Service – Cortébert Pocket Watch

So, a few months ago Christian very kindly offered to open his blog up to his fans, and i’ve decided to take him up on this offer! My name is Sean and I live in the North West of England. I’m an electrical engineer by trade, but have spent the last 6 months indulging myself in the world of watch repair and renovation, and have begun to reach the point where I repair more watches than I destroy!

Over this period, I have learn’t much of what I know from 2 things. Firstly from my own costly mistakes (usually where the best lessons are learned!), and secondly from the wealth of information available online, and in the second instance, nowhere more than Christians blog. I hope that by adding a few of my own projects, I can pass on some of the things i’ve learned along the way.


The first project i’d like to show everyone is a rather fine pocket watch I serviced for a colleague. It’s a swiss made Cortébert movement in a Dennison gold-filled Half-Hunter case. I’ve dated it vaguely at about 1930’s to 1940’s, and the movement is somewhere between a Cal. 526 through to a Cal. 548, but a highly decorated version. It needs a service and the dial needs cleaning up due to what appears to be a glue mark. Here we go…


You can already see lots off dirt, most of which appears to be dried oil. If you look carefully you can see a missing screw on the bridge. One of the remaining 2 screws on this bridge is actually a ‘blued’ steel screw, whilst all the rest are stainless, so I guess whoever serviced it last lost 2 screws and only had one other that would fit! Seems solid with just the two though, and I don’t have anything that will fit, so it may have to stay that way.


Movement removed from case, this involves popping off the glass & bezel from the front, removing the 2 case screws, and then ensuring the crown is in the pulled out ‘hand set’ position. This is important, otherwise you can snap the stem when removing the movement through the front.


The case is now ready for a clean in the ultrasonic bath, and a gentle polish.


Dial ready for cleaning, the dried glue is visible at the 7. Thankfully it’s an enamel dial, so it’s not too delicate, and I can scrape this off with a piece of peg wood.


Less decoration on the dial side. Lot’s of dried oil though.


I begin disassembly, after letting the main spring down, I remove the click spring etc.


The wheel bridge is off.


The quantity of dried oil is clearly visible, it seems to have migrated everywhere!


Quite strange pallet’s, I’m presuming they are clear because they’re sapphire crystal rather than ruby, but maybe they’re diamond?!


We’re all back together, oiled and cased, and now the hands are set. I check for clearance between the hour and minute hand. I rather enjoy this bit!


Looking nice and clean.


At this point, I test it’s timekeeping and discover she is running about 8 minutes a day fast. Although it’s an old watch, this is still a little too much so I investigate further. The eagle eyed amongst you may spot the issue in the picture. The hairspring is not sitting centrally around the balance shaft, causing 2 coils to touch. This shortens its relative length, and makes it run fast. Firstly I purchase a de-magnetiser and try this, but it doesn’t solve the issue. (Useful tool though!) Next, I take the balance out and see that I have straightened the ‘dog-leg’ in the spring whilst reassembling the balance assembly after oiling. 🙁


At this point I have to make some tools for manipulating the hairspring. I do this by cutting the tops off the heads of 2 needles. This leaves me with 2 tiny forks with which I can GENTLY bend the spring back into shape. I can’t express how stressful a job it is!
After a few lucky slips, it’s as good as I feel i’m going to get it. I put her back together and find she’s about 20-30 seconds fast, laying face up all day, and i’m happy with that!

I begin to fit the glass. and then disaster strikes…..I underestimate how delicate the glass is and crack it 🙁


£30 later and i have a NOS glass fitted and can return the watch to its’s owner.


Which lasts about 30 minutes before I get a text to say his son has put his thumb through it! After some discussion, we decide to opt for an acrylic crystal this time, since they are a fraction of the price and less delicate.


If we don’t like it, we haven’t wasted too much money.


New crystal fitted, she looks fine, and after moving around all day (traveling to and from work a few times!) she seems to have settled at about 1-2 minutes fast a day. I decide that’s good enough for me until I purchase a timegrapher, and will also try and replace the 2 missing stainless screws if I ever come across any in the future.


So, important lessons learned:

1. Beware delicate hairsprings! They are incredibly easy to ruin, and are obviously very important when it comes to decent timekeeping. I hope to not make this mistake again, as manipulating hairsprings takes years off your life!

2. Beware delicate glass! Obviously you have to be careful with all parts of a watch, as there is very little that is not delicate, but Hunter pocket watch glass is the worst i’ve experienced with ‘crystals’. However the modern acrylic replacements, although not in keeping with maintaining originality of the watch, are certainly more durable and you really can’t tell the difference.

Thanks for reading, and I hope to be able to add some more articles to Christians blog in the future.


