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DIY: How to shorten a JB Champion Mesh Strap – (NASA strap)

  1. Stuie Feb 14, 2016

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    Hi Everyone,

    Not many posts to my name but I think I have some interesting information to share with the forum.

    First of all I have to thank TLIGuy and imaginager (omega forums) for without their posts showing an example of how links connect together, I wouldn’t have had the confidence to alter my JB champion
    https://omegaforums.net/threads/jb-champion-salvaged.30650/#post-350197

    This post from TLIGuy helps explain how to adjust the bracelet properly
    https://omegaforums.net/threads/jb-champion-salvaged.30650/#post-369539

    So what is so special about a JB Champion mesh bracelet and why is it now fetching $700+ on eBay ?

    Well as most of you are aware the JB Champion mesh bracelet was worn by the NASA Crews of the Gemini and Apollo missions.

    The MOON ONLY WATCH book has a very good chapter to help identify the various types that were used.

    http://www.moonwatchonly.com/omega-...ws/komfit-forstner-and-jb-champion-bracelets/


    BRACELET DETAILS - MAX / MIN WRIST SIZE, DIMENSIONS ETC.

    Compared to most straps/bracelet the JB mesh is rather long.
    With the size adjuster at its smallest setting it requires a wrist size of 6.5” or bigger to give a comfortable fit.
    Smaller than 6.5” and the bracelet will probably be too loose to remain comfortable for most people.

    The one I purchase stated “Extra Long” on the box but all the forum members I have asked seem to agree that these mesh bracelets only came in one size.
    [​IMG]

    Here are the measurements from mine.
    Spring bar to spring bar – 5.5in / 140mm (Adjuster on smallest setting) - See post above for TLIGuy’s explanation on how to adjust properly

    [​IMG]


    Spring bar to spring bar – 9.75in / 245mm (Adjuster on biggest setting)
    [​IMG]

    Attaching a Speedmaster adds about 45/48mm
    [​IMG]

    With the bracelet on the smallest setting you can see that 6.5in is smallest wrist size giving a comfortable snug fit.
    [​IMG]
    [​IMG]

    So if you have small wrists are you out of luck ?

    Well it can be shortened – it’s no too difficult but there is a small chance you could break something ! ::shy::

    HOW TO SHORTEN - JB CHAMPION Mesh Style Bracelet

    ! DISCLAIMER !
    Below I have described how I was able to shorten my bracelet – It’s pretty straight forwards and it’s a tough bracelet, but if you chose to perform these actions on a JB Champion mesh you do so at your own risk. :) ::screwloose::

    (My wrist is 7.25inch so the standard length fits my wrist fine already. My reason for shortening it was so I could put a Timely Wrist Calendar on the bracelet.)
    [​IMG]

    First you have to remove the spring bar ends – (This is the most delicate bit – take you time, move slowly) :thumbsup:

    Slide a blade under the small tabs that wrap around and hold the ends together and gentle prise it up and way a tiny bit

    Slide the blade down and between the edges to gently lever the tab away from the main body.
    [​IMG]

    Once you have done this it should fall away from the mesh leaving you with two teethed parts.
    (Top piece has 5 teeth and the bottom on my horned end version contains the spring for the 16mm-19mm springbar ends – this has 6 teeth)

    [​IMG]

    Next decide how much you need to remove in order for the bracelet to fit how you want it.
    (I needed to remove 22mm so I marked 11mm on each mesh strap to keep the bracelet equal)

    [​IMG]

    [​IMG]

    Once you have marked the row that needs to be removed start to pry each link with a jewelers small screw driver.

    After doing one side turn it over and pry the other matching links.
    Then you can pry out the two edge links
    [​IMG]

    [​IMG]

    (Note: In first picture I practiced removing some links on the first mesh strap before starting on the actual row I marked to remove. 2nd picture is the second strap) ;)

    Having removed all the links you think you need to size it properly for your wrist, its best to check that it is in actual fact the correct length !! ::shy:: ::rant:

    Before putting the springbar ends back properly I attached the bottom toothed spring bar pieces on to a Speedmaster case with spring bars, hooked the mesh on the 6 open teeth and then sellotaped the bracelet to the spring bar piece. Then carefully tried the bracelet on to make sure the new position of the adjuster was where I expected it to be leaving enough room to fit a Timley Wrist Calendar

    REASSEMBLE THE BRACELET

    If you have taken the bracelet fully apart like I did then there are things to watch out for before you start to attached the springbar ends.

    Make sure you have both mesh straps back as they were before you started – they should slide past each other smoothly when wrapped around your wrist.

