Physics 101. Rough strings can't give you more spin.

[TimeToPlaySets]

The racket brushes upwards.
The ball's rotation stops and reverses.
Spin is created when the ball rotates at the same rate as the racket head.
After that, they are spinning the same speed.
Rough strings simply reverse the balls spin sooner, but can not increase the rate of spin.
The ball simply can never spin FASTER than the object imparting the spin in the first place.

But, don't take it from me, take it from
Howard Brody is an emeritus professor of physics at the University of Pennsylvania
Rod Cross is an associate professor in physics at the University of Sydney, Australia

https://www.amazon.com/Technical-Tennis-Racquets-Strings-Courts/dp/0972275932

 

[rogerroger917]

You just shut down the entire strings industry.

 

[steve260z]

Non sense

 

[1HBHfanatic]

I subscrive to "the tennis lore", group of ppl who use string and pattern changes to move the ball differently,,

Sorry OP, not buying these findings;
I believe in what my own strokes tell me when hitting the ball.

 

[1HBHfanatic]

Here is a quick conperason, for all whove tried these 2 strings on the courts..

head.gravity strings vs head.sonic.pro strings
same rakets, same tension

which is gonna kick.serve higher, spin the ball more and fuzz up the ball quicker?

 

[mpournaras]

Here is a quick conperason, for all whove tried these 2 strings on the courts..

head.gravity strings vs head.sonic.pro strings
same rakets, same tension

which is gonna kick.serve higher, spin the ball more and fuzz up the ball quicker?

Thats shaped not rough

 

[Irvin]

@TimeToPlaySets since you’re talking about elementary physics let’s talk about the basics of physics. An object at rest stays at rest and an object in motion stays in motion. The lower the friction between the ball and the string bed the less spin is produced. The greater the friction the more spin you will have. Never will you immediately get the ball spinning at the same speed tas the racket is traveling.

If you play golf put Vaseline on the club face and see if there is any way you can slice or hook the ball. Impossible! You may be able to get a 1 foot fade or draw out of a 250 yd drive but it is impossible to hook or slice the ball.

EDIT: What you’re saying means you can start and stop just as fast on snow and ice as you can on dry pavement.

 

[El_Yotamo]

Yup, Irvin is right. It's all about friction. This is especially noticeable in cases where the inter-string friction is lower, as this allows the string to deflect and snap back better. Hence double-copoly hybrids are a very good way of increasing spin potential.

 

[Irvin]

I'm not sure I believe that snap back produces more spin than with any other strings. For instance, I think I can get more spin out of a Kevlar / SG hybrid than I will get out of a Poly full bed set up and I doubt the Kevlar / SG will have the snap back capability of any poly string. But if a string is going to snap back first it has to give or bend as it comes in contact with the ball. In order for that string to bend it must have a good ball to string bed friction and the longer that ball and string bed stay in contact with each other the more spin you are going to get. Snap back may produce more spin but I am not convinced of that yet. First and foremost I rely on actual play to determine if a setup produces more spin or not.

 

[skydog]

I think the key statement in the text is: “achieving a higher friction force over a smaller time and others by a lower force over a longer time.”

If the impact time is relatively similar, would it not stand to reason that the higher friction force will create more spin if the impact time is not long enough for either the higher friction force or lower friction force to achieve its 100% potential spin?

 

[Dartagnan64]

They seem to ignore snap back entirely in that snippet. If the strings grab the ball and then snap back that will impart spin separate and additive to the spin imparted by technique.

Maybe because its an older book before the polyester string revolution. I notice they don't mention poly strings in their "tennis lore". They talk about gut and polyurethane coatings which increase ball-string friction but not about reducing inter-string friction through poly.

So textured or shaped poly is probably a foreign concept to them where you have a string with both high string-ball friction and low string-string friction.

 

[rogerroger917]

Why is ttps quoting old research then? Maybe find some research saying wood rackets serve faster than boat oars so we need to ditch our babolats and play with a maxply. Lame.

 

[Moveforwardalways]

String up Big Hitter Black Seven and Wilson NXT in two identical racquets and hit with a partner. Then ask them which ball had more spin.

