Drop Weight Vs. Crank

Discussion in 'Badminton Stringing Techniques & Tools' started by taneepak, Dec 9, 2006.

  1. taneepak

    taneepak Regular Member

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    Stringing machines come in two securing systems, the hold-down and the suspension. The Babolet machine you are talking about is probably a suspension system. There is nothing wrong with this system. If the racquet top inner side is dented or visibly marked or chipped, then it is the stringer's fault-over-stretching the racquet frame when securing it on the machine.
    Besides securing systems there are also tensioning systems, the drop weight, the crank, and the electronic. Contrary to popular belief, constant pull tensioning does not mean quality stringing. What is more important is uniform tensioning and pulling of each string and precise tensioning on every pull. The electronic and the drop weight types have constant pull, the crank is not. However, only the electronic and crank deliver precise tensioning on every pull. Non-constant pull machines like the crank tend to have lower tension than constant pull machines, which vary from minimal if the string clamps are excellent to 10% if the string clamps are floating types or of poor quality.
    Also, there are the side supports, necessary for high tension and minimal distortion stringing.
    Finally, most stringing machines out there are tennis stringing machines, optimized for tennis racquets. As far as I know, only Babolet provides tennis and badminton interchangeable turntables. There are some badminton-only machines, which are slower but better.
     
  2. Pete LSD

    Pete LSD Regular Member

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    Crank deliver precise tensioning on every pull? I highly doubt it.

    Babolat doesn't provide interchangeable turnables. The Babolat badminton kit include load spreaders and plastic pieces for the side supports.

     
  3. Alexccs

    Alexccs Regular Member

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    It does.
    Crack machine DOES deliver pricision tension on every pull. Because it's fast and easy to do with each pull.
    No like drop weight machine hardly deliver precision tension on every pull but it DOES deliver constant pull on every pull if you wait for 15 seconds or more on every pull.
     
  4. Matt

    Matt Regular Member

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    Must be some kind of new strining machine.

    I would agree. Crank machines would deliver essentially a precision pull. The drop is not as reliable because of the nature of the machine.
     
  5. Pete LSD

    Pete LSD Regular Member

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    Not mine drop weight :D.

     
  6. Pete LSD

    Pete LSD Regular Member

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    C (rack) DOES = CDOES ?

     
  7. Matt

    Matt Regular Member

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    Eheheh Pete. You know what I'm referring to.
     
  8. DinkAlot

    DinkAlot dcbadminton
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    Not I doubt it, more like it's impossible. Precise is a very accurate word and cranks are that accurate.
     
  9. DinkAlot

    DinkAlot dcbadminton
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    Wrong, unless a crank machine can have constant pull (and there are none that I'm aware of), it does not deliver a precision pull. The moment the crank locks, you start to lose tension. On my machine, in about 2 seconds, you lose about 0.5lbs. and in about 5 seconds, you lose 1.0 to 1.5lbs.

    I adjust my tension accordingly to account for tension loss.

    So, assuming precision is to the 0.1lbs. The only way you can have a precision pull is:

    1) To be able to clamp off exactly the same way, every time, so your tension loss will be the same

    2) To be able to clamp off in exactly the same time, every time, so your tension loss will be the same

    3) To be able to pull and release the next string in the same way and time so your tension loss will be the same

    4) To be able to align the racket (in degrees) exactly the same every time so your tension loss will be the same

    Assuming all this is done, then you can have a "precision" pull every time. This is extremely hard to do.

    However, if you consider precision to the nearest 1.0lb., then it's possible. :)
     
    #9 DinkAlot, Dec 10, 2006
    Last edited: Dec 10, 2006
  10. Pete LSD

    Pete LSD Regular Member

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    Crank are that in-accurate with that many moving parts, unless you constantly calibrate it :D.

     
  11. CoolDoo6

    CoolDoo6 Regular Member

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    The starting knot going into the grommet shouldnt be a problem. Although this suggests the knot is too small, or too tight. If too small, use more loops. If too tight, start the knot loose and let the tensioning do the tightening, while holding the knot back, rather than tightening the knot by pulling on the cut-end of the string. A knot that is too tight will constrict and bisect the string that the knot is made on when a hard smash contacts the loop string. I have seen this happen enough times to regard it as one of the main reasons for string breakage.

