How to set your racquet up like an ATP pro

Discussion in 'Racquets' started by travlerajm, Jun 18, 2006.

  1. travlerajm

    travlerajm Hall of Fame

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    The ATP pro landscape is becoming more polarized. What I mean by this is that the ATP tour used to be the exclusive realm of players who played heavy racquets with low moment of inertia. Today, most pros still use the classic depolarized setup. But we are now witnessing the dawn of the “polarizer.” Polarizers use racquet setups with more polarized weight distributions - i.e., weight distributed more toward the ends.

    The polarized setup is used by players like Federer, Nadal, and Davydenko. Polarized setups have very low hitting weight to swingweight ratio. Because of the relatively low hitting weight, lower tension is required to compensate for the power deficit. The advantage of this type of setup is increased spin. So polarized setups are required to hit the ultra-sharp angles that Federer is known for (According to Greg Raven’s site, Fed’s racquet has a higher swingweight than a retail Tour 90, but it’s static weight is the same. It is therefore more polarized than the retail version). And Nadal’s polarized setup (15 grams under his bumper plus 5 grams in the butt) help him generate the tremendous spins that have helped him to dominate the clay court circuit.

    While polarized setups are becoming more popular today (especially for slow-court specialists) because of the increased spin potential, the polarized setups have some major disadvantages. The biggest disadvantage of the polarized (low-tension) setup is that it is very difficult to control the trajectory of your shot when the incoming shot has heavy spin. Considering Federer’s low-tension polarized setup, his inability to drive his flat backhand accurately when he plays Nadal should not be surprising. Also, a polarized setup has poor stability and control on volleys. Polarized setups make it more difficult to hit accurate powerful shots unless a heavy spin component is used to control the depth.

    Due to these many drawbacks of polarized setups, most pros still opt for classic depolarized setups. It is no coincidence that the best returners in history have all been “depolarizers.” Hewitt, Agassi, Blake, and Courier are/were among the best at stepping in and ripping returns on the rise. As good as Federer and Nadal are, these two polarizers will never be able to drive service returns from inside the baseline like the best depolarizers.

    In general, the best serve-and-volleyers have all been depolarizers. As depolarizers like Becker, Edberg, Sampras and Krajicek have shown, the lawns of Wimbledon are perfect for the accurate and penetrating balls that come off the stiff stringbeds of a depolarized racquet. Rafter is a notable exception – his polarized setup allowed him to hit slow, high-bouncing kick serves, giving him time to close tightly on the net. He then used his athleticism to stab passing attempts downward into the court. But Rafter’s springy stringbed was less than ideal for hitting the precision first volleys from shoetop level that were a key to Sampras’ and Becker’s Wimbledon dominance. And Rafter’s loopy serve didn’t bounce as high on grass, making it harder for him to dominate on grass the way he could on speedy high-bouncing hardcourts.

    So now on to the main point of this thread…

    The following step-by-step procedure will allow you to customize your racquet with a “depolarized” low polar moment of inertia setup so that it plays similarly to the racquets used by the majority of current ATP pros. Pros using this type of setup include Sampras, Agassi, Blake, Roddick, Hewitt, Kiefer, Grosjean, and most greats from past eras.

    Procedure for creating the classic “depolarized” pro style racquet setup:

    Step 1. Start with a thin-beam stock racquet. A flex rating of 65 or lower will work best. Stiffer platform frames will be excellent for serve-and-volley style, but the spin potential of stiff frames will be severely limited once they are properly leaded up. So I recommend starting with a flexible frame. The starting strung weight can be anywhere between 11 and 12.5 oz. Headsize is not critical.

    Step 2. Choose your desired final racquet weight based on your desired style of play. For serve-and-volley style or for an offensive-minded penetrating groundstroke style, I recommend 13.0-13.5 oz. When optimized, a heavier racquet in this range will be best for directional accuracy, especially against hard-hit incoming balls, or against heavy incoming spin. If you would prefer to be a little more defensive-minded or consistency-oriented player, I recommend a static weight closer to 12.5 oz. For best results, I recommend that there is 0.5 to 1.5 oz. between your starting strung weight and your desired final weight.

