ping tail and quality of stringing.

Discussion in 'Badminton Stringing Techniques & Tools' started by kwun, Apr 21, 2012.

  1. kwun

    kwun Administrator

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    here is something i always wondered.

    when we are done stringing a racket, we sometimes hit the stringbed to hear the natural pitch resonating in the strings. we know pretty well that the frequency tells us something about the stringbed stiffness. that's all and good.

    but how about the decay?

    by that, i mean how long the 'ding' lasts. does it do 'ding' and then gone, or does it go 'dinnnnnng' and last longer?

    i sometimes wonder if the longer one means that the strings are less damped, whether the damping is due to something inherent in the stringing process, be it inconsistent tension, or mismatch main/cross tension, or tying the knot wrong or the wrong stringing pattern. any of those things can cause damping or some interference and stops the string from oscillating naturally.

    thoughts?
     
  2. Mark A

    Mark A Regular Member

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    Hmm. My first instinct is that nothing done during stringing (except prestretch and knots - maybe) can possibly affect the damping; it should depend only on

    String thickness
    String tension(s)
    Grommets
    Frame

    There doesn't seem to be any scope for other variables - the string makes the sound, and the frame swallows it:).
     
  3. kwun

    kwun Administrator

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    well, we have to keep some thing constant, like the string type, grommet and frame.

    but what about tension? eg. if i pull each segment with random tensions, then they would not naturally oscillate at the same frequency, and then when we put them together in a mesh, then they would all want to oscillate at their own frequency and thus the whole mesh interfere with itself. and i think the result will be a lot of damping introduce and the whole string bed will feel very dead.

    that's also kinda the theory behind proportional stringing. we want all the strings to oscillate at similar frequency so they will 'complement' each other.
     
  4. kwun

    kwun Administrator

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    when i strike the string bed to get the ping, it appear it depends on where i hit. if i hit 4 or 5 strings spacing away from the frame, the response is very dull and damped.

    if i hit near the center strings, it give a much crisper 'ding'.

    so is that the way to identify the sweetspot, with the potential of finding out the size of the sweetspot, by striking and listening to the location which creates a ding with a long tail?
     
  5. Mark A

    Mark A Regular Member

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    I think you're pointing to "destructive interference". If so, I agree if we're talking about immediate post-string. Makes the whole "10% rule" debate all the more interesting.

    Again, I agree: strings away from the centre are closer to the frame, so the frame will kill everything off before it has a chance to propagate across the bed. Sweetspot = area with longest "ping persistence"? Well, that's the way I've always tested them:).
     
  6. yan.v

    yan.v Regular Member

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    There's a stringing technique in Tennis that constitutes in just that (and probably more). They don't talk about oscillation though, but the "pulling each segment with random tensions" and proportional stringing made me think of this:

    http://www.sergetti.com/
     
  7. kwun

    kwun Administrator

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    this is related but not directly about proportional stringing.I am more interested in know how to early detect whether a string job is good without having to go to the court to try out. and then perhaps from there gain an understanding what type ofvariation in technique will get us there.
     
  8. kwun

    kwun Administrator

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    but first we need to find out how to determine if a string job is good, hopefully without having to go to the gym to hit as that is somewhat subjective and inaccurate.

    if there is some metric say the longer the ping tail the more coherent the strings are, wouldn't that be great?
     
  9. visor

    visor Regular Member

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    ^^ so, your first step would be to see if there is a correlation with ping decay time vs playability , assuming that playability is directly related to a good string job.

    but I would intuitively think that the more coherent and purer the tone, the longer the decay time ... and that is a result of less "destructive interference" from the stringbed as Mark stated.
     
    #9 visor, Apr 21, 2012
    Last edited: Apr 21, 2012
  10. PsyPryss

    PsyPryss New Member

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    Sorry to bring up an old thread, I just started stringing and was wondering why the ping tail sounds like a thud instead of a nice ping with sustain. The racquet isn’t warped and the string bed is firm. Just that it sounds dead. I strung the mains and the crosses at the same tension on a crank machine. The onces from my usual stringer has a nice ring to it. Some help please.
     
  11. rbynck

    rbynck Regular Member

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    Did both of you string the same racket? I find that the Babolat X-Feel Blast as an example does this - what racket is it, which pattern did you use, which string?
     
  12. PsyPryss

    PsyPryss New Member

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    I have a few Cab21s. The ones he strung has a nice ring to it. It's strung at 24lbs on a CP machine. I strung another Cab21 at 23. I used the standard Yonex pattern. The strings are the same on both racquet. BG66UM. I strung a Cab8 steel frame. The shape of the head is ok but still sounds like a thud and doesn't have a ring to it.
     
  13. Kaelhdris

    Kaelhdris Regular Member

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    Maybe it's because you use a crank machine. Depending on how you pull, those can give wildly different results.
    I'm not an expert on crank machines, but i think the way to go is to pull veeery slowly to take as much of the remaining deformation out of the string before the crank locks. Some people also pull every string twice for the same reason.
    Maybe that could help you get better consistency and a livelier stringbed.
     
  14. Rob3rt

    Rob3rt Regular Member

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    Usually the longer the ping the better the feel of the racket/stringjob. But there are rackets that never achieve this long ping = lively feel. Narrow frames like the Jetspeeds, Z-Speed, lot of BS and others for example.
     
  15. PsyPryss

    PsyPryss New Member

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    I’ll experiment. Same racquet same string. Different machine and different stringer. Gonna try varying the main and cross tension. At least no warping and the string bed is firm... Thanks.

    @Kaelhdris I crank slowly just before reaching the set tension.
     
    #15 PsyPryss, May 2, 2018
    Last edited: May 2, 2018
  16. Charlie-SWUK

    Charlie-SWUK Regular Member

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    I'm noticing it's harder to get long pings out of 4+2 frames. My AX77s don't have a long ping either.
     
  17. PsyPryss

    PsyPryss New Member

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    Does it play well?
     
  18. kwun

    kwun Administrator

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    i do noticed that higher tension has shorter pings than lower tensions. so tail length is inversely proportional to tension. what is important is that the tail there instead of a thud.
     
    Yong and PsyPryss like this.
  19. Yong

    Yong Regular Member

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    Nice finding! I was not aware of that and thought of it as the other way around, expecting a long Ping together with an high pitch..
     
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  20. kwun

    kwun Administrator

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    been a LOOONG time Yong! Hope things are going well!!
     

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