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  1. TDBK Aug 10, 2018

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    I sent my 345.0808 in for service (not to Omega) and the estimate came back including a crown replacement. I believe I've seen discussion about how this is to be accepted, that if a watchmaker is going to stand behind water safety or similar, that they'll have to replace a crown. I'm not sure I'm right: is replacement of an apparently undamaged crown a common requirement? And I'd like to know why?

    I'd rather have safe daily wearability than perfect correctness, so I'm trending towards letting them do the replacement, but asking them to return the replaced crown.

    Thanks!
     
    Edited Aug 10, 2018
  2. Canuck Aug 10, 2018

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    Do watchmakers “stand behind” water resistance? What is the opinion of watchmakers on this MB?
     
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  3. tyrantlizardrex Aug 10, 2018

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    Well I'm not a watchmaker (and don't we know it!), but I understand that rubber seals degrade.

    Even the ones inside crowns. :cautious:

    I'm sure that the folks with legitimate technical knowledge (I believe they call themselves "Watchmakers") can expand upon this. ;)

    Conversations I've had with these educated technical wizards have led me to understand that a lot of crowns are designed to be replaced, rather than dismantled and rebuilt.

    So if you actually want your watch to be water resistant, replacing the crown (with a correct new one) would seem incredibly sensible.

    Given that you have a modern watch, and the replacement crown is the same version as the one fitted, why would you not want it replaced? ::confused2::
     
  4. alam Aug 10, 2018

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    further discussed here
     
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  5. TDBK Aug 10, 2018

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    Ah, I didn't understand that the crown needs to be replaced in order to replace the seal within it. A surprising design choice/constraint, but I can see how it would lead to the policy.

    How old does an Omega watch need to be before service parts won't be identical to original issue? It is 30+ years old. And while collectors definitely see service crowns as in a different category from hands or dials, it's still a part where people apparently care about correctness, if not originality.

    Thanks for the reply!
     
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  6. tyrantlizardrex Aug 10, 2018

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    I could be wrong, but I think the crown design has been the same now since the 1980s (size/teeth/logo).

    If you’re wearing the watch, and you want it to be WR, your safest option is a new crown. Just ask for the old crown back, keep it with the watch, and if you ever sell the watch, pass along the old crown with it.

    It’s cheaper to swap a crown, than pay for a watchmakers time to strip, rebuild and test an old one I’d imagine.

    You also have to think of servicing on scale, providing warranties, and the reliability of a new, known good component vs. the risk of a rebuilt one.
     
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  7. Kmart Aug 10, 2018

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    I've always found this interesting as well. In almost every other mechanical joint you come across, typically you just replace the gasket / o-ring and you're good to go. Seems strange that a watch crown does not have the option to pop the gasket out and put a new one in. It would suck if I had to replace a SCUBA cylinder valve every time one leaked, for instance!
     
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  8. STANDY schizophrenic pizza orderer and watch collector Aug 11, 2018

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    Pretty much the most used touched thing on any watch.

    Think I'm on a 20 - 1 on crown v pushers use on my speedmaster.....
     
  9. gatorcpa ΩF InvestiGator Staff Member Aug 11, 2018

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    That depends on how many watches were originally sold.

    For popular models like Seamaster 300’s, almost all of the case parts are still being made. Up until a few years ago, a company in Australia was buying parts in bulk from Omega and producing “new” vintage watches.

    For others (read - vintage Constellations), the distinctive crowns were discontinued decades ago and Omega recommends a totally different crown as a replacement.
    gatorcpa
     
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  10. tyrantlizardrex Aug 11, 2018

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    Just to add in, the Speedmaster crown/pushers/dials/hands/crystal/bezel/air inside the case "have" to be factory original, or the watch is "worthless" thing is a fairly new phenomenon... for many, many years, people gave somewhere less than zero F$%ks. ;)
     
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  11. ChrisN Aug 11, 2018

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    The seals are not usually renewable - here's a typical construction from a '60s Omega, non screw down crown. Dive watches have a more complex arrangement and there are quite a few different crown designs out there so this is not exhaustive.

    There is a crown outer body (the stem is already fitted), some washers and a seal (the black one in the middle) - some use two O ring seals instead of one long seal.
    crown-_4.jpg
    The crown body takes two washers (in this case) first and then the seal:
    crown-_3.jpg

    Then the remaining washer. The edge of the crown body is squeezed down to hold everything together.
    crown-_2.jpg

    Clearly, these photos are in reverse order as this is a scrap crown. The edge of the crown is crimped/swaged down on top of that last washer so to remove it, you need to lift the edge of the crown body locally to the washer so it can all be disassembled, change the seal(s), put it back together and crimp/swage the edge again. It's the first part that is almost impossible and I pried this up to remove the washer so the crown body is a little damaged there. The best way would be to use a hub puller to try and pull the existing washer up uniformly but, the one from my garage is just a little too big...