20 thoughts on “Service – Cortébert Pocket Watch

  1. I have a Philippe Juillard watch. I understand ‘Philippe Juillard’ is founder of Cortebert Watch Co. It is 18 Karat Gold watch, the Dial is also solid gold.
    If anyone knows Philippe Juillard watch, Please contact me and Call me. I need more information of this watch.
    My watch looks like 1970’s made, wrist watch, and hand made watch.
    The dial is also Solid Gold.

  2. I am just servicing a old Longines pocket watch from around 1890. I really have to agree that the older the mainsprings are, the more delicate they are.
    Incredibly thin, blued steel is far more delicate to handle during a service than modern hairsprings.
    You just have to accidentally drop the balance wheel, still holding the balance cock with the hairsping atached to the balance wheel, and the balance spring will go out of it´s shape and can hardly be fixed again.

  3. I bought a Tissot Seastar Visadate in 1964. Can’t recall what it cost, but took 3 months to save enough to buy it. Lovely watch, slim, light, easy to forget you’re wearing it. It survived working in a hotel, then a shipyard, then 4 years in Australia, both in bush and industry, then back in shipyard again (same place, in Sweden). Life was tough back then, took a lot of knocks building ferries and supertankers etc. Hands became loose, never certain it showed correct time, was thinking of buying a new watch when it got broke. The glass melted Been in a box since ’73 (might look for it one day!) After that I broke 2 watches a year, the only ones to survive I rarely used in the shipyards. A Silvana auto, 2 Seiko 5 autos (one needs repair to winder/adjuster, is loose)) Seconda manual wind (winder knob fell off!) Molnija pocket (both bought from Russian merchant seamen who wanted Kronor to buy western goods, Molnija has never worked but looked nice and he sold me cheap vodka too!) Swiss Army (runs ok but now 20 mins a day fast!? Lot of magnetic currents in a shipyard). All the others were so damaged they were thrown out. Shame, perhaps could have been used for spares?
    Tired of batteries, two Seiko rechargables stopped working after 18 months, others burn batteries in less than a year (4 months last time) so am now using a Seiko 5 and the Silvana, both run well, keep good time, Silvana calender doesn’t work, Seiko hour marker came loose, needed removing as it jammed the hands.

    The old mechanical watches are the best. Clean and lube every 5 years they could last a lifetime if damage is avoided.

  4. Proszę o identyfikację i wycenę zegarka Cortebert 14k
    Wróć do listy »

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    ArtNoveau napisał 17.01.2014 o 19:17:
    Proszę o identyfikację i wycenę zegarka Cortebert 14k
    Proszę o ID i ewentualną wycenę zegarka. Jeśli ktoś się z takim spotkał również proszę o komentarz.
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    obraz zaczony przez uytkownika obraz zaczony przez uytkownika
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    ArtNoveau napisał 17.01.2014 o 19:19:

    This site has the watch cover I mentioned with the 12 medals and it was a commeration of the 1933 Worlds fair. My grandmother was from Poland and it seems this writing is Polish. I think this person is selling one. Their’s says 14K. Mark

  5. Thanks Christian, No hallmark, not the Swiss ones I have seen, just a small crown. This watch is in outstanding condition as it was recently given to me by my 91 year old dad and he got it from his mother who had given it to her oldest son who was killed over France in WWII, shot down. Therefore I don’t think it has been out of the box since 1950 or before. As stated the gold colored hands and numerals are striking but I would have liked if the watch had a case with a covering for the crystal/face. Cal.522 means what, anyone? Thanks, mark

  6. I was given a Cortebert pocket watch in very fine condition as it has been stored for 75 years. under the first cover is a very small crown and on the second cover are 12 medals, 5 above and 7 below. one says “THUN 1899” the est need magnification. the face has no cover and never did, all wording and numerals are gold. the workings say cal 522 and it is very clean.on the stem, face side there is something, again very small. the gold hands, numerals are striking. have i given enough to allow you to tell us anything about this watch? could the case be gold or did the storage leave it looking new? thx, mark

    • Hi Mark,

      If the case is gold, it will have a hallmark. If it doesn’t, it’s not gold. You will be best off posting some decent photos on a watch forum site. I am sure you will get a lot of information about the watch that way.

      Best regards,


  7. I was recently given a Cortebert pocket watch. Upon opening the first “door” 12 medals are shown, 5 on top and 7 below Cortebert Watch Company. I need a magnifying glass to read what is on the medals. There appears to be a very small crown on the back of the first cover. on the back of the second cover, which has a machined look it says ‘metal” and the number1566888Here the movement can be seen and it says cal522. The movement is as clean as when new. The watch face has no cover and never had one. The letters/numbers are in gold and the face has gold lines running top to bottom Cortebert is all that is written here. This watch is in fine condition as it was stored for at least 75 years. Can you tell me anything about it as I could not find the same face online even for cal 522’s, thanks, mark

  8. Great first post — I hope you make more.

    I love the canted tip on the minute hand. I found that on the second hand of one of the first watches I’ve worked on, a modern Tissot Visodate. I thought I had wrecked it, until I looked at another one. I’m surprised to see it on an older pocket watch.