    An aside note: When choosing your playing style, I encourage you to be open-minded, ignore your current strengths and weaknesses, and select the setup of the player you most desire to play like. When I use a well-balanced, Federer-like polarized setup, I find myself going for inside-out sharply angled dipping forehands. When I set my racquet up like Coria, my strokes become loopy and spinny but I feel like it’s impossible to miss. But when I set my racquet up like Blake, I can’t resist going for flat penetrating forehands to the corners. And when I use the Sampras setup, my serve-and-volley confidence shoots skyward. In other words, my racquet setup influences my playing style more than my physical skills do. Unless you have an obvious physical limitation, your game may be more versatile than you think.

    Step 3. Add lead at 3 and 9. I recommend adding about 5-10 grams total (about 5 grams for starting stock swingweight of 330, plus an additional gram for every 5 kg-cm^2 drop in stock swingweight below that) with two layers of strips on each side. It is better to use 2 layers of 4" strips than to spread one layer over an 8-inch length because the former will increase swingweight less. Also, significantly better torsional stability can be achieved by putting the lead on the outside of the frame rather than the inside, since the change in moment of inertia about the longitudinal axis is proportional to the square of the distance from added lead to the centerline. Use ¼”-wide strips on each side of the string plane. Eight grams is a rough guideline. The total amount that you add here can be adjusted later when you troubleshoot your setup. But I definitely advise against adding more than 10-12 g at this location, since the swingweight will likely become unmanageable.

    Step 4. Measure the new weight and balance of your racquet.

    Step 5. Calculate the amount of additional weight to be added using this equation:

    m’ = M – m

    m’ = additional mass to be added, in ounces.
    M = desired final static weight in ounces.
    m = static weight measured in step 4, in ounces.

    Step 6. Calculate final balance point using this equation:

    R = 44.57 / sqrt(M)
    R = distance to final balance point from butt end.
    M = desired final static weight.

    Step 7. Calculate location to add concentrated mass m’ using this equation:

    r’ = (MR – mr)/m’
    r’ = location of center of mass for m’, in inches from butt end.
    r = distance to balance point in inches measured in step 4.

    Step 8. Add mass m’ at location r’ by wrapping lead tape around handle (under grip). Make sure that the center of mass for m’ is within 0.1” of location r’. As other racquet technicians such as John Cauthen have correctly noted, the location of this mass is critical to having a high-performance setup. The value for r’ determined by the above equation will optimize the plough-through effect of the racquet for a male player of normal strength. Moving the mass m’ a quarter inch up will likely decrease power due to higher swingweight, while moving it a quarter inch down will likely decrease power due to lower hitting weight. For best results, the total width of the leaded zone centered around r’ should not exceed 1 inch.

    Step 9. Adjust tension. This depolarized leaded setup may be higher powered than your regular setup. If so, an increase in string tension will be required to optimize control. For final weights around 12.5 oz., you likely will be fine with the tension that works for you in the stock frame. But for setups over 13.0 oz., an increase of 5 lbs or so will probably be necessary.

    Step 10. You are ready for a playtest.

    Step 11. Troubleshooting your setup:

    If your frame feels overpowered or underpowered, there are two preferred options. The first option is to adjust the string tension. Another option is to adjust the desired final static weight and repeat steps 2 through 8. If your racquet is overpowered, a lower static weight will reduce the power. And if it is underpowered, increasing static weight will help.

    You can use the amount of weight at the 3 and 9 region to tune your swingweight. Increasing the weight at the 3 and 9 region will flatten your serve and groundstrokes, while decreasing the weight will add spin. I recommend making these adjustments in 1 gram increments. Also, you might get better results if you repeat steps 2 through 8 after you tweak the amount of lead at 3 and 9.

    Lastly: remember that these are just general guidelines to get you started on your way to a sweet feeling setup that will best suit your game. Don’t be afraid to keep tweaking things.

