Racket Customization

From talk tennis.com forum
http://tt.tennis-warehouse.com/showthread.php?t=295789


Well, once we reach a certain point in our games, we have pretty dang big groundstrokes. Most rackets are in the SW1 category (the lower swingweights). Moving them up to SW2 status (high swingweights) adds control to our swings, as well as giving power and spin. No matter what, adding weight will pump up the swingweight (albeit to different levels based on WHERE you put it).

So basically, everyone that plays tennis on a high level and uses custom weighted rackets is eventually going to end up playing with ridiculously high swingweights (okay, ALMOST everyone; Verdasco is one of the exceptions). The difference is HOW they want to get there. Some people want rackets that are insanely stable and plow through the ball, giving insane amounts of power and control for anybody good enough to swing it around (like Sampras, Roddick, and Courier). Others like the rackets to be very easy to whip around, allowing them to use heavy amounts of wrist action in their shots and allowing them to generate unprecedented amounts of spin (like Rafter, Nadal and Federer).

To get insane amounts of stability and plow through on the ball, you need VERY high levels of mass on your racket so that you can barely feel the ball's "weight" on contact (you can still feel the ball extremely well, but you might notice a more muted response than before thanks to the added stability). But the more mass we add, the higher the swingweight. So if we do it wrong, we won't get as much mass as we want, and we'll already reach our ideal swingweight in the SW2 section. So these people will put the weights lower on their racket (closer to the center of the racket; 3&9, as well as around the throat or top of the grip for counterbalance). That way, they can put more weight on their rackets to reach the amount of power and plow through they want without exceeding their ideal swingweight specification. This is what we call a depolarized setup. It's what most pros used. 95% of pros (if not more) prior to the year 2000 used this kind of setup. A wood racket is essentially a depolarized racket, so 100% of people prior to graphite rackets used a depolarized setup.

Others like their rackets to be less hefty, while still having that nice, high swingweight. To do that, they want every bit of mass they add to increase the swingweight as much as possible, so that they add very little mass to the racket, but get that nice spike in swingweight. They will end up putting the weight near the top of the racket (under the bumper guard) and some inside the buttcap for counterbalance. But since at this point, people don't care too much about balance, most of the added weight goes under the bumper guard (I hear Nadal adds 9 grams under the bumper and 2 in the buttcap while all of Federer's added racket weight is under the bumper, which I'm guessing is 2.5-4.5 grams). These rackets have lower static weight and become more manageable and spin friendly. Also, since the weight is mainly distributed towards the ends of the rackets, it spins on it's axis better, allowing for even better access to spin and racket head speed. This is what we call a polarized setup. Nowadays, a lot more people are using this setup thanks to the lighter rackets out there. Also, this is the reason why we will see some pros with a ridiculously low racket mass.

Now, which setup is the best? That's up to personal preference, as stated before. I love both (currently using/trying a slightly polarized setup like Federer). A depolarized racket is the more conventional type of racket customization (as it's been around longer) but it's a little more difficult to do (overall, but it depends on the racket as well). It grants extra forgiveness, stability, and pop so most people should generally look to have this kind of setup. It's the best for aggressive baseline hitting, as well as for serve and volleying. If you want to take the ball on the rise, or are an aggressive returner (like Agassi and Blake; both of whom use a depolarized setup), then you'll love the stability and power this setup gives. The other one is better for people who feel like they have all the power, forgiveness, and stability they need, but are lacking in some spin and margin for their shots. This is where a polarized setup can help, because it really adds a lot of spin to your shots and gives you extra margin over the net to safely stay in points. Nadal uses this setup to great effectiveness, employing heavy spin off the forehand and serve, constantly pulling his opponents wide and out of position. Rafter liked it because his big weapon was his kick serve and athleticism. A polarized setup added extra kick and action to his serves. He would kick a high one up to the opponent's backhand, then use his athleticism and feel for the ball to put away volleys. Though, this caused him to be less effective on grass, where serve and volleyers should dominate (as you can guess, almost all serve and volleyers use a depolarized setup). However, I must say that I found the polarized setup to be more erratic overall. It becomes difficult to control the racket sometimes (because the power and spin might not always be as consistent due to lack of stability), but most of the time you'll get good results if you like to use heavy spin.

