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  1. CanberraOmega Rabbitohs and Whisky Supporter Nov 4, 2012

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    Hi all
    I'd like to learn more about what makes a good/bad calibre. I've read about the issue with the cal 500. What is/was the problem? Why is it good/bad? Is it just different metals/alloys? Or are there some good/bad designs? What makes a good/bad design? What improvements/changes in design and alloys have been made over the last few decades?

    I know, lots of questions. Feel free to direct me to an appropriate book/blog etc
    Thanks
    Daniel
     
  2. dsio Ash @ ΩF Staff Member Nov 4, 2012

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    Early 500s aren't too bad apparently, Steve reckons they just need correct maintenance. My dad's 501 piepan's winding system died but it had gone for about 20 years without service, so there's that. Its just that some of the later versions like the 55x and 56x series along with the 75x series seem to be capable of surviving many decades of neglect.

    The chronographs are all solid, 321, 861, 1861, along with ETA 7750 and Lemania 5100 based chronographs are bulletproof. The F. Piguet based 3303 and 3313 are the only exception but they had short production runs and are replaced by the extremely highly regarded Cal 9300.

    Calibre 8500 is probably one of the best modern movements on the market today, impeccable reliability and specifications.

    The early Cal 1000 series seem to have a remarkably bad rep. Desmond described it as "ill-fated", "a disaster" and possessing "birth defects", which is his ever polite way of saying if it were a steer, it'd have been taken up the back paddock and shot.
     
  3. CanberraOmega Rabbitohs and Whisky Supporter Nov 4, 2012

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    So I guess my question is "why"? What makes them bullet proof?
     
  4. dsio Ash @ ΩF Staff Member Nov 4, 2012

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    Design and engineering more than anything, coupled with quality control.
     
  5. ulackfocus Nov 4, 2012

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    There's no easy answer to that. On paper, the caliber 2500 looked like a good idea. In reality, the changes made to the co-axial escapement to stuff it in the caliber 1120 to create the 2500 caused the movement to stop for seemingly no reason. Not all, but enough that there are dozens and dozens of threads about it on various watch forums. The 8500 was built around the correct format for the co-axial escapement and I've seen just two complaints about it in the years it's been in production.

    Many of the older calibers had problems with the automatic winding system. The 40's and 50's saw major changes to the methods used and types of rotating weights used. Full rotors had the majority of their weight on the perimeter. Great for momentum, but hard to balance and stabilize by a central pivot. Frequently these became off balance and wobbled, which made them less efficient - especially if they started scraping other parts. If they were kept lubricated it was okay. Some calibers required more frequent servicing than others. If you see more than 17 jewels in an automatic, it's safe to assume the extra jewels are used in the self-winding system.

    The better automatics had ways to compensate for inevitable wear. Some of Longines' automatics had an adjustment screw near the rotor pivot to simplify balancing. See the caliber 291 and 22S below for example.

    [​IMG]

    [​IMG]


    Longines also tried to make a toothed track at the edge and bearings in the hub to help keep the rotor spinning on plane with the 34x/35x series:

    [​IMG]


    Didn't work so well because of wear to certain steel parts, but with the advent of new materials in watch movements, this (and the LaSalle 2000 ultra-thin automatic) might be worthy of recreation using ceramic for bearings and surfaces that previously wore too fast no matter what condition the lubricant was in. The 291 also had a fantastic reverser system, as did the IWC Pellaton automatics. That's past the basics so we'll save it for a later discussion. Let me leave it at this: less is more when it comes to engineering a way to wind the mainspring despite the way the rotor is spinning.


    Audemars Piguet's rotors had ruby rollers to bear the weight and keep them level - some in the track that the perimeter weight rode on as in the caliber 2120:

    [​IMG]


    ....others in the flat part of the rotor as shown in the following pic of the caliber 2072.

    [​IMG]


    This might be the best solution to the problem of wobble IMO. It's definitely part of the reason many high end collectors think these are two of the finest automatics ever made.



    And that's just about automatics. There's more when it comes to banking pins or lack thereof, balance wheel materials and types, shock protection, etc.
     
    Caesar95, Alpha, pknopp and 1 other person like this.
  6. CanberraOmega Rabbitohs and Whisky Supporter Nov 4, 2012

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    Ahh so much to learn! Really interesting, thanks. I guess I was wondering why the good brands are good and why the Chinese can't do it well - when they can manage almost everything else. And it really is in the margins, the finest points, that make the difference. It certainly never occurred to me there could be so many issues/options/differences in the rotor - which I thought was such a simple concept!
     
  7. dsio Ash @ ΩF Staff Member Nov 4, 2012

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    We still haven't mentioned micro-rotors, bumpers, ball bearings, uni vs bi-directional winding and so-on.
     
  8. pknopp Nov 4, 2012

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    My guess and this is only a guess would be a reluctance to use high quality materials.
     
  9. ulackfocus Nov 4, 2012

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    Or spend the time required to finish the parts properly.
     
  10. Gavin It's the quiet ones you have to 'watch' out for. Nov 4, 2012

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    I have to disagree with that. I think they are up and coming and they are mostly at the infancy stage. Most of them are of low quality and known for counterfeits. But as the industry matures in China, this may change. You may like to see this article on this blog. The blogger is a queer guy but relatively well known in the watch industry.

    http://bernardcheong.com/general/china-and-the-mighty-beijing-watch-factory/
     
  11. pknopp Nov 4, 2012

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    Maybe they will mature but that would have to be seen in future products. I do have some non watch related experience here.
     
  12. Gavin It's the quiet ones you have to 'watch' out for. Nov 4, 2012

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    I think it may be hard to change the perception of their products. But look at the Japanese. They were copying from the Americans and did very well. But since these are luxury products, they face an uphill task.
     
  13. pknopp Nov 4, 2012

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    Later. ;)

    I do have a few thoughts here.
     
  14. CanberraOmega Rabbitohs and Whisky Supporter Nov 5, 2012

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    So does the Goldberger book deal with all of this?