    -----------------

    In the future, I plan to contribute some guidelines to customizing your racquet with well-balanced polarized setups also. I have so far designed a number of well-balanced polarized setups with specific frames. But polarized setups are more sensitive to the weight and balance of the starting platform frame, so it is more complicated to devise a general template like the one above.

    Also, please understand that I will not be hanging around to read TT posts anymore, so don’t take it personal if I don’t respond to a question.
     
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  2. mutt

    mutt Rookie

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    What you means by polarized and depolarized?
     
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  3. dmastous

    dmastous Professional

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    My guess is a depolarized racquet is one that is evenly balance. Neither head light or head heavy.
     
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  4. mislav

    mislav Semi-Pro

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    I understood the terms polarized and depolarized as in having the weight of the racquet distributed either on each of the ends or more equally throughout the length of the racquet.
     
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  5. jackcrawford

    jackcrawford Professional

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    Check the ATP stats - Nadal is the best returner around.
     
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  6. ohplease

    ohplease Professional

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    So why don't Federer and Nadal play a similar style?

    travlerajm continues to have bits of good advice here and there - but the whole "rackets are destiny" argument continus to wilt in the face of even the most mild reality checks.
     
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  7. louis netman

    louis netman Hall of Fame

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    Grab two identical frames that have been modded to increase static weight. For example both are 13 oz. #1 is tweaked to be "Polarized," it's less HL (e.g. 13 oz 4pts HL). #2 is tweaked to be "Depolarized," it's the same static weight, but more HL (e.g. 13 oz 10 pts HL).....as a result, swingweights will be considerably different.
     
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  8. travlerajm

    travlerajm Hall of Fame

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    This is not correct. If two 13-oz. frames have the same static weight and same balance point, then then the one that is more polarized will have the higher swingweight. It would not be possible to play at the ATP level with a 13-oz.+ racquet unless it is "depolarized" to have low polar moment of inertia, because the swingweight would be too high otherwise.

    The degree of polarization has nothing to do with how HL a frame is.
     
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  9. kabob

    kabob Professional

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    Then to what does degree of polarization refer? Sorry, I'm not an engineer, please explain in layman's terms.
     
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  10. sureshs

    sureshs Bionic Poster

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    Hey you are back. Very short retirement.
     
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  11. Ztalin

    Ztalin Guest

    Polarization is a term that he's using to represent the concentration of mass on a body. For instance, is the weight concentrated on an object's outside (ends), or middle, or is it evenly balanced? Weight at the outside of an object leads to a higher moment of inertia. This is what he's referring to with polarization.
     
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  12. louis netman

    louis netman Hall of Fame

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    I have a Volkl C9 at 12.8oz and 12 pts HL and a Tour 10 MP also at 12.8 and 12 pts HL.....The Tour 10 feels like it has higher SW (don't know exactly as I can not fit my modded butts into the RDC SW machine). Am I correct in saying that the T10 MP has a higher degree of polarization (more polarized)?
     
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  13. Z-Man

    Z-Man Professional

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    Yeah, I'm lost too--explain what makes a racquet more or less polarized. My sunglasses are polarized. Political parties are polarized. I think you're on to something here, but I can't decide if it's something real or if it's like "A Beautiful Mind". Is a polarized racquet head-heavy? Is the weight more concentrated in the ends? I agree that different setups encourage different types of play.
     
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  14. kabob

    kabob Professional

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    Okay, so explain how that applies here to racquet technology?
     
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  15. The Ripper

    The Ripper Semi-Pro

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    I've read a lot about the weighting of rackets but never heard anyone use the term "polarization" or "depolarization" to describe anything about a tennis racket. Why can't this be discussed in customary terms like headlight/headheavy, swingweight and static weight? Has anyone else heard of a "polarized" racket?
     
