Part three - the teardown

Jun 29, 2012,11:55 AM
 




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.

From here on, I use a movement holder to properly secure it.





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.









I remove the cap jewels for cleaning. Perlage on the underside of the balance cock!






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 of obtaining the Geneva Seal is not using wire springs. This is how it’s done! Note that the clutch lever is its own spring at the same time – one component. For me, minimizing component count in that way is watchmaking at its best.

This message has been edited by johnswatch1 on 2012-06-29 12:10:43

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Deep inside a Calatrava - preamble

 
By: johnswatch1 : June 29th, 2012-10:58
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 serv... 

Part one - external appraisal

 
By: johnswatch1 : June 29th, 2012-11:12
Normal 0 false false false EN-US JA X-NONE 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 t...  

Part two - cracking the back

 
By: johnswatch1 : June 29th, 2012-11:31
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...  

Part three - the teardown

 
By: johnswatch1 : June 29th, 2012-11:55
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. From here on, I use a movement holder to properly secure it....  

Part four - the wheel train

 
By: johnswatch1 : June 29th, 2012-12:37
Now on to the wheel train. The 12"'120 movement is beautiful in that it allows you to see the full transmission of power from the barrel (first wheel) through the centre wheel, third wheel, fourth wheel then to the escape wheel and balance. Notice the lit...  

Now some questions...

 
By: johnswatch1 : June 29th, 2012-12:52
First - do you think the dial is original? I'm not one of those collectors that likes to see battle scars so unless the dial is the one it originally shipped with I'll have it refinished. This is a watch that gets worn daily, not a museum piece. With that... 

Great post. Thanks John

 
By: watch-guy.com : July 3rd, 2012-00:33
My opinion FWIW 1. Dial looks original and I would not refinish it 2. I would get the dent on the case fixed All in all a great watch Thanks Julian

I gets my vote for post of the year

 
By: Bruno.M1 : June 30th, 2012-01:12
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

Dear John: thank you so much for sharing...

 
By: Subexplorer : July 3rd, 2012-08:04
... this beautiful post and exchange of information between you and your knowledgeable watchmaker. 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... 

I would...

 
By: mac_omega : July 6th, 2012-07:22
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 pe... 

I've decided to..

 
By: johnswatch1 : July 6th, 2012-13:52
Thanks Erich, The screws are fairly badly scratched so I'm having these poished along with a light polish of the regulator. The dent is going to be fixed and the hands lightly polished to remove the marks acquired over at least 6 previous services. I'm ex... 

Great post ! Thanks !

 
By: Georg : July 10th, 2012-05:19
Really a cool post, very interesting and very good pictures. I am looking very much forward to see the "reverse" process or at least the the finished piece. Best regards Georg