 

[Irvin]

They seem to ignore snap back entirely in that snippet. If the strings grab the ball and then snap back that will impart spin separate and additive to the spin imparted by technique.

Show me a video where the strings snap back before the ball leaves the string bed. If the strings snap back after the ball leaves the string bed it does not do anything for spin.

String up Big Hitter Black Seven and Wilson NXT in two identical racquets and hit with a partner. Then ask them which ball had more spin.

There you go. If your opponent (or you) think the spin is better that is the ultimate test of any combination.

 

[TimeToPlaySets]

. The idea is that the ball with eventually have the same speed as the string. How quickly it gets there doesn't matter. Rough simply grabs sooner.

After that, the ball spins in the direction of the sound.. guess what? Same Max speed. Simple.

Book was written in 2005 and is aware of poly. I suspect poly spin generation is greatly overstated.

Bottom line,. What spins the ball? The speed of the strings. Basic stuff

 

[BlueB]

What spins the ball? The speed of the strings. Basic stuff

Speed of the strings has 2 outcomes, resulting from the difference of the angle of incoming ball and racquet head path, and the difference of angle of the stringbed to the direction of outgoing ball:
1) Lineal speed of the ball to the desired direction;
2) Rotation of the ball or "spin".
People here like to talk about "plow" or "hit trough" and "brush up" stroke, which are really the components of the same stroke...
Ball has limited time of contact with the string bed, before the "plow" sends it away. If there is slippage in the "brush up" component, the maximum spin will not be achieved.

Or, you can turn the focus away from the strings for a second and just think what happens with the outgoing trajectory of a flat struck ball, after it hits various court surfaces:
On clay or gritty hard court, it's going to kick up and some of the speed will be transformed into spin (even if the incoming ball was completely flat);
On grass, sleek hardcourt or Astroturf that wasn't sanded much, the ball will bounce lower, maintain more of the lineal speed, sometimes would even appear to skid a bit.
Everyone that played on multiple surfaces knows this.

 

[FiReFTW]

@El_Yotamo told me that shaped poly main and smooth poly cross is best for spin, and I trust him since he has made alot of experiments with this, and I notice I also get more spin.

 

[Dartagnan64]

.

Book was written in 2005 and is aware of poly. I suspect poly spin generation is greatly overstated.

Tell that to every serve and volleyer in the early 2000's. They called it the Luxilon dip for a reason.

And it's quite possible the research was done well before the book was published and before the polyester revolution.

 

[Dartagnan64]

Show me a video where the strings snap back before the ball leaves the string bed. If the strings snap back after the ball leaves the string bed it does not do anything for spin.

http://twu.tennis-warehouse.com/learning_center/stringmovementPart2.php

The above TWU link discusses string deflection and snap back and how it relates to spin. Videos aren't too great but the inference is clear that setups with the greatest string deflection produce higher spin. Only way that happens is if the strings are snapping back before the ball leaves the strings.

This is there conclusion:
"The videos (here and at the links above) show that string movement does indeed occur at the angles and speeds tested. It is also shown that the strings do snap back for all setups and they do so, for the most part, in less than 1/1000 second. We can't see the details of what occurs during that 1/1000 second between video frames, but the evidence makes it reasonable to assume that the strings are indeed spinning the ball. "

Given how fast snapback happens I doubt I'm going to find a good video. Doesn't mean it doesn't happen.

 

[Irvin]

Videos aren't too great but the inference is clear that setups with the greatest string deflection produce higher spin. Only way that happens is if the strings are snapping back before the ball leaves the strings.

I've read all that 'stuff' but I don't believe everything I see on the internet for the most part no matter who puts it out. The greater the string deflection the greater the string to ball friction and the greater the friction the less the ball slides or slips over the string and the greater the spin. Let's just agree to disagree for the time being.

 

[am1899]

I suspect poly spin generation is greatly overstated.

Some Brazilian guy (that a lot of people never heard of) shows up at the French Open with new string, and wins the whole tournament. I wonder if Guga’s opponents in that French Open thought poly spin generation is greatly overstated? And unless you’ve been living under a rock since the late 90’s, early 2000’s, you saw what happened - most anybody who was anybody on the pro tour, eventually switched to some kind of poly or poly hybrid. Why? During the same time, serve and volley tennis just about disappeared from the game all together. But none of that has anything to do with poly or spin, right?