The depolarized racket doesn't put all of the weight in the handle. It actually has most of the weight in the head at 3&9. This will add the power and overall plow through we are looking for in out groundstrokes. As counterbalance, we add some (or a lot, depending on what you feel works best) weight around the throat or the top of the handle. Someone suggested 7 inches above the buttcap, which works extremely well in my opinion. There is also an equation to find the "perfect counterbalance point" somewhere on this forum is you look up "How to depolarize your racket". I've added 20 grams at 3&9 and 14 grams at 7 inches above the buttcap on one of my K90s and it plays very well and has tremendous plow through with only maybe 10-15 more SW units compared to my polarized 12.5 ounce Yonex RDS 003.

If anything, a depolarized racket and a polarized racket can have the exact same balance and swingweight, while the depolarized racket can have far more mass.

Given two light rackets, I can easily produce two rackets with the same swingweight and balance, but the mass on the depolarized racket can be higher by about a full ounce, if not higher! One will produce noticeably more spin, while the other more power, stability, and plow through.

When making a depolarized racket, we're looking to increase swingweight as well, just in a far more conservative matter so we can add more effective mass without raising swingweight too rapidly, which will limit the amount of mass we can place on the racket. If you put all the weight in the handle, the center of mass will be so low that you might as well hit the ball with the handle instead of the strings. There really is no point to having an excessively headlight racket. Power comes from having weight in the head, and maneuverability comes from having weight in the top of the handle as counterbalance (how far up or down depends on the player).

You more or less have two basic options when adding 15 grams of lead to the head. You can put it under the bumper guard around the top of the hoop, or layer it at 3&9. Layering it at 3&9 will produce more power, while having it under the bumper gets it moving around faster (which is why I said it's more erratic overall, especially since to hit a good shot you need a loose arm). If you layered the lead at 3&9, the swingweight will be a little lower, and the racket will be more maneuverable, so you can add more weight (either at 3&9 again, or around the throat or handle as counterbalance) until the swingweights are matched. At this point, from the physics equations of F=MA and Momentum=MV^2, we can tell the new racket has far more power, stability, and plow through (it can more easily drive through the ball because it's more stable and has more power through contact). Also, since the weight is lower and closer to your hand, you can more easily control and direct the weight of the racket during the swing, allowing for better control and a more consistent contact (whereas the polarized racket can get all whippy and out of control sometimes).

When adding lead tape to the frame, you must always add lead to the head. There is no point to adding lead in the buttcap alone. It does nothing. It raises the swingweight (slightly), lowers the center of mass, raises mass in the most pointless manner, and it's biggest effects are mostly mental, where since you think your racket is more headlight, it will be more maneuverable. It will give you more heft in your hand when holding it, but it won't translate into power into the ball. To do that, you need the lead to be placed farther up and away from your hand. This is why I feel that adding weight to a head heavy frame is pointless. You can counterbalance it all you want by adding lead at the top of the handle, but you're better off finding a new racket that's headlight. You want to be able to add more weight to the head than to the buttcap/handle/throat. It's not always going to happen, but if you want the biggest power boost, that's how it's going to have to be.