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  16. louis netman

    louis netman Hall of Fame

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  17. louis netman

    louis netman Hall of Fame

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    Thought it would be a fun experiment, but it wouldn't pan out for me anyway. After I add my birch bevels, leather, overgrip and tape to expand the butt, I'd have no more margin to add the polarization mass to point R on the handle.... unless I started out with a 9 or 10 oz racket, of course. Anyone know of any flexy 9 or 10 ouncers?


    BTW, in the mod step #2, I think target swingweight would be a better goal to strive for over target static weight...
     
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  18. Ztalin

    Ztalin Guest

    Because somethign with a higher moment of inertia will produce more rotational momentum, and therefore transfer more momentum onto the tennis ball.

    Rrotational momentum = I*rotational velocity.

    I=rotational inertia. It's a measure of how far the average weight of a rotating object is distributed from its center.
     
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  19. MTChong

    MTChong Professional

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    Not sure if it is that light, but I remember the specs of the nFury indicating that it is really flexible and light.
     
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  20. kabob

    kabob Professional

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    I don't want a scientific explanation, sheesh. I want to know how polarization is important in a racquet, what areas of the racquet we're talking, how exactly you're supposed to be modifying the racquet and, finally, how this all affects play. What does weight distribution mean to an object with a rounded hoop and a handle?
     
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  21. Zverev

    Zverev Professional

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    Prince's "Thriple Threat" technology would be a fine example of polarised weight distribution.
    Polarised technology is great, but obviously more expensive.
    IMO, manufacturers are still at very primitive level of racquet technology.
    When they will be capable of making a racquet with optimal weight distribution for specific criteria, and at managable cost, call me.
    For that they need new kind of materials, where they can manage strenth and density, and flex of any specific point of racquet body.
    So far all their "technologies" besides graphite are gimmicks.
     
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  22. HyperHorse

    HyperHorse Banned

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    thanks for the insightful post....
    makes a lot of sense, particularly when you talk about Federer...
     
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  23. Ztalin

    Ztalin Guest

    How about you do a little research... look up what inertia is on wikipedia or something. I explained it to you how I know how to. Not my job to do everything.
     
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  24. kabob

    kabob Professional

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    Then why bother saying anything? You didn't say a word that I could apply in terms of tennis :rolleyes:
     
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  25. Ztalin

    Ztalin Guest

    You don't know what momentum is? MORE momentum on the ball? Do I need to quote myself? Here, I'll give you a definition.

    Momentum: The product of the mass times the velocity of an object.

    In layman's terms: Higher inertia = more momentum on ball = higher ball speed!

    I don't mean to be a dick, but I "didn't say a word that I could apply in terms of tennis?"

    You don't understand how momentum transfer applies to tennis? Momentum of a ball? Oi...
     
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  26. Woodstock_Tennis

    Woodstock_Tennis Rookie

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    Interesting post, but think somethings wrong.

    My Racquet is 360g (12.857 oz) and a balance point of 12....

    If I want to achieve 13.6 onces as a finishing weight your equations gives you an r' of 19, which is way past the point of the handle.

    Edit: might be a little off, did it that in my head

    But using my real racquet which is 360g and a 11.5 balance point, if I want a finishing weight of 13.5 you get a r'=24.
     
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  27. kabob

    kabob Professional

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    Holy crap, I KNOW WHAT PHYSICS IS, I TOOK COLLEGE PHYSICS IN HIGH SCHOOL. What I'm not understanding is how this weight distribution thing is being enacted on a tennis ball during play and what modifications you can do to the racquet to enhance play.

    Or maybe I just tuned out the first post in this thread. Oh well.
     
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  28. travlerajm

    travlerajm Hall of Fame

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    You will not be able to depolarize your racquet without first removing the weight that you have added to the handle (your starting point is 16 pts HL!).
    Your extremely low balance point means that you are starting with too much weight near the butt, which is inefficient for power generation. The goal of this type of weighting is to maximize the efficiency of any added weight.

    The equations are correct. If you start with an unmodified stock racquet, r' will usually be between 6 and 9 inches.
     
