Number of knots on durability and tension hold ...

Discussion in 'Badminton Stringing Techniques & Tools' started by hoozswup, Jul 31, 2011.

  1. hoozswup

    hoozswup Regular Member

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    Hi! Out of curiosity, is there any correlation between the number of knots and durability? I have seen 1, 2, and 4 knots used on my racket. Legend has it that 1 knot is least durable. ;)

    Secondly if you could comment about its effect on tension hold. Would like to resolve a "fact or fiction" mystery whether the number of knots affects durability or tension hold. Thanks.
     
  2. xZhongCheng

    xZhongCheng Regular Member

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    1 knot? I dont know if thats possible.

    I have used 2 Knot and 4 Knots. IMO, 2 Knots is the best, as it holds tension alot better. 4 Knot is what the yonex regulation is. So if you are worried about warrenty, do 4 Knot. Also if you like to Mix strings, you must use 4 Knot
     
  3. Blitzzards

    Blitzzards Regular Member

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    How is that possible :confused:

    Scientifically speaking, a 2 knots string job is really a piece of very long string stretched through all the main and cross string passes at the strung tension, compared to a 4 knots job which is two short and separate (not joined to each other like the one above) strings at both the main and cross string passes. A very long piece of stretched string will of course lose tension earlier after the string job is complete as there is more mass to stretch compared to two short strings woven together.
     
  4. xZhongCheng

    xZhongCheng Regular Member

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    From personal experience, I found 2 knots to be better. I used 4 knots for a good year. Also with both techniques, I strung the crosses about 2-3 pounds tighter than the mains. I did always find the 2 piece stringing (4 knot) to lose tension alot quicker than the 1 piece stringing (2 knot) I did test this out using the the same string as well. And I did find 2 knot holds tension alot better. Most the people I know, use a 2 knot stringing technique as opposed to 4.
     
  5. Blitzzards

    Blitzzards Regular Member

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    In this case my experience is the opposite of yours. The 2 knot string jobs I have had, even from the same stringer always lose tension before the 4 knot string jobs. Which led me to believe in the scientific fact I just stated.

    Perhaps you have a modified string pattern different from the standard Yonex pattern? Otherwise I would say 2 knot string jobs feel tighter than a 4 knot string job even when at the same tension, initially when fresh from the stringing machine. This is because the long piece of string is resonating or stretching at the same instance during shuttle impact compared to the two shorter pieces of string, where one is longer and can stretch more and give a looser feel. The higher tensioned cross strings would not matter as much as you will always feel more significantly of the longer piece of string which has relatively more mass, which when they stretch will give a more significant "stretching" feel.

    Could it be for your case that your 2 knot string jobs would drop to the tightness associated with your 4 knot string job from initial while the later stays at the same tightness so in a way you feel that the 2 knot string job retains tension relatively longer? How long is your observation period and what string is it that you observed this with, may I ask?
     
  6. pBmMalaysia

    pBmMalaysia Regular Member

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    Can you explain how the one knot is done? I really have no idea ??? Thanks :)
     
  7. pBmMalaysia

    pBmMalaysia Regular Member

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    Yes, most probably because of the loosed last string when the knot was tied:)

    No matter how good the stringer is, the last string after the knot is tied will not be the same as the second last string :D
     
  8. hoozswup

    hoozswup Regular Member

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    Thanks for the reply, glad to see all the responses. Ha~ I thought I have seen 1 knot when I was a teenager, guess the "other" knot must have been hidden/pulled inside the grommet... thus the illusion of 1 knot stringing. :p (sorry!)

    I just found this link from Shuttle House, http://shuttle-house.com/EN/service/string.php (not so well translated, conflicting info). Apparently there's 6 knot stringing and per the site, at one point, it says the more knots reduces stress on the racket frame. Further down the page, it says the reverse. So a bit confused I guess... :confused:, also curious about their "special stringing technique". :rolleyes:

    But judging by xZhongCheng's comment about Yonex warranty and 4 knots, then I would venture to guess that 4 knots put less stress on the frame then 2 knots. Now I hardly see 4 knots stringing.

    Considering getting an affordable stringing machine and start experimenting. Since I am in SoCal, Eagnas makes sense since I can drop by to pick it up (no worries about missing pieces). Hmm... so much to learn, should be fun!
     
  9. Blitzzards

    Blitzzards Regular Member

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    I read the link; and you are correct in stating that it is confusing. The first line actually mistranslated the number of "support points" on a stringing machine to "knots" :D

    The more the number of support points around the frame during stringing, the better the machine will be able to hold the racquet frame in shape during the stringing process. You will notice that when stringing using a 2 point hold down (the simplest and cheapest of machines available), the frame will distort and become more oval or egg-like when you string the main strings and before you string the cross strings. Sometimes when stringing very high tensions and with a little mistake during the tensioning, the frame can snap.