When you add weight to the hoop, the mass isn't behind the ball. When you add it to 3&9, it's right on the center of the strings, allowing the weight to most effectively respond and react to the ball and push through it more effectively. This is where plow through comes from. Adding it to the top merely increases racket head speed due to a whippy feeling you get during the swing similar to a ball at the end of the string. The best description would be comparing a stick with a ball of mass at the very far end of the stick. To accurately control the stick with precision while swinging full force, more focus and strength is required. If you let it go (loosened up your arm/hand), the mass will pull the stick in the general direction your swing left it off at. Then if you swing a stick with the ball of mass in the center of the stick (or at least closer to your hand), it's easier to more precisely control the stick no matter how fast you swing, even with a loose arm and grip. This is why a depolarized racket has more plow through and stability (aside from the fact that weight at 3&9 help increase torsional stability; AKA resistance to twisting at impact), the weight is easier to precisely control and get behind the ball. This is also why (as I've said numerous times; sorry about that) a polarized racket is overall more erratic. If your swing is off by a little, the mass at the top of the frame will keep the racket going in that direction, magnifying your swing error. The spin it generates will keep it from going long most of the time, but it's still pretty inconsistent.

Headlight balance is great for intermediate players, but once you want some serious pop on your strokes, and your lightweight 11-12.5 ounce rackets don't generate enough punch anymore, you're going to have to sacrifice some of it for power. Once you reach 5.5+, balance doesn't matter, weight distribution does.

The reason people liked the K90 more than the previous Tour 90s was because of the newer weight distribution, which made it feel more maneuverable, have more pop and plow through, and go faster through the air even with the higher swingweight. And the reason people like the K88 more than the K90, is because the weight was reworked again, in such a way that power and spin are even more accessible regardless of the higher swingweight and mass! (You'll notice that even if you depolarize your racket heavily to such a degree it's meant only for flat hitters, you'll still find plenty of added spin thanks to the improved weight distribution.) The previous Tour 90s I'm guessing had most of the weight centralized near the top of the handle (right under or at where the Wilson W logo is, which could account for why the design had a longer pallet design than the PS85 and the K90). The K90 was reworked to move that weight more towards 3&9 (if not slightly higher) and maybe moving whatever's left of the mass closer to the buttcap. This explains the higher swingweight.

What really matters in making a racket the best that it can be is WEIGHT DISTRIBUTION. That and that alone is what makes a great racket what it is. Well... That and mass... But mass is useless if it's just slapped on randomly.

If you have any questions, feel free to ask them. Try to be as specific as possible, and I'll try to cut it down and be more concise next time I respond. >< src="http://tt.tennis-warehouse.com/images/smilies/icon_smile.gif" alt="" title="Smile" class="inlineimg" border="0"> But as you can guess, there's a lot more behind rackets and their performance than just their specs (unless we got far more detailed about the specs of the rackets).

Oh, and I took this out of the previous post (too long) cause it wasn't wholly relevant, but I still think it's rather interesting information (though I have no solid proof since I don't have a bunch of advanced equipment as well as Sampras' rackets and so on). It is purely theoretical (most of it), but I feel it's quite logical and it explains a lot of what is already confirmed and what I read on these boards (which isn't always true as we know when it comes to conspiracy theories of pro rackets).

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The ProStaff Tour, which the n90 design is based off of, was meant for Pete Sampras. Sampras would place a lot weight around that general area where a majority of the ProStaff Tour's weight is centered as counterbalance for the lead he puts on the head (or at least Nate Ferguson did it). With this, Ferguson would have to put less lead in his racket and could just slap it on the head and be done with it. (Yes, Wilson will occasionally make rackets specifically designed for top pros and sell them to the public, which is a mistake since those rackets were incomplete and require lead to finish it.) This is another reason why the K90 is so popular - it's a finished product. Federer has been using that EXACT racket (specs, weight distribution, EVERYTHING) for 7 years now. Recently he seems to be adding a little bit more weight to it, but it's hardly a noticeable difference aside from more comfort (it could explain the recent pile up of errors though in the past few years; yes I said it wasn't a noticeable difference, but some people can feel the performance difference and I'm sure Federer is one of them). He probably did it in his attempt to create a heavier ball and win the French Open. Everything he's done in the past several years has all been for that. If he never cared, he'd still be ripping relatively flat, penetrating winners all over the place. Now he hits with far more spin and might have changed his racket setup slightly since 2006 to help that. All I really know though, is since his switch to the K90 (or him staying with the K90 but with the K90 paintjob, whatever you prefer), is that his groundstrokes are occasionally very erratic, which has pretty much never happened during his rise to power and his stay atop the ATP ladder. Also, sometime since the switch, he's been adding weight under the bumper guard (polarizing the racket, making it less stable as I mentioned). You put two and two together and you can logically infer these points that I have mentioned. If he stayed with a stock K90 (with tight quality control), he probably would still be playing as well as he did in 2006 (and still won the French Open without sacrificing the 2008 Australian Open, 2008 Wimbledon, and the recent 2009 US Open). But either way, he'd still get crushed by Nadal. Polarizing your racket only makes it worse against him. But at least he generates a heavier ball and still dominates a majority of the tour.

