• Master
    3 Mar 2012, 7:26 a.m.

    Good Evening Forum Friends,

    So far, all of my small but growing collection contains models with Screw-In crowns.

    My inclination is to want to make sure that the crowns are tightened firm to the case to prevent any intrusion from the outside environment that could cause internal damage.

    My concern is that I may be applying to much force/torque and cause injury to the case or crown. Yet I feel light/delicate tighting should be the way to go but may not provide the protection necessary.

    Who's got some advice or guidelines on this matter that will give me the confidence that everytime I need to screw...it's going to be good !!

    Waiting patiently for your reply,

    Andy

  • Master
    3 Mar 2012, 8 a.m.

    Andy, good point. I have been concerned about how to press in the crown against the spring to ensure that it engages correctly with the thread; can this be a problem and strip the thread?

  • Master
    3 Mar 2012, 2:17 p.m.

    These watches are designed to be screwed in. So, pussh in and screw in until it stops.
    I have never had any problems with screw in crowns.

  • Master
    3 Mar 2012, 3:43 p.m.

    I start pushing the crown carefully, turning it counter-clockwise until I feel a slight click of the crown falling into the thread. Then I turn the crown, carefully again, clockwise until I feel it stop. I then give the crown a last, slender push, and that's it. After all these years all my crowns are still in perfect condition, as I would expect after treating them with respect and care.

    Kind regards,
    Paul

  • Connoisseur
    3 Mar 2012, 4:17 p.m.

    Crowns, if they screw-in, are meant to be screwed. Normal force is fine. At some point, huge torque will strip the threads but this really is highly unusual.

    There's one exception. The reference 5004 could have a problem, and the crown/stem mechanism was redesigned for the new reference 5009. But I've not heard of a problem with the 5004, so it still must involve a lot of force to strip the threads.

  • Graduate
    3 Mar 2012, 4:43 p.m.

    Danke fur da patience!

    If you are truly obsessed by dis matter, you must "scratch da itch"! Micro torque gauges are available for measuring da force werking through da angle. These tools are employed in certain horological assemble (and micro-mechanics in general) where da possibility of "warping" or otherwise deforming da small component ist possible.

    Get out your wallet! After you obtain dis device, we vill determine da pitch, diameter, material, etc. of da threads and derive da appropriate "foot pounds" (Ha ha, stiff always laughs when he says dat because they could have called dem 'stomps', jah?).

    sm iiH!

  • Graduate
    4 Mar 2012, 4:34 p.m.

    Imagine dat! stiff just noticed dat da owner of a 'competing' watch forum (ER) just posted about off all things - da new 'torque driver' from Bergeon dat was unveiled at Basel - da Dynamometric Screwdriver N°6901-TBPR-120. He must read all stiff's posts too.

    sm iiH!