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  29. Woodstock_Tennis

    Woodstock_Tennis Rookie

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    Everyone should try this...
     
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  30. sureshs

    sureshs Bionic Poster

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    The specs of the new Slazenger NX1 were posted on another thread, and it is a good example of the move to polarization in player's racquets. Lighter and bigger head than the Pro X1 it will replace, along with a HH balance.
     
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  31. Roforot

    Roforot Professional

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    Agree w/ many of the above posts, "polarization" as it applies to a tennis racquet is not clearly defined by the OP. Does it refer to headlight? Apparently not? How does one know if a racquet is polarized or depolarized?
     
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  32. travlerajm

    travlerajm Hall of Fame

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    I added a brief definition of "polarized" in the OP. A racquet is more polarized if the weight is distributed more toward the ends. A racquet is less polarized (or "depolarized" ) if the weight is distributed more toward the middle.

    To summarize, if two racquets have the same weight and same balance, but one is more polarized, the more polarized frame will have higher swingweight.

    And, if two racquets have the same balance and same swingweight, but one is more polarized, the more polarized frame will have lower static weight and lower hitting weight, which translates to lower power level. Thus, the more polarized a racquet is, the lower the tension must be to compensate for the lower power level.

    And, if two racquets are set up and strung with the same weight, same balance, and same power level, but one racquet is more polarized, the more polarized setup will generate more spin but less directional accuracy.

    I hope this clarification helps.
     
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  33. Roforot

    Roforot Professional

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    Ah, thanks a lot, this explanation adds a lot to my understanding! And this adds another dimension in choosing racquets.

    My standard frame now is a Yonex SRD-Tour 90; I had built the grip up 2sizes as well as added some weight to the head of the frame; hence leading to a Polarized setup... and your observation is correct... I am able to whip off some great angles and spin even compared to other spinfriendly racquets like the PD+...

    The other racquet that I've been tinkering with is an o3 Tour MP... I believe this frame is more depolarized, and I enjoyed groundstrokes w/ this racquet, but not serving... From reading on this forum, other people had improved this by adding lead. I choose to add lead to the throat b/c I didn't want to mess w/ the O-ports or make the racquet headheavy... further depolarization. I will test the effects of my adjustments this weekend. Depolarization is favored by S&V, does that mean it tends to make racquets easier to serve?

    Thanks again for your input.
     
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  34. travlerajm

    travlerajm Hall of Fame

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    It's not quite that simple. Here are some more guidelines:

    Heavier racquets are better for volleying because they are more stable; and maneuverability (low swingweight) is better for volleying. A depolarized setup allows the racquet to be much heavier while still maintaining a relatively low swingweight. Thus, depolarized setups are better for volleys. Also, depolarized setups allow higher tension, which gives better directional accuracy on volleys.

    A depolarized setup is best for flat serves or very hard spin serves because it maximizes power for a given swingweight while maintaining directional accuracy. However, a polarized setup would be better for an American twist serve, because that type of serve requires lots of rpm to be effective. Most of the best hard servers like Sampras and Roddick use more depolarized setups, but Arthurs and Rafter prefer more polarized setups because they rely more on spinny kick/twist serves rather than power.

    A racquet that is best for your serve is a racquet that has a swingweight that matches your strength. Most people can serve hardest with a swingweight in the mid 340s. If your swingweight is too low, it will reduce your accuracy as well as power. But a swingweight too high will also reduce your accuracy and your ability to add spin to your serve.
     
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  35. Povl Carstensen

    Povl Carstensen Legend

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    I guess polarisation is what John Cauthen talks about when he says bipolar massdistribution. In his case he advocates weight in the top of the handle and at the top of the hoop. I think it works, but have not gone to the extremes of adding 40 grams or so at the handle. I also think that some rackets need a little weight at 3 & 9 for torsional stability.
     