 

[Booger]

Science aside, I can't say that I've noticed much, if any, difference in spin when using a rough string. Maybe a tiny bit, but maybe it was placebo.

Compare that to a shaped string where the ball has a completely different flight path and strokes need to be adjusted to compensate.

 

[TimeToPlaySets]

Don't tell me, tell it to the PhD Physicists who are proving your placebo snake oil strings wrong.

 

[Big Bagel]

The idea behind textured/shaped strings is to increase ball-string friction. If you watch videos of balls hitting off racquets, you will generally see the strings deflecting, the ball will actually slide over a few strings, and then the strings snap back, pushing the ball out with spin. There's two frictions at play here: string-string friction and ball-string friction. For maximum spin, you need to minimize string-string friction allowing for maximum string displacement and quickest snapback. You also need to maximize ball-string friction to prevent the ball from from sliding across the strings. Textured/shaped strings increase ball-string friction but also increase string-string friction. The makers of MSV strings actually helped fund a spin-oriented study and found that for their Focus string, their Co-Focus (round) string produced more spin than their Focus-Hex (6-sided) string when they were the same gauge and the same material and manufacturing process other than the extruded shape at the very end of the process. Other strings, such as the Luxilon rough strings, have been shown to increase spin over their round counterparts.

Overall, the issue of spin is tricky, but in general, it is accepted form studies that shaped/textured strings do add spin. The MSV study is supposedly an outlier, although I'd love to see a lot more studies on this. And if you doubt the legitimacy of snap-back, take a look at Spaghetti Strings or Gamma Glide string, along with accompanying videos/studies.

 

[TimeToPlaySets]

The makers of MSV strings actually helped fund a ... study and found that .

Statistics 101.

 

[TimeToPlaySets]

Again, use your common sense.
It is physically impossible for a rough string to add spin.

Do you think the ball would spin faster if he wore a gardening glove?

 

[fundrazer]

Why does any of this even matter? If somebody plays better with a texture/shaped poly compared to rounder poly, good for them. Same thing applies to racquet companies. The marketing gimmicks are often misleading, but if the stick is good then I don't see much of a point to complain about it.

But I guess I didn't spend thousands of dollars on tennis lessons figuring this out so what do I know.

 

[BlueB]

Again, use your common sense.
It is physically impossible for a rough string to add spin.

Yes, please do use common sense.
Is it also impossible for a tire with good thread to have more grip on a slippery road, then a worn out one?
Or, what can you tell us about different ball bounce and rebound spin on different court surfaces?
Or, why a new pingpong racquet with "sticky" rubbers spins the ball better then an old dusty one?

 

[dak95_00]

Next you’re going to find a doctor who says immunization causes birth defects....

(Wait. That’s another thread.)

 

[am1899]

Don't tell me, tell it to the PhD Physicists who are proving your placebo snake oil strings wrong.

The only thing proven is that some people are foolish or naive enough to believe outdated and potentially dubious scientific conclusions, in the face of mountains of contradictory evidence.

 

[BRS1076]

Thoroughly confused. The physicist's explanation does make a lot of sense to me, but I do feel like that I generated more spin with Luxilon compared to any synthetic gut. I agree with the physicist that there are other factors that affect spin more than the friction associated with a rough textured string (i.e. the path of the racquet). But is the phyiscist saying that there are no changes that can be made to stringbed to generate more or less spin?

For me trying to hit a flat forehand like Llendl or Federer with ALU Power was just underpowered and quite frankly uncomfortable. ALU Power felt much more comfortable the more I fanned the fan like Rafa or Jack Sock. The more I fan, the more topspin I generated, and I felt like I had a greater margin for error when increasing my swingspeed. In this instance, I am altering my mechanics to impart more spin.

However, this anecdotal evidence (not scientifically verified mind you) would still suggest that there is some factor at play or else I would not need to alter my swing in the first place.

