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On My Bench - Seiko 7549-7010 Deconstructed

  1. JimInOz Melbourne Australia Mar 7, 2021

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    I figured I had some more time until Annie got home from the hospital so I finished this one off.

    The movement was cased and the bezel pressed on.
    Then for the part that gives this line its name, the bezel shroud which gave rise to the "tuna can" appellation.
    In this case it's a small can, so a Baby Tuna.

    The shroud is secured by three screws. I applied a tiny drop of Loctite 243 to the leading threads of the screws.

    LoctiteScrew.JPG

    Then all screws were set and tightened.

    ScrewFin.JPG

    With that, this one is done and dusted. I just need to keep an eye on it over the next few days to make sure all is running properly then I'll put in a fresh battery and call it complete.

    CaseFin.JPG
     
    pascs, ConElPueblo, Leeroy and 2 others like this.
  2. LuckyLes Mar 7, 2021

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    Hi Jiminoz,
    How many clicks of the elbow do those screws require?
     
  3. JimInOz Melbourne Australia Mar 7, 2021

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    About 7/16ths of a gentle click Les ;)

    torquejoke.JPG
     
  4. LuckyLes Mar 7, 2021

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    Thanks for that. That is certainly a flash screwdriver. What torque measurements do you use, inch/pounds or finer?
     
  5. JimInOz Melbourne Australia Mar 7, 2021

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    Just pulling your leg with that device Les.
    After working on seeker heads on guided missiles for a few years I got the feel of the right torque for tiny screws (using eye wateringly expensive government torque screwdrivers).

    On this job, it was tighten down until the screw is seated, and then about 1/8th of a turn. The Loctite ensure no back-out or loss of screw.

    Actual torque is largely irrelevant in this application as it's not a compression/tension fastener.
     
  6. LuckyLes Mar 7, 2021

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    Thanks Jiminoz, I think we would probably get on well appreciate the wit.
     
  7. JimInOz Melbourne Australia May 27, 2021

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    An update on this one.

    The owner noticed a strange flickering of the seconds hand every now and again.



    Since I couldn't diagnose by remote control, he sent it back for investigation.

    There was also a speck under the crystal.

    speck.jpg

    I'll blame Australia Post for both of these anomalies :whistling:.

    Anyway, a dismantle and inspection revealed that the seconds hand was slightly loose on the pipe.

    HandFlange.jpg

    When I completed it earlier it may have been stuck in place and subsequent football games by Aus Post freed it.

    It was easy to see the slight movement when the pipe was held stationary in tweezers.



    "Easy fix" I thought, a great gob of glue and Bob's your Uncle. :eek:
    But then I could sense a disturbance in the force, my mentors would not be happy, so I approached one for some guidance.
    I won't mention his name, but it rhymes with:

    Screen Shot 2021-05-28 at 14.38.56.png

    (Dang! I've got Rebus Puzzle fixation).

    Following his suggestion, I set the hand in my staking set on the smallest anvil I had.

    Stake1.JPG

    And used a small dome punch to swage the head of the pipe. A couple of taps with the end of my tweezers and it was done.

    Stake2.JPG

    Now re-assembled, checked and on its way back to the owner, I'm sure he'll be happy to get his baby back.

    Oh, and the speck was removed and consigned to the bin.
     
    WestCoastTime and omegaswisst like this.
  8. topfox59 May 28, 2021

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    That’s a great write up; enjoyed understanding the skills involved with servicing watches
     
    johnborsellino likes this.