String Tension versus Sweet Spot

Discussion in 'Badminton String' started by TeddyC, Jan 23, 2015.

  1. TeddyC

    TeddyC Regular Member

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    Just a consensus bout sweet spot of the string bed. Most of us have experienced it while trying to discover our individual preference for string tension. That is, sweet spot is inversely related to string tension: the higher the string tension, the smaller the sweet spot is.

    My inquiry is how much will a tension change of one pound affect the sweet spot area (in terms of inward or outward chg in mm)?

    For ur consideration, am using ZM65 (0.65mm) @28/26 lbs.
     
  2. PinkDawg

    PinkDawg Regular Member

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    o_o I'm not sure if anyone can answer this question, mostly because no one really calculates sweet spot. By feel, the sweet spot doesn't really change that much with just one pound, but it's noticeable.
     
  3. TeddyC

    TeddyC Regular Member

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    Am not asking for a badminton professor, much less anyone, to give any calculation
    ...LOL
    { ^.^}

    How much noticeable is the chg? Between 1 to 5 mm, whats ur estimation?
     
  4. paulstewart64

    paulstewart64 Regular Member

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    I agree this is a difficult questions to answer.

    May I suggest a 5% reduction. It's not a lot and unlikely most players will notice the reduction. However, if you changed tension from 20lbs to 25lbs I'm sure there is sufficient margin now for you to detect the change.

    Paul
    www.badminton-coach.co.uk
     
  5. DuckFeet

    DuckFeet Regular Member

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    I suppose technically you could calculate the sheer stress(?) You can exert on the string and compare to what length of string you can bend at a given tension. Outer strings are shorter so effectively a higher tension. It's way above my scientific abilities. I think string at half the length feels like twice the tension effectively.

    As a rough guide, 22lb feels about 18 crosses wide or a handspan with fingers spread, 25lb maybe size of a clenched fist. Not sure how linear the relationship is. Mark A's old 32lb job felt like a 50p piece!
     
  6. ucantseeme

    ucantseeme Regular Member

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    I think it's really difficult to determine the size of sweetspots, if different stringer, strung different rackets on different machines with different techniques. Aside from the size of the sweetspot it's important if you can hit it consistant. I have met a stringer who strung at sudirman cup, so he should be a good to decent stringer. He did proportional stringing for the mains and cross on my rackets. I must say that he did a decent job but i went higher with my tension. He did 32x32 in the middle and faded out to the sides/bottom. He also started at the top with a few lbs less. As I start stringing I strung all the same and at 2lbs on the cross. My own jobs had a noticeable smaller sweet spot. To make it short: It impossible to compare unless you have various tensions on same rackets with no change like stringer, machine , technique or main/cross ration.
     
  7. TeddyC

    TeddyC Regular Member

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    Tks folks for ur response...

    Let me ponder on it a bit more...
     
  8. TeddyC

    TeddyC Regular Member

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    Difficult indeed. Otherwise, I wouldnt have asked it here...
    { *.^}
    Not to worry, am not asking for a mathematical formula or sorts...

    5% chg seems reasonable, though am thinking of somewhere in the 3% region. Then thats just pure conjecture on my part...
     
  9. TeddyC

    TeddyC Regular Member

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    Touch n Feel method... classic! Tried this on a 20 lbs stringbed. Definitely not easy to feel where the oval sweet spot starts. Felt pretty much the same all over the bed. Cant imagine for a 25 lbs stringbed...

    Am surviving @27lbs, so a fist-size sweet spot is gd enough. Mark must have been a sharpshooter with that tension!
     
  10. ucantseeme

    ucantseeme Regular Member

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    It could be that it's not so easy. To create a rule of thumb like x% you should need some measurements. Maybe it could be a good start to develop a method measure the sweetspot. I don't have any clue about how to do that. I find it interesting talk about this, but it's not really practical. If you hit off center too much, your tension is too high. For me it's enough to know that I can't hit the sweet spot consistent, regardless how large or small it is.:p
     
  11. TeddyC

    TeddyC Regular Member

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    It'll b a hassle, I concur, but feasible... might know of someone here who just might b swayed to do it...
    { ^.^}



    LOL... sounds just like me... half of my frame shots actually n unexpectedly went in, gaining some pts to my embarrasment... ( Y.Y)
    In my case, it's the timing of the swing rather than tension being too high, I suppose...
     
  12. visor

    visor Regular Member

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    Just a question, does anyone actually aim to hit on the actual sweetspot (lower gray area) or a few cm higher (blue area) ?

    Because the stringbed sweetspot is below the centre of the racket face, and this area even though it may have power, but it has much less speed than a few cm further up.

    [​IMG]
     
    #12 visor, Jan 25, 2015
    Last edited: Jan 25, 2015
  13. FeatherBlaster

    FeatherBlaster Regular Member

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    I think the most difficult thing here, is that the sweet spot is not "on/off" like in the diagram. It's a blurry border where you gradually go from good to worse over a few cms. And a hard stringbed may also impact the area just outside the softer stringbed sweetspot to become even worse.
    So the area you'd like to hit, gets a little bit smaller, but the area you don't want to hit, gets worse.
    However, the sweetspot for the hard string bed, might even improve for you, and get better, if you are a hardhitter. All small changes you need to quantify and compare, not just the "size" of the spot to worry about.

    I guess that's why "try" and "feel" is what you have to do. Not calculate.
     
  14. FeatherBlaster

    FeatherBlaster Regular Member

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    Visor, I think I'm aiming at hitting around the border between blue and grey in your diagram.
    I'm playing again now, in the 40+ age group, after a very long break (having played at a very high level before the break).

    I found myself mishitting many hard smashes too high in the racket, because of my footwork (and substantial weight gain) no longer elevating me as high as I used to :-(

    Took a couple of months to adjust. Now I hit them OK, but lower and thus not as steep. (I'm 6'2-6'3 so I can get the bird downwards anyway, even without much of a jump).
     
  15. FeatherBlaster

    FeatherBlaster Regular Member

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    I guess it'd be usefull to color up the strings a bit now and then, to see where you actually hit them. Black and red for high/low spot, or something like that...
     
  16. wongmb

    wongmb Regular Member

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    Look at where ur string frays first will also give u a hint ?
     
  17. TeddyC

    TeddyC Regular Member

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    Thats the norm but most of us cut string before it frays due to tension loss...
     
  18. TeddyC

    TeddyC Regular Member

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    Understood what u tried to imply. Found my TK-9ooo optimal sweet spot to b somewhere in the blue region (this was mentioned in the 'TK-9ooo' thread).

    When that spot is hit, there is a solid reverberating effect on the headframe n the birdie will go in fast n steep. Plenty of power to b exploited up there.

    In comparison, hitting the grey region will just make the birdie go further n less steep. Much easier for the opponents to clear.
     
  19. |_Footwork_|

    |_Footwork_| Regular Member

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    What the heck should this be good for?
    You never look at where you hit the shuttle!
    You do your shots and feel whether you hit it right. If it feels bad, you change your swing/timing/whatever.

    I have never in my life thought about the sweetspot of a racket. It's more implicit, that you go for a good feeling and thereby automatically adjust in a way you hit the sweetspot...
     
  20. |_Footwork_|

    |_Footwork_| Regular Member

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    Do you really think so?
    I have never cut a string. I always play them until they break...
     

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