    Continuing on with the tension digression, I think too much significance has been attached to the precision. Stringing is an inherently imprecise process, and it really doen't matter. What matters is the average. Assuming strings are done by the same stringer, on average, imprecisely tensioned 25lb strings are generally more stiff than imprecisely tensioned 23lb strings, even if the actual tensions were 24.8 and 24 respectively. Also when you switch stringer, you will find that the new stringer's tension differ somewhat to your last stringer.

    In my own case, people tell me my strings are tighter compared to their previous stringers, and they adapt by asking for 1 or 2lbs lower on subsequent occasions. It's difficult to say if my tensions are more or less precise than others. As people keep coming to me for more, the answer is irrelevent in practice and needn't actually be answered.

    I am confident of my tensions to the nearest 2lbs on my drop weight machine's scale. The scale itself may or may not be accurate and was manually calibrated using a cheap mechanical fishing hanging/pulling scale. For some unknown reason, my calibrated scale didn't resemble the original factory scale that I subsequently decided to rip off the machine. So you see, the machine itself could be imprecise in the first place.
     
    #11 CoolDoo6, Dec 10, 2006
    Last edited: Dec 10, 2006
  12. cooler

    cooler Regular Member

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    :eek: Your post is longer than mine but we basically said the same things:D :p Yah, petey got it too;)
    http://www.badmintoncentral.com/forums/showthread.php?p=482427#post482427

    said it in 2003 too http://www.badmintoncentral.com/forums/showthread.php?t=12569
     
    #12 cooler, Dec 10, 2006
    Last edited: Dec 10, 2006
  13. taneepak

    taneepak Regular Member

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    Maybe it should read precise tension on every pull instead of tensioning. Yes, the crank and the electronic, but not the drop-weight, machines deliver precise tension on every pull.
     
  14. Pete LSD

    Pete LSD Regular Member

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    :D :D :D Crank is precisely imprecise with a spring(s) and various gears and moving parts subject to wear and tear. Unless you calibrate it for every string job (I know Master Dan does it quite often), the resulting string job varies over time. Electronic machine has a computer and sensor to do instant calibration, within a specific sensitivity (like 0.22 lb).
     
    #14 Pete LSD, Dec 10, 2006
    Last edited: Dec 10, 2006
  15. cooler

    cooler Regular Member

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    ALL THIS PROVE ONE THING I HAD SAID BEFORE (sorry, me too lazy to find that post:D): It's not how expensive of the machine your stringer has, it's how good your stringer can string.
     
  16. DinkAlot

    DinkAlot dcbadminton
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    And on that note, I pick the MicroPower string tensioned at 30lbs. *ting* and say goodbye. :p
     
  17. cooler

    cooler Regular Member

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    hahaha, there is a panda called ting ting already.
    BTW, other panda names taken include:

    xie xie
    bao bao
    lu lu
    and gao gao :D

    hmmm, they all have badminton names:D
     
    #17 cooler, Dec 10, 2006
    Last edited: Dec 10, 2006
  18. taneepak

    taneepak Regular Member

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    A crank machine may be out of calibration by say 2lbs, in which the reading says 30lbs but the out of calibration tension is actually 28lbs. Precise tension on every pull means you get 28lbs on every pull. It doesn't mean you must get 30lbs. Drop-weight machines would have varying tension for each drop.
     
  19. cooler

    cooler Regular Member

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    i understood what u meant but i think u didnt understand our, every crank still wouldn't give u duplicate tension, it fluctuate a bit around a mean.
     
  20. Neil Nicholls

    Neil Nicholls Regular Member

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    Apart from the Laserfibre and similar systems, yes.
    But varying by how much?

    If you get the bar exactly horizontal, you get 100% of your reference tension.
    If you are 5 degrees out, you get 99.62% of your reference tension.
    If you are 10 degrees out, you get 98.48% of your reference tension.

    reference = 24 lb
    5 degrees out -> 23.909 lb
    10 degrees out -> 23.635 lb

    On a 12 inch bar, 5 degrees out is 1 inch above or below at the far end of the bar.
    I doubt if my bar is ever more than 1cm out of horizontal, which is about 1.9 degrees.
    If you are 1.9 degrees out, you get 99.945% of your reference tension.
    1.9 degrees out -> 23.987 lb
     

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