    While on a 6 point support machine, the frame is held very safely by the four additional frame side support arms (plus the two north south support points at the top of the frame and at the neck which gives a total of six) so chances of the frame breaking are extremely very low provided that you install the racquet frame properly (no matter how much a stringer tells you that even with these extra support points, that it is still dangerous to string high tensions, it is really the stringer who is inexperienced with the machine and does not know the science and technique behind using it).

    Eagnas has a very good range of choices for stringing machines so you would not go wrong easily provided that you ask them for the best suggestions, a lot. Good luck!
     
  10. Blitzzards

    Blitzzards Regular Member

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    By the way, the reason why a 4 knot pattern puts less stress on a frame is simple because the main strings are not connected to the cross strings such as a 2 knot pattern is. And because the point where the string transitions from main to cross is at the very side (4 to 5 o'clock or 7 to 8 o'clock) of the racquet frame, when the racquet frame warps slightly during a mishit the string could "pull through" and increase the warping exponentially and cause the frame to distort and snap. While on a 4 knot pattern since the main and cross strings are separate on their own tie off knots (two each) there is no chance for a string "pull through" thus making the chances of the frame distorting unrecoverably much less.
     
  11. visor

    visor Regular Member

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    it all depends on your stringer's skills in pulling the last main and crosses, and also on their skill in tying those knots

    if not so good, then the more knots to tie will mean more points for tension loss, hence for them, 2 knots would be better

    for the skilled stringer, they know to add extra pound or two to the last main and cross to compensate, and their knot tying skills are better, so for them, 2 or 4 knots make no difference...:D
     
  12. xZhongCheng

    xZhongCheng Regular Member

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    Hmm I guess its a trade off: Lose a little bit more tension, or have a higher chance of the frame snapping :(
     
  13. Blitzzards

    Blitzzards Regular Member

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    Actually, referencing visor's comment on knot tie-off technique, I recommend you the [Richard] Parnell Knot. Just add about 2-3lbs more on your last main or cross string directly before you tie-off with this Parnell knot and pull it tightly on the other end with pliers and it should keep your string bed as tight as possible, even with a 4 knot pattern :)
     
  14. xZhongCheng

    xZhongCheng Regular Member

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    I did add the extra 2-3 pounds, but still, it still lost tension. I might try 4 knot again. considering what I have seen here. I do still have room to experiment, since I do got 3 rackets on my own :)
     
  15. hoozswup

    hoozswup Regular Member

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    Blizzard, ha-ha... thanks! Everything makes sense now after your explanation. :D

    When I get my machine, I will lean towards stringing 4 knots on my own racket mainly because it does not stress the frame as much. And to compensate, I will add the extra 2-3 lbs on the last string before tying up using the recommended Parnell Knot.

    Thanks all, learned something very useful!
     
  16. kwun

    kwun Administrator

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    this is my take on it.

    once the knot is tied, the knot itself won't lose any tension over time. at least not from slipping. if the knot ever slip, it will be very apparent, as we will eventually see the loose end of the knot move into the knot and eventually undo the knot itself. and personally with the decades of badminton rackets i have rarely seen a knot slip that way.

    so any tension loss will either be the stretching of the string itself after the knot was tied, or tension loss during the tying process.

    to address it, there are two ways to do it.

    1. pull the string 2-3 lbs tighter to compensate for the loss.
    2. tie the knot well to avoid tension loss.

    the former once is simple to see. 2-3 is a guessimate but seems to be at the right ball park.

    the latter one is harder. how to properly tie a knot? as it turns out there is a knot that allows for tightening of the string while the knot is being tied, and then holds onto the tension during the process. Alan Kakinami of Synergy Badminton demonstrated this in the stringfest video (around 1:50)

    [video=youtube;gkyPbOfzwrU]http://www.youtube.com/watch?v=gkyPbOfzwrU[/video]

    i am using this knot regularly now. it is compact and easy to tie and provides minimal tension loss.
     
  17. Mark A

    Mark A Regular Member

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    There's probably a way to guess how much tension is lost on a knot, or at least put an upper limit on it.

    Once you've clamped the last main you can measure the length of string from the outer edge of the clamp to the knot, and assume it is at zero tension; it'll be about an inch. The ratio between this inch and the last main PLUS this inch will be the minimum percentage overpull for the knot. Coincidentally, it looks to be about 10%.

    Since the last main/knot loop isn't at zero tension - assuming you actually pull your knot - you can get away with less than this.
     

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