For adding the 15 grams, you can go either way with that actually. 9 grams at the head or handle, it doesn't really matter. 9 at the head will produce more power, while 9 at the handle will be more manageable.

And you're right about the difference between depolarized and polarized, except that polarized doesn't necessarily straight out give more power. It gives more racket head acceleration. That can essentially equate to more power as power/force is generated from either (or both) increases in mass or velocity/acceleration. I'd prefer to keep it at polarized means more racket head speed (if you know how to use it right). Also, the control problem isn't as big of a factor as I might make it sound. Higher racket head speeds (especially at the tip) can be used to create more spin on the ball, resulting in more control. Your ability to accurately control the racket head at high speeds will surely go down, but as long as you use spin to give you margin it's going to be fine (but don't be too surprised if a few don't go your way, but with the spin it generates you'll get plenty of margin so you won't notice 99% of the times where it happens).

And 10&2 and 11&1 will give still give power/plow through and increased racket head speeds, though I prefer to stick to one side and go all out in that direction. But if you were going to do that, I suggest 10&2 since it doesn't reduce your racket head control as badly but will give you noticeable more momentum in the head. If you go to 11&1 you might as well put a strip of lead across the top of the hoop. I don't personally advocate a bunch of 3-5 inch strips at 12 to polarize a racket, I prefer a long strip that can actually be as long as 15 inches across the top of the hoop so the center of mass won't be raised as much and the racket won't become more difficult to control. Some people prefer it that way, and I'm not saying you shouldn't do it. Try it, it might work for you, but it doesn't work for me.

It all depends on what you need from adding weight. Sometimes it's not as straightforward as wanting more power. You might want more pop, but are want a hint more spin on your shots than a 3&9 setup will give, and are willing to sacrifice a little pop to get there. In that case, yes go for 10&2.

If you want more pop on your serves, I recommend lead at 3&9 unless you might want to get a little added spin and kick on you spin serves as well, then 10&2 might be more appropriate. I've never personally experimented with 10&2 but it should add more spin than a 3&9 setup although you will probably lose a little stability and power (probably not a noticeable loss though unless you add a lot of weight). Personally, a polarized setup messed with my serve the most. Granted the amount of spin and kick I got on slice and kick serves was truly amazing, but it was difficult to really control it and stay as consistent as I liked with it. Occasionally I'd get too much lift and send it long, or too much spin and send it short or into the net (but with a giant explosion off the court). Granted, I didn't stick with the racket and practice with it as much as I should have, which probably would've fixed the problem, but from an immediate racket switch standpoint, it was simply too erratic. Now, for groundstrokes, I don't think I missed a single topspin stroke long or into the net. I easily ripped the ball 2-4 feet over the net and had them all safely drop on or inside the baseline with no problem and had insane amounts of kick on them. My friend could actually consistently pull off drop shots with so much spin they landed next to the net and died on the bounce, if not going back into the net. And he ran me around all over the court using heavy spin to generate sharp angles to both sides of the court. Depolarized setups are great for people that love to use heavy spin or those who look to add more spin to their games (and want to play with heavy spin). Playing flat with this racket is meaningless (and maybe risky as well, though I wouldn't know). So for serves, you'd really have to put some more spin on them to control them. You can still hit everything very quickly through the court, but you need to use more spin to control it and gain back the accuracy you lose. In the end though, you can hit just as hard, if not harder than before, but with much more spin and safety. You just won't get nearly as much pace as a depolarized racket. I mean, you can still hit flat groundstrokes and flat serves with plenty of pace, but it's not where the racket really shines for me. If you're going to specialize in that, might as well depolarize your racket.