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  36. ACK4wd

    ACK4wd Rookie

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    I'm a little confused by how to adjust a raquet to this formula for improving serve and volley. For example a lighter raquet like a Babolat VS NCT Control 9.6 oz & 4.2 pts head heavy - would I be aiming at quite a bit of leading up? I couldn't imagine playing with a static weight over 12& 1/2 oz. Under this formula what would be the result of final specs. I would be greatly honored by your assistance travlrajm.
     
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  37. Amone

    Amone Hall of Fame

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    I would have to agree with ACK, though not in the weight comment, in that it would be GREAT to hear how to set up a racquet for SV. I've been running through some of your theory, TravelerJam, so when I'm all done with that, I'll get back to you on the results of my tests. Right now I'm still in the prep stages, and then it'll be a few weeks before I can be totally finished. But if you could get some idealized SV specs, then I'd be much obliged, because I don't enjoy the baseline game that your specs would most likely aide, and I would prefer the final word what I should be using to increase my happiness in that respect when the time comes.

    Admittedly, you say that the current setup is great for SV, but I just wanted to make sure, because I would certainly not want to shortchange you by using the wrong theory.
     
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  38. travlerajm

    travlerajm Hall of Fame

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    I've tweaked the instructions in the OP so that the weight added to the hoop will take into account the starting stock swingweight. For best SV results, apply the formulas and shoot for a static weight in the neighborhood of 13 oz.
     
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  39. travlerajm

    travlerajm Hall of Fame

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    the idea behind "depolarization" is to make your racquet heavier with minimal increase in swingweight. This is ideal for SV because you want the heaviest racquet that you can still handle. If you follow the instructions and aim for a racquet setup over 12.5 oz., your volleys will be much much easier to control. If you are used to a 9.6 oz. racquet, you may need to adjust your technique, since you are probably accustomed to swinging at your volleys or even "wristing" a bit to generate power. After you add several ounces of lead, you will simply need to put the racquet in front of the ball and let the ball bounce off it - a much easier way to control your volley (You may need to ditch the wristy habits that your light racquet gave you).

    BTW, here's the first feedback for this setup posted by a forum member who tried it:

    http://tt.tennis-warehouse.com/showthread.php?t=105956
     
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  40. ACK4wd

    ACK4wd Rookie

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    travlerajm - just a little more help for a math plebicite

    I think you've discovered the phi for racquets, travlerajm - okay you only live once - 'm in, i'll try the extra 1/2 oz to 13

    starting weight 9.6 0z w/298 swingweight

    i'm to add aprox 10 grams at 3&9 no more than 4" strips (preferably on the outside of the frame) & then lead up to 13 oz

    here's my math so far:

    m' = 3.05 oz
    M = 13
    m = 9.6 oz + 10 grams (0.35oz) = 9.95 oz

    R = 44.57 / sqrt (13) = 12.3615
    r' = (13*12.3615) - 9.95*r)

    stuck on r --> Mathamatically, if I'm starting out 4.2 pts head heavy & I attach the 4" lead exactly centered @ 3&9 what would be the value of r?

    I'm using signum ppp 17 does that effect the values?

    I how would i calculate this?

    And heck yes to replacing those squash shots - cheers by the way, that you are back.
     
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  41. travlerajm

    travlerajm Hall of Fame

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    You can simply measure the balance point r by balancing your racquet on the edge of a ruler, then measuring the distance from the butt end to the balance point. I'll do the calculation by estimating that r = 14.25", but it's better to measure it. (I estimated it by assuming that the center of mass of the added hoop weight is at 21" from the butt, so r = (298*14.025+10*21)/(298+10) = 14.25".

    r' = (MR - mr)/m' = [(13*12.3615) - (9.95*14.25)/(3.05) = 6.2"

    I would suggest using 2 layers of 5" strips at 3 and 9.

    Since 3.05 oz. is a LOT of lead = 86.5 g = 173" of lead tape, you'll have no choice but to spread the handle lead out a little bit. If you have a one-hander, a bulky lump at 6.2" would not be a problem, but if you use a 2hb, I would recommend dividing it into 32 strips of 5.4" length. You should be able to fit 8 strips side by side on the handle under the grip, so you would have 4 layers. Or if you want a flatter grip shape, you could use 2 strips side by side on each edge with 8 layers. Or perhaps use the the Cauthen method and use thicker lead sheeting? Or maybe sand down your grip first before you apply the formulas?
     