Conceptually, I accept that friction is not a repulsive "push" force that it is only a "drag" force that brings the ball to a stop on the stringbed. It seems counter-intuitive to suggest that friction does not reverse the spin of the ball 180°. The ball is spinning towards you as you make contact. The physicist asserts that the drag created by friction halts the rotation, but once the rotation stops, the scientific evidence suggests that the friction does not cause the ball to rotate in the opposite direction. It is the swingspeed and the path of the racquet that imparts the spin at this point. The scientific data is that friction does not measurably impart more spin than what the racquet is already giving the ball.

If I were to pin a tennis ball against the net accord with my racquet, the assertion is that the ball will have the same amount of RPMs when I brush the ball over the net no matter what string I use. I can accept this.

However, I still feel the need to augment by mechanics to keep the ball sailing with ALU. This would suggest to me that there is some other "factor" at work. Can the stiffness or elasticity of a stringbed augment the dwell time on the stringbed or change the point when the ball leaves the stringbed?

Otherwise, the absence of such a factor would prove the existence of a placebo effect illustrating that all of us tennis players are just nuts. Meh... that seems just as plausible.

 

[Dartagnan64]

I've read all that 'stuff' but I don't believe everything I see on the internet for the most part no matter who puts it out. The greater the string deflection the greater the string to ball friction and the greater the friction the less the ball slides or slips over the string and the greater the spin. Let's just agree to disagree for the time being.

Except the physicists in the OPs article say ball friction doesn’t increase spin. So now you are saying both physicists and the TWU testers are wrong. That’s a whole lot of empiric evidence you are tossing out for what are probably dubious reasons.

The “I can’t see it so it can’t be happening” argument is so pre-enlightenment.

 

[El_Yotamo]

Thoroughly confused. The physicist's explanation does make a lot of sense to me, but I do feel like that I generated more spin with Luxilon compared to any synthetic gut. I agree with the physicist that there are other factors that affect spin more than the friction associated with a rough textured string (i.e. the path of the racquet). But is the phyiscist saying that there are no changes that can be made to stringbed to generate more or less spin?

For me trying to hit a flat forehand like Llendl or Federer with ALU Power was just underpowered and quite frankly uncomfortable. ALU Power felt much more comfortable the more I fanned the fan like Rafa or Jack Sock. The more I fan, the more topspin I generated, and I felt like I had a greater margin for error when increasing my swingspeed. In this instance, I am altering my mechanics to impart more spin.

However, this anecdotal evidence (not scientifically verified mind you) would still suggest that there is some factor at play or else I would not need to alter my swing in the first place.

Conceptually, I accept that friction is not a repulsive "push" force that it is only a "drag" force that brings the ball to a stop on the stringbed. It seems counter-intuitive to suggest that friction does not reverse the spin of the ball 180°. The ball is spinning towards you as you make contact. The physicist asserts that the drag created by friction halts the rotation, but once the rotation stops, the scientific evidence suggests that the friction does not cause the ball to rotate in the opposite direction. It is the swingspeed and the path of the racquet that imparts the spin at this point. The scientific data is that friction does not measurably impart more spin than what the racquet is already giving the ball.

If I were to pin a tennis ball against the net accord with my racquet, the assertion is that the ball will have the same amount of RPMs when I brush the ball over the net no matter what string I use. I can accept this.

However, I still feel the need to augment by mechanics to keep the ball sailing with ALU. This would suggest to me that there is some other "factor" at work. Can the stiffness or elasticity of a stringbed augment the dwell time on the stringbed or change the point when the ball leaves the stringbed?

Otherwise, the absence of such a factor would prove the existence of a placebo effect illustrating that all of us tennis players are just nuts. Meh... that seems just as plausible.

The physicists he's quoting are outdated. In fact, Rod Cross and Crawford Lindsay have gone back and refuted what that article says.

 

[Irvin]

Except the physicists in the OPs article say ball friction doesn’t increase spin. So now you are saying both physicists and the TWU testers are wrong. That’s a whole lot of empiric evidence you are tossing out for what are probably dubious reasons.

The “I can’t see it so it can’t be happening” argument is so pre-enlightenment.

The physicists he's quoting are outdated. In fact, Rod Cross and Crawford Lindsay have gone back and refuted what that article says.