    Attached the clasp to the flip lock adjuster and check to see that you have inserted the mesh strap pieces together correctly. If not unclip, pull apart the mesh straps, turn one over and reinsert together.

    When wrapped around you wrist the outside mesh should have 5 holes/slots at the very end where the top springbar end will attached again.

    The underside should have 6 holes/slots.

    [​IMG]

    So depending upon how many links you removed you may have to remove just one more to have 5 holes/slots on the top and 6 on the bottom.

    If this is not correct the springbar pieces will be offset to the bracelet when you try to reattach everything.

    Once you have both springbar ends correctly aligned with the teeth biting in to the mesh strap, lay it down so you can compress and secure the two little tabs to hold the whole springbar end assemble again.

    To prevent marking anything place a strong plastic bag etc over the top.

    Next use pliers to compress the top springbar end (now underneath).

    Once compressed back to its original position, use the nose of the pliers to fold the tabs inwards so they prevent the two toothed springbar end pieces from coming apart.
    [​IMG]

    That’s all there is to it…::popcorn::

    [​IMG]
    [​IMG]
     
    Edited Sep 25, 2017
    Rman, marco, Dre and 15 others like this.
  2. TLIGuy Feb 15, 2016

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    Well done and looks great. Glad it worked out for you.
     
    Stuie likes this.
  3. gemini4 Hoarder Of Speed et alia Feb 15, 2016

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    Good to know if my meaty wrist shrinks. Good job.
     
    Stuie likes this.
  4. Fredrik (Swe) Feb 15, 2016

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    Awesome guide, thanks for taking your time!
     
  5. JimInOz Melbourne Australia Feb 15, 2016

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    Great post. :thumbsup:

    My only comment would be to replace the pliers for crimping the tabs with a pair of multi grip pliers set to the correct width.

    1702010.jpg

    That way the force to close the tabs can be applied almost parallel to the faces instead of at an angle.
     
    marco, blubarb, JohnSteed and 2 others like this.
  6. fibonacci086 Feb 15, 2016

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    Great Post ! Very instructive, thank you.
     
  7. dennisthemenace Hey, he asked for it! Feb 15, 2016

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    Nice watch by the way.
     
  8. Stuie Feb 15, 2016

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    Thanks dennisthemenace
    I bought my first speedy two years ago - 3572.50 display back.
    That started me down the quest for a vintage speedy the aim being to get a similar model to the reference worn on the moon.
    Over the past two years I had been looking on and off for a 105.012-66 CB or HF serial in the 24m region
    Two weeks ago I was offered a "barn find" 105.012-63 with no "T" flanking "SWISS MADE" and in the serial range 20520xxx

    After referencing the MOONWATCH ONLY i discovered

    105.012-63: -
    First of the Speedmaster Professional with Asymmetrical case - crown/pusher guard
    Dial has no "T"s - produced before Swiss interior ministry ruling in Oct 1964 for "T SWISS MADE" marking Tritium
    Case back has double bevel
    Serial sits between 20.520.xxx > 20.521.xxx so less than 2000 made.

    Hmm well for me that ticks all my "Grail" boxes and more :)

    It needs the movement serviced as the chrono jumps when resetting and a replacement "Flat Feet" Omega stock crown.
    So in the not to distant future it will be taken to STS for a movement service, have the crown fitted and case ultrasonic cleaned - no polishing :thumbsup:

    I will give it a proper review on here when it gets back.

    "Barn Find - condition"
    4.jpg IMG_8657.JPG
     
    Edited Feb 15, 2016
    JohnSteed, Pahawi and LawBrk like this.
  9. lwong Feb 15, 2016

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    As someone with 6.3 inch wrists, who already owns a JB champion mesh and a set of Timely calendars - I gotta say, this is such. a. great. post.

    Thank you!
     
  10. Stuie Feb 15, 2016

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    Glad I could help Iwong.
    Take your time be careful with the tabs - only bend out just enough to get the springbar part in to two pieces.
    Once you are beyond that don't hold back on the links - they a tough little buggers to pry out.
    As I said practice prying out links further up from your final set of links to be removed ;)
     
  11. JohnSteed Feb 15, 2016

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    Thanks for this. Stickies for future reference

    Great posts and watch, GWS
     
  12. Interstellar Feb 15, 2016

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    Hmmm... I wonder if this is also applicable to the Omega Chronostop Mesh Bracelet? Hmm...

    Thanks for this though.
     
  13. blubarb Feb 23, 2016

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    Great posting. Thanks.