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  1. #35
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    Meanwhile: bought a SW and strung a racket with flying clamps. Yonex pattern bottom up and no problems clamping down last cross string. Great! stringjob was also very good feels like it's been done by electronic machine with pre-stretch function but have to try the racket tonight to confirm. First time took about 45 minutes. If i try some more i could get to 25 minutes i think while tensioning each string about 5-8 seconds. The machine itself is high quality. Everything feels sturdy. Mountingsystem is very secure.

    So far so good. Really impressive

  2. #36
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    Quote Originally Posted by stringtechno View Post
    The graph shows the stress in a racquet for different racquet supports.

    [IMG]http://imageshack.us/a/img189/2774/racquetstress.jpg[/IMG]



    This graph shows:
    - The minimum stress occurs with a 3 point inside system.
    - The stress goes up with an indirect (outside system) when you get closer to 3 and 9 o’clock.
    Therefore it is dangerous to string a badminton racquet with the supports too far away from the head.
    not claiming whether 3 point is better or not. i am still on the fence on it. i just want to gain more understanding of the graph.

    in the 3 point support case, the side support are at 52mm. your graph shows that the stress at the support at 0mm is the highest while the stress decreases to a minimal at the side support at 52mm.

    which makes little sense to me. while i now agree that there should be high stress at 0mm, i think there should be another maxima at 52mm and also there should be another one in between.

    let me shows it by another image to illustrate it:
    Name:  380_display-book-shelfsmall.jpg
Views: 161
Size:  153.7 KB

    in this case we have a similar (but not completely equivalent) scenario, but i think we should be smart enough to realize the similarities. if we keep increasing the weight, we should expect the shelf to have a high stress point right between the two supports.

    that is not apparent on your graph.

    i don't know and cannot claim whether the stress point between the support is higher or the stress point at the support are higher. in either case, there should be a distinct maxima (local or global). but i am not seeing it in the graph you posted..

  3. #37
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    I just want to gain more understanding of the graph.

    in the 3 point support case, the side support are at 52mm. your graph shows that the stress at the support at 0mm is the highest while the stress decreases to a minimal at the side support at 52mm.
    There is a misunderstanding about the graph;
    The computer calculation calculates the maximum stress in the racquet head with the different systems.
    The graph does not show the stress in the different positions!
    It shows the maximum stress in the racquet head for the different positions of the supports.

    IOW
    When you put the support of a 2-point system at 10 mm the maximum stress will be 4 and at 30 mm the stress is 2,2.

    When you put the inside supports further away from each other the stress goes up because the main strings will bend the frame between the supports.

    The calculations are made for "point-supports", so if you make the supports very wide you cover a larger range and make the system right for smaller and bigger frames.

    Or, the other bad things about the indirect (6-p) systems is that the supports are very narrow.

    Btw:
    On forums one always talks about 2-point or 6-point, I think it is better to divide the systems I direct and indirect or inside and outside systems.

    There are direct systems which have much more than 2 points.

  4. #38
    Administrator kwun's Avatar
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    Quote Originally Posted by stringtechno View Post
    There is a misunderstanding about the graph;
    The computer calculation calculates the maximum stress in the racquet head with the different systems.
    The graph does not show the stress in the different positions!
    It shows the maximum stress in the racquet head for the different positions of the supports.

    IOW
    When you put the support of a 2-point system at 10 mm the maximum stress will be 4 and at 30 mm the stress is 2,2.

    When you put the inside supports further away from each other the stress goes up because the main strings will bend the frame between the supports.
    but now that i understand the graphs (and thanks for the explanation), i don't see the 6 point outside support being as bad as you said. afterall, the minima stress value with the support at 175mm (~1.25) isn't that much different than then minima value of the 3 points inside support (~1.5). better, but not that much.

    The calculations are made for "point-supports", so if you make the supports very wide you cover a larger range and make the system right for smaller and bigger frames.

    Or, the other bad things about the indirect (6-p) systems is that the supports are very narrow.
    the size of the support is orthogonal to the support type/point. we can make the inner support smaller or the outer support larger, or vice versa.

  5. #39
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    but now that i understand the graphs (and thanks for the explanation), i don't see the 6 point outside support being as bad as you said. afterall, the minima stress value with the support at 175mm (~1.25) isn't that much different than then minima value of the 3 points inside support (~1.5). better, but not that much.
    This true but that only counts when you position the outside support at the best possible position for a certain racquet. Iow, the position at 175 mm is the best for the oversize tennisracquet but certainly not for a smaller size racquet.
    So totally wrong for a badminton racquet, because you can see that the stress goes up rapidly when you get to close to 3 and 9 o’clock.

    The major problem with the outside supports is that they are not adjustable anymore on the machines nowadays as they were earlier.

    So when a manufacturer would make a realy badminton machine the outside supports should be much closer to 12 o'clock.

    With inside supports the best possible position for every racquet will also be different but less different and you solve that also with the width of the supports.

  6. #40
    Administrator kwun's Avatar
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    Quote Originally Posted by stringtechno View Post
    This true but that only counts when you position the outside support at the best possible position for a certain racquet. Iow, the position at 175 mm is the best for the oversize tennisracquet but certainly not for a smaller size racquet.
    So totally wrong for a badminton racquet, because you can see that the stress goes up rapidly when you get to close to 3 and 9 o’clock.
    same for the 3 point inner support though.


    The major problem with the outside supports is that they are not adjustable anymore on the machines nowadays as they were earlier.

    So when a manufacturer would make a realy badminton machine the outside supports should be much closer to 12 o'clock.
    that may be true for some machines, but for many machines, the position of the side support is adjustable by moving the end columns.

    i was initially more convinced that the 3 inner support as advocated by you is much better. but now i am not so convinced anymore after gain understanding of the graph.

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