How much weight equals how much balance change?

Discussion in 'Racquets' started by wolfpackfive, Mar 10, 2005.

  1. wolfpackfive

    wolfpackfive New User

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    In general, how much weight at 3 and 9 o'clock equals how large a balance change. For instance, would 3 grams at 3 and 3 grams at 9 (6 total) make a 6 points head light racquet even balanced? Probably not so simple and depends on the overall starting static weight as well as its distribution throughout the racquet, huh?
     
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  2. Steve H.

    Steve H. Semi-Pro

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    Here's the formula for shift in balance point

    shift = d*m/(m+M)

    where M = mass of the frame (g)
    m = mass of the weight added (g)
    and d = distance from the balance point you add the weight

    hope this helps
     
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  3. gregraven

    gregraven Semi-Pro

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    Uhh, Steve H., he asked for an answer in general, not in specific. :)
     
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  4. tedmeister

    tedmeister Rookie

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    In General, the lighter the frame, the less weight it will take to move that balance point. In Private...that will take some time, a lot of math and a calculator among other things :mrgreen: Better to just visit our shop for a free consultation.
     
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  5. Steve H.

    Steve H. Semi-Pro

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    That formula _is_ the general answer, guys, and it's not rocket science. By all means go to a shop if you want, but you can learn more just fiddling with your own frames.

    You can approximate without a calculator: let's say the racquet is 300 grams and 6 points (2 cm) head-light. You add 6 grams about 20 cm from the balance point

    so the balance shift will be 20*6 / 300+6 = 120/306 = about 0.4 cm
    (a point or two, still nowhere near even balance)

    In general, if you want to alter the balance of your racquet adding tape to the hoop isn't a great way to do it because it will make a much bigger difference to swingweight than to balance. Adding or removing weight at the handle, however, will have an equal effect on balance but won't change swingweight much because the handle is at the axis of rotation.
     
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  6. rich s

    rich s Hall of Fame

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    Steve- I'm with you!

    You can't get much more general than that.
     
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  7. Kaptain Karl

    Kaptain Karl Hall Of Fame

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    Steve - Thanks! I've "suspected" there was a formula to gauge what weightings would do. Knowing this, I may even try tweaking my frames this Spring.

    - KK
     
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  8. tedmeister

    tedmeister Rookie

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    There are some folks out there where you really have to whip out the tools of the trade such as the balance board and scale before they will be satisfied. They want the numbers to look right before they start having confidence in the stick. I've used the racquet customizer tool for my own racquets before, the numbers looked right but it somehow doesn't feel right. I still had to do some minor adjustments to get it to go through the air like I wanted.

    If one takes a closer look at Steve's formula. the smaller the mass of the frame which is the denominator in this formula, the larger the shift in balance will be which was my point in my first post. This quantifies what we know for a fact from experience that it is so much easier to customize a lighter frame than a heavier one. I was half kidding when I mentioned that we'll be needing a calculator to compute this :grin:
     
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