    I also like the needle tools — I usually use the tip of a needle (or a clean oiler) plus a #5 tweezer, but this certainly looks worth trying.

    Pretty watch.

    • Mmmm.. I think it’s to do with how shallow the glass has to be on a half hunter pocket watch, if i wasn’t canted like that, it would scratch the crystal. I can tell you, there isn’t much clearance at all!
      I quite like this picture too, my macro lens is getting a lot of work these days 🙂

      The needle ‘forks’ are definitely a step up from a plain needle, but you need to take care the make sure there are no burr’s left that may snag. I buzzed the top of the head off on a grinder, and then dressed the edge with some 1500 grit sand paper. Plus some sort of grip/handle really helps (currently blue masking tape on mine), I started without, and nearly damaged the spring in one slip. Having a decent handle means you can gently roll the ‘fork’s’ between two fingers with decent control.

      On another note, i’ve been trying to find myself a nice vintage Tissot Visodate/SeaStar over the last few weeks and keep missing out, hopefully i’ll get lucky soon!

  9. Nice write up. As to your speculation about the pallet stones… the “ruby” material that is typically used is a synthetic ruby stone that can come in red/pink (most common), a pale blue (very rare), and clear (2nd most common).

    Today’s pallet stones are nearly always red/pink, so any deviance from that is usually found on vintage/antique watches and pocket watches of yesteryear.

    It would seem that using a harder stone (eg. diamond) could contribute to unnecessary wear on the contact surfaces, and hence are not used…. not to mention the cost.

    • Now you mention it, that makes perfect sense. Having diamond pallets would surely just wear the contact surfaces on the escape wheel. It does seem a little strange to me that all the pivot and cap jewels are a very deep ruby red, whilst the pallets are clear.

      After a quick read of wiki it appears that both ruby and sapphire are effectively the same thing (Corundum) with different trace elements giving different colours. You learn something new everyday 🙂

  10. Great post Sean!

    You’ve said you’ve been practicing watch repairing for 6 months. Being able to restore a watch in this amount of time is definitely impressive!

    Would you care to elaborate on your training? Are you self-taught?


    • Lol, thanks! It’s been an intense 6 months 🙂 I’m self-taught, but i’ve been dismantling and tinkering with all sorts of electrical/mechanical things since I was a kid, just can’t help myself 🙂 It helps thats my dad’s an engineer too, it’s made me reasonably practical. I’ve spent a lot of time over the last year or two repairing vintage camera’s and lenses (another obsession!) so getting into the watches has just been about getting a basic understanding of the principles of how a watch works, and then getting used to working under the microscope. Plus, google’s always there to help ;-D

  11. Brilliant write up! Really in the usual spirit of the blog and a joy to read. I keep being told that great-grandfather’s pocketwatch (a different great grandfather this time) is lying about the house somewhere. No doubt that if it ever does appear, it will need servicing.

    I’ve also bought a few scrap movements from eBay, so far, I have only managed to destroy them (usually because of the hairspring), but I’m getting there. I managed to re-assemble one the other day!


    • Cheers Benjamin, that’s very kind of you to say!
      Keep at it, practise makes perfect. The best lessons tend to be the ones we learn when something goes wrong. Fortunately, (or unfortunately!) there’s no shortage of orphaned movements available on eBay to learn with.

  12. I like your hairspring tools – very good idea. I use small tweezers with a double-bend for that job, but I’m tempted to try your needles with a slot next time.
    Pocket watch glasses are a right pain and never last long – I’m all in favour of acrylic crystals for them. Even though it’s not original, it’s not a permanent modification, e.g. you can always go back to glass, and it protects the dial and hands. So from a conservation point of view, I actually advocate acrylic crystals if you want to use the watch. If it just sits in a display case, I’d go for the original glass.
    Great job!

    • Cheers Christian, that’s much appreciated. I have to admit, I didn’t come up with the needle idea myself, I saw that someone suggested it on a forum and gave it a try! It has it’s advantages and disadvantages though, for example, using both forks, you can gently rotate both in opposite directions very gently with reasonable control to make new bends or adjust bends. On the other hand there were moments when I felt I needed to actually grip the spring, in which case fine tweezers would have served better. Also, adding tape (or some sort of handle) to the tip of the needle gives you a much finer ‘rotational control’, and saves you’re fingers 🙂 Thanks again for the opportunity to contribute.

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