    The only practical solution here is to replace the crown if you want the water resistance. For the Speedmaster, they are only about 25GBP to buy so it's not a major expense when compared to the total of the service.

    It would be hard to have a system that allowed for easy seal changes within the space we have. Pushers can, sometimes be re-sealed with new O rings, though. We've only had water resistant crowns for about 100 years and that one used a screw down crown with a seal at the end. These crowns that seal like the one above are a different design and I think the design dates from the fifties.

    It's up to you - I'm clear with my customers that a crown would be required for water resistance in some cases but, if they don't want it, then fair enough - as long as they are aware of that. There are many people out there wearing watches that are not water resistant, especially collectors, but most of them are then careful. In my case, I always try to get water resistance for my watches as I prefer to wear them rather than worry about them.

    In general, yes, if it is water resistant and I've said it is. I recommend checks every 12 months to be sure and you are reliant on people not removing the case back to look at the movement as it would be easy to pinch a case back seal and let the dirt/moisture in, for example.

    Cheers, Chris
     
  12. McKinley Aug 11, 2018

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    Am I the only one who opened this thread expecting to read how someone's dog or toddler had swallowed the crown of their watch? My other thought was that someone had maybe had a new crown sent to them from beyond their home country's boundaries and the crown had been taxed as a "consumable", and he couldn't understand why it was taxed as a food. LOL I guess the way the OP uses the word it means planned obsolescence.
     
  13. BlackTalon This Space for Rent Aug 11, 2018

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    That's funny/ timely. Just before switching over to OF and reading this thread, I was writing about 'consumables' in a car forum (i.e., brake pads, rotors, tires).
     
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  14. Tony C. Ωf Jury member Aug 11, 2018

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    "expendable" may be a clearer wording
     
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  15. Canuck Aug 11, 2018

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    In general, yes, if it is water resistant and I've said it is. I recommend checks every 12 months to be sure and you are reliant on people not removing the case back to look at the movement as it would be easy to pinch a case back seal and let the dirt/moisture in, for example.

    When I water test a watch, I return it with a note that it tested as water resistant (provided it tested water resistant), but I include a note that continued water resistance is not guaranteed. To guarantee water resistance might mean that, should the customer subsequently have an accident with the watch which causes a leak, my guarantee will cover the damage. Since this thread is discussing water resistance of crowns, it should be remembered that the crown is not the only aperture that can admit moisture.
     
  16. Archer Omega Qualified Watchmaker Aug 11, 2018

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    As ChrisN has explained, crown seals deteriorate over time, and in many cases are not easily replaced, so that leaves replacing the crown as really the only practical option. Here's one example of a crown from an SMP and the one on the left is the old crown - you can see the seal has become hard and is permanently deformed (flattened) where the new crown on the right, the seal is still a round cross section, and is fresh:

    [​IMG]

    The seal loses it's sealing ability at this point, but the deterioration doesn't stop there. After a time and in the right conditions, the seals will go through several stages of deterioration in my experience. The first is losing flexibility, then the seal can turn to black goop - almost like tar. If it goes long enough that black goop solidified again and becomes glass like in it's hardness.

    In the black goop stage, the seal material can flow and here is an example where you can see that the case tube of the watch is now covered in that black tar like substance - that is the crown seal...

    [​IMG]

    In extreme cases I've seen the black goop end up down the winding stem and working it's way into the movement. It can be cleaned up, but having that stuff in the movement is not a good thing generally.

    As for standing behind water resistance, a good watchmaker should stand behind their work - if they won't, then find another watchmaker.

    Cheers, Al
     
  17. François Pépin Oct 15, 2018

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    Interesting topic! I would not have thought there were so much to say about crown seals!
     
  18. RedMaple Dec 11, 2020

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    Very informative! Thank you to all who have contributed your professional experience.
     
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  19. SkunkPrince Dec 11, 2020

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    My watchmaker has had some success replacing crown seals in some rare cases. But only when replacing crown tubes too, and it's more dustproof than waterproof.

    We'll see how my two he's working on come out. In both of these cases, the crowns are no longer available except on the secondary market.
     
  20. Dan S Dec 11, 2020

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    Here is a blog post that I greatly enjoy reading, by someone who developed a clever way to remove the washer in order to replace crown seals in old Seiko crowns. It also shows pretty clearly why it is quite hard and labor-intensive to do so. There are a few professional watchmakers who will do this for vintage Seiko dive watches. For some reason, this seems to be something that is more prevalent in the vintage Seiko community, and hasn't really become common elsewhere. I've had this done by a Seiko specialist for two of my vintage Seiko divers, and they successfully passed 10 atm pressure tests. Presumably the professional approach to removing the washer is a bit less "creative" than the one shown in the blog, but I think it's really ingenious.

    https://adventuresinamateurwatchfet...eiko-6105-and-62mas-crown-gasket-replacement/
     
    Edited Dec 11, 2020