[John -I'm not convinced this was the result of an impact as the dent is in an odd place. Perhaps it was due to someone trying to change the strap by levering the springbars
Part two - cracking the back
My master watchmaker, George, agreed to take apart the movement with me. This not only offers me some moral support, but for the forensic work we want to do, it’s so much better to have another person to discuss findings with.
To prevent further damage to the slot, I use a proper case back opener.
Note the little groove in the case at 4:30 – this gives you access so you can lift off the dial without having to take the movement out. I like the thinking behind this feature – it makes my work easier and less risky, and somebody thought about that. For me, this is part of haute horlogerie.
The dial even has its own serial number
Part three - the teardown
I just love how the bridges and cocks form a wave throughout the movement. It also separates the functions out nicely, and makes it easy to see how the movement works. Just stunningly beautiful.
I open the screws on the balance cock that hold the hairspring, slide the regulator pins out of the hairspring and remove the cock. That way, I don’t stress the hairspring in any way.
Looking at the balance, I notice that two of the poising screws have been filed down, and two have washers that were added. This is not something that would be done at the factory, and I interpret this as follows: the mark in the case shows that the movement must have suffered a substantial shock at one point. As the movement doesn’t have shock protected jewel assemblies, this will have broken the balance staff, which was then replaced. After replacing the balance staff, it must have been noticed that the balance wasn’t poised any more, and somebody tried to rectify that.
What strikes me as odd is that the screws that were filed down were left rough and even burred. Also, replacing the balance staff shouldn’t make re-poising the balance necessary, unless something went wrong.
Now a look at the dial side.
Before I proceed further on the top plate, I remove the components of the bottom plate. Note the two cap jewels of the balance and the escape wheel – one is white (escape wheel) and one ruby coloured. Patek would not do that – my guess here is that the cap jewel was damaged when the balance staff broke. Odd though that the new jewel (the white one), was put on the escape wheel, rather than on the balance staff.
Lovely perlage on the bottom plate – this is where the sun doesn’t shine, and only the maker and the likes of me ever get to see this! That’s why I appreciate touches like that even more.
From a conservation point of view, I quite like the white jewel. It gives me that decent hint that something was changed, and leaves a visible trace of work undertaken without damage. If done on purpose, I do agree.
Part four - the wheel train
Even the barrel lid has perlage decoration. Something is odd about the mainspring looking through the lower opening in the lid.
This is pretty shocking … and I know why the impulse pin is knocking the bankings! The mainspring must have broken at one point, and, instead of replacing it, somebody shortened it by one or two turns and bent it back on itself and wedged a piece of broken spring into that bend to form the end that locks it in the barrel. The shortened mainspring will produce too much torque, and the running time of the movement is a lot lower. On top of that, the guy used wheel grease or something similar on the mainspring.
And finally, the bare plate
These are decorations that nobody except the manufacturer and a service watchmaker would ever see. It's an incredible amount of detail with no real functional benefit. Absolutely stunning. This is where precision engineering meets art.
Now some questions...
Great post. Thanks John
I gets my vote for post of the year
I have no idea what I could add to such a nice post so I better shut up
But I really, really, REALLY enjoyed this post. Thanks
Congratulations for your watch taste and thank you for sharing with us. Great post! nt
Dear John: thank you so much for sharing...
Not being myself a PP collector (though definitively I´m an admirer of the brand) and not having much technical knowledge about movements, I enjoyed so much reading the comments of the watchmaker as he dismantled your watch for service, and explained the features of this marvelous movment, and the problems he found in it.
I´m sure he will be able to restore it to its full functioning grandeur and ship it again to you to enjoy.
It is incredible how much care PP dispenses to parts of its movement which will never be seen by any other than the original assembler and in any case, the watchmaker who will service it!
This clearly speaks about the Brand, and that the fame it got through its lifemaking, is so well earned, not only by the beauty of design, and precision in functioning, but for the excelence in finishing. It is often said that quality shows in the small details, and those details shown here, are really fantastic.
I should add, that the only Patek I own in my collection, is a reference 1589 from 1949, which incidentaly, has a similar movement caliber 12-120, which looks very similar to yours, and so it was a delicious experience for me to view and read this post, and learn a bit about its characteristics.
Thank you so much again, and I send you my cordial regards, wishing you´ll keep enjoying your Calatrava for many, many years, in good health.
Best cordial regards, Abel.
I would...
Hi John,
I am pretty sure the dial is in original condition - I would not restore it.
The damage on the case should be an easy fix - go for it.
The Calatrava is an all time classic design, Ref. 96 is a bit small - I have the larger Ref 570 which is the
perfect choice for me...
enjoy your marvel!
erich
I've decided to..