True but I more agree with their original position.

 

[sredna42]

Good thread, this is a subject that does my head in.

I use gut/poly, and get decent spin, though it definitely rewards technique, and I never feel like I am getting "free" spin.

I tried a full bed of red code wax in one racquet, the idea being there would be minimal friction between the strings allowing for maximum snapback.
In practice though, it felt as though the ball just smeared off the stringbed, and I played terribly with it. Though my coach who is very high level loves red code wax in a full bed and gets plenty of spin. ??????? probably because my technique is garbage.

I got the same feeling when I had the genius idea to spray silicon spray on one of my frames with gut/poly. Instead of facilitating snapback, the ball felt like it was just slipping or smearing off the stringbed it was awful.

I wish we could get mythbusters to do a segment on it. Adam and Jamie would rig up some racquet machine that swung the racquet precisely the same everytime to hit a ball fired precisely the same angle and speed every time, then measured the spin, the only variable then being the strings.

 

[Big Bagel]

Poly strings clearly give you more potential because they snap back quicker and more completely (you don't have to straighten them) than synthetic gut. Even this physicist should agree with that, because while the racquet head speed might be the same, if the strings snap back at different speeds, then whichever snaps back quickest will generate the most spin. Poly snaps back quicker, ergo poly generates more spin.

The textured string doesn't just grab the ball quicker, it prevents it from sliding across the strings. Like it was already mentioned, the different court surfaces clearly affect ball spin, so string surface would as well. Clay has more material to grab the ball more and prevent the ball sliding on the court, so it accentuates spin more than grass. Shaped/textured strings have the same effect. Just watch how high the ball is bouncing at the French Open compared to Wimbledon and you will see the difference.

As a side note, if you are not convinced that snap back creates spin (which you should be if you look at spaghetti string or Gamma Glide), you should be even more convinced that textured strings affect spin due to the same argument. It's more complicated with snapback because the texture actually creates more string-string friction which hinders snapback, but it increases ball-string friction which increases spin regardless of snapback.

 

[Kevo]

I tried a full bed of red code wax in one racquet, the idea being there would be minimal friction between the strings allowing for maximum snapback.
In practice though, it felt as though the ball just smeared off the stringbed, and I played terribly with it. Though my coach who is very high level loves red code wax in a full bed and gets plenty of spin. ??????? probably because my technique is garbage.

There are a lot of factors in spin production. A change in any one factor can increase or decrease spin. One thing that people don't seem to consider in these threads very much is the deformation of the ball. If you have slick strings the ball can slide on those strings to some degree, but if you hit hard the ball will flatten on the strings and sink into them. That will negate the slide. It also adds some rotational energy into the ball deformation.

For me, technique is by far the most important part of spin. Strings help, but the difference between strings is somewhat non-deterministic between players. There is the interplay between the strings, the tension, and the feel. You might find a string that seems to enhance your spin, but it might also launch the ball more than you like, so you increase the tension and now you don't like the feel any more. It's a very personal problem for every player to find what they like.

 

[Demented]

This is actually a very easy argument to dispel. They are 100% correct that if the racket face is relatively perpendicular(flat) to the ball path then string friction doesn't matter an iota. Where string friction comes into play is when you hit the ball while 'covering' or rotating the racket face over the top of ball. As your racket face angle deviates below 45 degrees to the ball path, the ball doesn't have enough friction to remain on the strings without sliding down the face. This can be easily reproduced by trying to slice the ball with the racket face at like a 20 or 25 degree angle, the ball won't grip. This leads to more spin because you can elongate the dwell time of the ball by covering it, allowing for you to achieve maximum upwards velocity.

 

[El_Yotamo]

True but I more agree with their original position.

There's a really nice quote by Neil DeGrasse Tyson: "The good thing about science is that it's true whether or not you believe in it".

Let's agree to disagree

 

[ByeByePoly]

There are a lot of factors in spin production. A change in any one factor can increase or decrease spin. One thing that people don't seem to consider in these threads very much is the deformation of the ball. If you have slick strings the ball can slide on those strings to some degree, but if you hit hard the ball will flatten on the strings and sink into them. That will negate the slide. It also adds some rotational energy into the ball deformation.

