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Can't find the screwdriver HA!

  1. Nov 21, 2011 #1

    gulfcoastfella

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    This may seem like a lowbrow request, but I'm looking for a specific screwdriver to give my Dad for Christmas. I saw it advertised "Only on TV" once, and haven't seen it since. I was wondering if someone has seen the same thing and knows what it's called or where I could find one.

    It's a ratcheting screwdriver. Set the ratchet one way and no matter which direction you turn the handle, the shaft rotates clockwise. Set the ratchet the other way and no matter which direction you turn the handle, the shaft rotates counter-clockwise.

    Thanks in advance!
     
  2. jcsd
  3. Nov 21, 2011 #2
    Last edited by a moderator: May 5, 2017
  4. Nov 21, 2011 #3
    You wrote,

    "Set the ratchet one way and no matter which direction you turn the handle, the shaft rotates clockwise."

    From a physics standpoint, is that possible. If I apply a clockwise torque how could the screw move counterclockwise? You would need two hands for such a device to work?

    For gift ideas see,

    https://www.google.com/search?q=ratcheting+screwdriver&tbm=shop&hl=en&aq=2&oq=ratcheting+
     
  5. Nov 21, 2011 #4

    S_Happens

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    ^Obviously did not read the original post. Notice it's not simply a ratcheting screwdriver. (That was meant for gsal)

    It's a Kobalt Double-Drive. I'll edit a link in when I find it.

    Edit- Here's a description. http://toolguyd.com/2011/09/kobalt-double-drive-screwdriver-set-preview/" [Broken]

    Looks like Lowe's online is sold out.
     
    Last edited by a moderator: May 5, 2017
  6. Nov 21, 2011 #5

    gulfcoastfella

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    No, those aren't the right kind of screwdriver, I guess I wasn't clear.

    Assume the ratchet is in position A. Then turning the handle CW will turn the shaft CW, and turning the handle CCW will also turn the shaft CW.

    Flip the ratchet switch to B and the shaft will always rotate CCW, whether you turn the handle CW or CCW.
     
  7. Nov 21, 2011 #6
    So such a device would require two hands to operate?
     
  8. Nov 21, 2011 #7

    gulfcoastfella

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    The handle is connected to the shaft by a set of gears.
     
  9. Nov 21, 2011 #8

    S_Happens

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    Your comment still stands incorrect. See my edited post for the link to the tool he's asking for. (Heh, we're in some kind of editing warp, where posts soon lose their context)

    Link Again- Just in case http://toolguyd.com/2011/09/kobalt-double-drive-screwdriver-set-preview/" [Broken]
     
    Last edited by a moderator: May 5, 2017
  10. Nov 21, 2011 #9

    gulfcoastfella

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    That's exactly what I was describing. Thanks for finding it.
     
    Last edited by a moderator: May 5, 2017
  11. Nov 21, 2011 #10
    From the link it looks like you use two hands and must for it to work?

    Edit, reading the link further, yes.
     
  12. Nov 21, 2011 #11

    S_Happens

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    Yes, it requires two hands. You hold the collar with one and twist with the other.
     
  13. Nov 21, 2011 #12

    DaveC426913

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    You have both options.

    "To engage the Double-Drive mechanism, you hold onto the screwdriver’s blue sleeve with one hand, and turn the handle with the other. If for some reason you cannot hold onto the blue sleeve with your other hand, the screwdriver will still operate in the same manner as a ratcheting screwdriver."
     
  14. Nov 21, 2011 #13

    gulfcoastfella

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    Thanks for finding it. I just bought one on eBay since Lowe's was sold out; and if Kobalt holds the patent, that would explain why I saw the commercial for the other one just once. They must have pulled it from the air.
     
    Last edited by a moderator: May 5, 2017
  15. Nov 21, 2011 #14

    S_Happens

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    I suppose if you REALLY wanted you could rig up some vice grips or a clamp to hold the collar if you wanted to only use one hand. That's just silly though. :P
     
  16. Nov 21, 2011 #15

    S_Happens

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    I can't find the short commercial, but the one I've on TV is specifically this Kobalt one. There is a longer one with prices and all on the Kobalt site.
     
  17. Nov 25, 2011 #16

    HNB

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    Do people really need to think about which way to unscrew and which way to screw?
    Do people prefer using 2 hands than one so that they don't have to think about which way is to screw and which way to unscrew??
    Did people got paid to think about such an idea and engineer that device???
    Do people relly buy such thing for anything else than birthday present (or father's day)????

    Einstein said 2 things have no limits... :biggrin:
     
    Last edited: Nov 25, 2011
  18. Nov 25, 2011 #17

    DaveC426913

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    I think you are making assumptions about how the device is meant to make driving screws easier.
    For one, it's not about 'not having to think which way to screw'. One of the things it does do is make more efficient use of the motion you already have to do anyway. It does twice as much work for the same motion.

    No he didn't. The internet is not your friend.
     
  19. Nov 25, 2011 #18

    HNB

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    http://quoteinvestigator.com/2010/05/04/universe-einstein/

    He is credited to have said it. But what is said does not engage, only what's written does (who said that?).

    ANYWAY...

    "more efficient use of the motion" ???

    Is a simple turning rotational motion of one hand less efficient than a (less simple) turning rotational motion of one hand, while holding the other part of the screwdriver with my second hand? I'd say no
     
  20. Nov 26, 2011 #19
    Your forgetting the limited range of torsion of the wrist, which otherwise has to do an (time-) wasting backstroke -- likely up to 4 of them per rotation of the screw.

    Don't get me wrong, I just saw the ad for the first time Friday morning, and while I thought it was nifty, I felt the rationale was weak: it is only said to fully set screws faster than rachet or manual drivers--which I can imagine, but how many people really need *that* and don't use (swiveling) electric screwdrivers? Even factories usually opt for a powered drive.

    I might pick one up if I see it in the bargain bin, but I wouldn't count on *needing* it often.

    This, paradoxically, may make it a good gift. The mechanically minded often appreciate mechanical niftiness, but also see the impracticality. Some say the best gift is something you'd enjoy but would never buy for yourself. A young man's dad may have more money, but this tool acknowledges dad's interests, and it is easily returned (Kobalt is the store brand of one of the big US hardware chains) to get something Dad wants more, when he gets bored of it.
     
  21. Dec 3, 2011 #20
    After seeing the animation part (around (:28 seconds) of the video of the screwdriver in action, I am still left with the physics question as to how this gearing is accomplished. See video below:



    Is this a new method of gearing unknown before now or has their already been this type of gearing in use in a different manner. It almost appears to be magic, even when I slow down the animation part. Thanks for any insite!
     
    Last edited by a moderator: Sep 25, 2014
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