Swing Weight App for Ipad (video)

Discussion in 'Racquets' started by luishcorreia, Jan 18, 2012.

  1. luishcorreia

    luishcorreia Professional

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    I've used the SwingTool App to measure racquet swing weight on iPad.

    Here are the photos and videos.

    http://online-tennis-blog.blogspot.com/2012/01/measuring-swing-weight.html

    I meassured my strung Wilson BLX Blade 98 and got a value of 325 (Tennis Warehouse states that the swing weigh for this racquet - strung - is 335).

    Close enough?


    Also, I did it several times and got very proximate results.
     
    #1
  2. kybb

    kybb New User

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    I got curious and measured 2 BLX Blade 98 rackets with this app.

    Results are here (strung+overgri and no dampener):

    Swing point..............Racket 1....Racket 2
    10 cm.......................332g.........327g
    9 cm.........................348g.........344g

    Racket weight............329g.........328g
    Racket balance..........32,8cm......32,7cm

    I measured also by changing swingpoit to 9cm beacause i have tendency to hold racket from the very end of the handle and this changes a lot.

    Because TW uses a method with what they mesure several rackets and they calculate medium results then I would say that there can be wery big difference between higher and lower SW results because one of these frames that I mesured have 4g added to the handle to bring it specs wise closer to the other frame. Before that they were 5g and 4mm different.

    I would say that this app can be quite accurate.
     
    #2
  3. luishcorreia

    luishcorreia Professional

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    I think the most interesting application of this app would be to measure changes in swingweight when adding weight to the racquet.. and not getting the EXACT swingweight..but just measuring the differences..
     
    #3
  4. Maui19

    Maui19 Hall of Fame

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    Wow I am envious you found this app this so easy to use. I bought SwingTool for my iPhone and I find it about 10,000 times harder to use than the TW swingweight calculator. In fact I got zero usable results and ended up just going with the old fashioned way. Oh well.
     
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  5. Anton

    Anton Hall of Fame

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    Do you know what swing point TW uses? 10cm?
     
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  6. corners

    corners Legend

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    Are you comparing the number you got from TW to the measurement of your actual frame? Close enough? The TW number is an average of five different racquets. They take an average because swingweight varies widely from stick to stick. So what this means is that your Blade 98 has a swingweight lower than the average Blade 98. You can't evaluate the accuracy of the app by comparing it to the TW average. What you are really seeing is variation between racquets and Wilson's quality control (or lack thereof).

    This app has been discussed on these boards quite a bit and the consensus is that it is very accurate. But to be accurate, your measurements of balance, static weight and the distance from the butt to the string you swing it from have to be exact. If you do that it should be plenty accurate.
     
    #6
  7. luishcorreia

    luishcorreia Professional

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    excellent question.. :-|
     
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  8. sparkyS4

    sparkyS4 New User

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    RDC machines use 10 cm, I believe that TW uses the RDC machine. I have found the swing weight app to be very accurate. My rackets measure 332 on my friends RDC machine, whereas I consistently get 332-334 with the app. I also had a fabricator friend of mine make up a jig, so I found that my results are very consistent.
     
    #8
  9. Anton

    Anton Hall of Fame

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    a jig for what? hanging the racket?
     
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  10. sparkyS4

    sparkyS4 New User

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    Yeah, it holds the racquet and the ipod touch, it allows for different string spacing and also allows for the 10cm swing of the racket. I did a mock up out of wood and made adjustments, then the fabricator did it out of steel. It's heavy, but I didn't need it to be portable.

    The reason I went through the trouble is that I was getting different values with the same racket when I used the table/book/pencil setup, I also had issues with my racket staying on the pencils, probably because poly is slippery. Anyway, I get very consistent results with this set up, so it was worth the effort for me.
     
    #10
  11. JackB1

    JackB1 G.O.A.T.

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    yes pencils don't work that great...the racquet slips and slides a little when the racquet is in motion.
     
    #11
  12. sparkyS4

    sparkyS4 New User

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    I used steel dowels for my jig and had a groove cut in them with a lathe so the string can seat and the racket still swings freely.
     
    #12
  13. Anton

    Anton Hall of Fame

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    Pics or it didn't happen! :)
     
    #13
  14. ohcaptain

    ohcaptain Rookie

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    Got consistently using the app:
    Wilson k factor six-one 95: 336 (very close to TWA value, 338 )
    Tecnifibre t-fight 320: 311 (quite different from TWA value, 324)
    (considering weight from strings, anti-dampener and overgrip, and balance considering them)

    and swingpoint = 10cm
     
    Last edited: Dec 30, 2012
    #14

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