    #41
  42. louis netman

    louis netman Hall of Fame

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    I used the formula for a Volkl C8 and C9. My usual setup is about 12.9 oz & 12-14 pts HL. My new "formula" rackets felt much heftier than my previously modded C10s and were 12.9oz and were about 7-8 pts HL, a significant increase in SW...

    Test results: I'm currently injured and my groundies were clocked at 90-100mph and waaay flatter than normal. There was some windscreen damage on the receiving end of the court. Serves were 120's with little effort. I was sticking volleys into the ground. Important note: I will not be able to carry this lumber effectively throughout an entire match. End of experiment.

    Travlerajm: Now that I have located r, can I reduce the weight to get it into my SW comfort zone (very important to my on-court effectiveness)? I realize that r changes when the target static wt changes, but will I attain any benefit from adding ANY weight to previous r (which ended up being slightly above the handle on both test frames)?
     
    #42
  43. travlerajm

    travlerajm Hall of Fame

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    There are three good choices that you might try. The 1st option is to keep the static weight the same, but further depolarize your setup. You can do this by subtracting a few of the added grams from the hoop, then recalculating a new r' (which will be more in the throat region). Thus your static weight and balance will be the same as before, but you swingweight will be lower. Your power level won't change too much, but you'll lose a little torsional stability on volleys.

    The 2nd option is to keep the same weight in the hoop, but shoot for a lower static weight. The problem with this option is that most of the added swingweight comes from the added wt at 3 and 9, so you won't be able to drop the SW that much.

    The 3rd option (probably the best) is to combine the first two options above. Thus, maybe try for 2 fewer grams in the hoop, and then shoot for a static weight of maybe 12.6 oz., and then apply the formulas.
     
    #43
  44. Punisha

    Punisha Professional

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    OK, i understand all the theory to this, but customizing my RDX mid (11.8 ounces) to 13 ounces??? How do i go about that???
     
    #44
  45. gerli

    gerli Rookie

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    Jun 16, 2004
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    Calculate R

    Please help me with the calculation of R.
    In your example R=44,57/sqrt(13)=12,3615 how do you came to 12,3615???
     
    #45
  46. GroundMaster

    GroundMaster Banned

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    travlerajm, depolarization sounds like a very interesting concept. I'm definitely interested in increasing the mass of my racquet to help on volleys, but do not want to aggravate my old TE injury on groundies.

    I must go and digest this thread further to work out my setup.
     
    #46
  47. ACK4wd

    ACK4wd Rookie

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    I think I can help:
    R equals the constant (44.57) divided by the square root of the target weight in ounces - the square root of 13 by a calculator is 3.605.
    So 44.57 divided by 3.605 is roughly 12.3615
     
    #47
  48. fast_server

    fast_server Guest

    Hey - This really works!

    I've been reading these posts & other posts about where to add lead and why. This stuff is great. The man is 100% right on. I just jumped up from the lower rung to the top. I've worked hard to break in the lower ranks for the past 5 years. This guys a freaking genius. I have racquets set up for conditions & the type of player that I'm playing and because of my level of play I have enough racquets to do this. He's right on the mark - this is exactly what has jumped my game above the juniors. Take it from someone who's sponsored, balance your racquet according to physics and practice. This really is an amazing formula. Sorry, if i don't respond much, I've got to get back to the courts.
     
    #48
  49. tennis_nerd22

    tennis_nerd22 Hall of Fame

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    one sec, i'd be careful to believe this post guys. he's a new user, and this was his only post, travlerajm might have made up the new user... just be careful
     
    #49
  50. looseswing

    looseswing Professional

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    So if we try this formula we would be reducing our spin? That might be a problem for me because I hit with pretty minimal spin as it is.
     
    #50

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