When using a depolarized setup on serves, I could still generate plenty of spin (same if not more than usual) to drop second serves consistently into the court deep with the same amount (sometimes more) of action and kick. The only difference was that those second serves were moving through the court at least 10 mph faster. My friend tried serving to me with one of my depolarized rackets and me using the polarized racket, and I couldn't even push the ball a foot in front of me. The ball was just so heavy, AND it came in faster than normal. A big server playing with a depolarized racket doesn't really have to worry much about holding serve. They just bomb a big first serve, then finish off whatever floater comes back. It's part of the reason Sampras had such an easy time on serve. Maybe 20% of the reason. His racket was heavier than most, and as such (with the spin and pace he generated) people had a difficulty keeping their racket stable and plowing through the ball at contact. Playing with a depolarized racket, most first serves were service winners and most second serves were essentially slightly slower first serves with more kick (compared to me using my regular racket).

Actually though, if you made contact around where 10&2 is, you'd get more plow through than with a 3&9 setup. Most people generally make contact at 3&9 though. Nate said pros generally hit higher up on the stringbed (hence the placement of Federer's string savers), but I doubt that. Pictures and slow motion videos at contact show that the pros still hit almost exactly in the center aside from a few shots where they'll hit it closer to the top (intentionally or accidentally I'm not sure).

And generally I read a lot, paid attention in physics when we learned about force, conservation of momentum, and so on (stuff that can be applied to rackets), and I actually experiment a lot with racket customization. I have 2 heavily depolarized rackets at 13.8 ounces that generate tremendous amounts of power, 1 polarized racket at 12.5 ounces (without overgrip) that generates tremendous amounts of spin, 1 lightly depolarized racket at 12.9 ounces that has a lot of power and slightly increased spin, and 3 slightly depolarized K90s (that I'm testing out to decide if I'll switch to this setup or not; 2.5 grams under the bumper) that are more comfortable during swinging and generate a little more racket head speed and spin/lift. My dad also uses a heavily depolarized racket (that he personally made through months of trial and error to slowly add and remove weight until he found the perfect setup) weighing in at around 13.3 ounces.

And one final word, if you polarize a racket, the more weight you add, the less you'll notice the inconsistencies of the racket, but you can easily fix that with practice time.

Oh, and the bit about adding weight 7 inches above the buttcap came from a John Cathen I believe. It wasn't my idea. I tried it out and it worked beautifully (solved the problems I had with depolarizing a K90 because originally I was reluctant to put weight under the grip fearing bulkiness under the leather, which wasn't even noticeable). Here's a step by step of how to depolarize your racket.

http://tt.tennis-warehouse.com/showp...64&postcount=1

His ideas differ slightly from mine, but he's probably got more experience in the subject. Then again, that might be why he's seen as such a crazy person to some people. That, or his nonstop ranting about concepts people don't understand because he doesn't explain them or their benefits too well. But he has a pretty solid grasp of what he's doing as well... Though he seems to change his racket setups far more than most people, and he goes nuts when a pro (like Federer) doesn't full on fit 100% into his beliefs of racket setups. When he found out Federer's racket wasn't as heavily polarized as he thought it was, he freaked out and went on a rampage.