For me, technique is by far the most important part of spin. Strings help, but the difference between strings is somewhat non-deterministic between players. There is the interplay between the strings, the tension, and the feel. You might find a string that seems to enhance your spin, but it might also launch the ball more than you like, so you increase the tension and now you don't like the feel any more. It's a very personal problem for every player to find what they like.

"For me, technique is by far the most important part of spin."

You have to have the technique to hit low to high, so there's that.

A heavy hitter (someone that compresses the ball on those low to high swings) can hit big topspin with any string. The question here is if the ability to hit that heavy ball is "technique" , or maybe something else ... "strength"?

I can speak for those that don't it that very heavy ball (most of us rec players). I can hit big (not heavy) topspin with fb rpm blast 16 ... I can hit pretty big dip on a topspin lob for example. With the same low to high stroke (technique) , I get very little topspin with fb origin. I look at my spin with fb rpm, and lack of spin with fb origin, and can't come to the conclusion for my swing "it's mainly technique". Actually, no ... for my swing it was mainly rpm.

Throw this in the mix. The heaviest ball I ever faced was someone hitting Forten Sweet 15g. I hit with his 12+ oz racquet, and even with an exaggerated low to high I could only get moderate spin. I didn't have the swing speed to compress the ball good enough to create the big spin. The missing piece of the puzzle for me would have been seeing that guy hit fb rpm. If you include hitting heavy (compressing the ball) as technique, and if this player only got a marginal bump in ts with rpm ... then "it's mainly technique" would be accurate for this player.

Most rec players will never hit heavy enough to the point strings would not matter ... imo. I would have no idea what percentage of Nadal's spin is his swing and strength vs how much is string. My guess is strings matter a lot even with Nadal.

 

[Irvin]

There's a really nice quote by Neil DeGrasse Tyson: "The good thing about science is that it's true whether or not you believe in it".

Let's agree to disagree

Well were Cross and Brody wrong when they said rough strings do not produce more spin or when they said they do?

 

[Kevo]

"For me, technique is by far the most important part of spin."

You have to have the technique to hit low to high, so there's that.

A heavy hitter (someone that compresses the ball on those low to high swings) can hit big topspin with any string. The question here is if the ability to hit that heavy ball is "technique" , or maybe something else ... "strength"?

Depends on what you mean by strength. Most power comes from the legs and trunk. I've seen 12 year old girls hit big, so I think it's not as much about strength as it is technique.

I can speak for those that don't it that very heavy ball (most of us rec players). I can hit big (not heavy) topspin with fb rpm blast 16 ... I can hit pretty big dip on a topspin lob for example. With the same low to high stroke (technique) , I get very little topspin with fb origin. I look at my spin with fb rpm, and lack of spin with fb origin, and can't come to the conclusion for my swing "it's mainly technique". Actually, no ... for my swing it was mainly rpm.

Well, I think your experience meshes with what I was saying earlier. There's going to be differences between players. Presumably at some tension you would be able to get decent spin out of fb origin. Swing speed can overcome tension for spin. With poly the string is stiff already so you don't have to swing as hard to make the ball flatten on the strings. If you do swing hard though, the effect is enhanced. Kevlar works really well for spin too, but it's so stiff it can be even worse than some polys on the joints.

Throw this in the mix. The heaviest ball I ever faced was someone hitting Forten Sweet 15g. I hit with his 12+ oz racquet, and even with an exaggerated low to high I could only get moderate spin. I didn't have the swing speed to compress the ball good enough to create the big spin. The missing piece of the puzzle for me would have been seeing that guy hit fb rpm. If you include hitting heavy (compressing the ball) as technique, and if this player only got a marginal bump in ts with rpm ... then "it's mainly technique" would be accurate for this player.

I would suspect that they would get a little more spin, but maybe not a huge bump. IIRC, Sweet does have a little texture to it, but isn't a super soft nylon, so I would imagine a little more slide in the strings on the rpm would help some, but I don't think it would be a whole other level.

Most rec players will never hit heavy enough to the point strings would not matter ... imo. I would have no idea what percentage of Nadal's spin is his swing and strength vs how much is string. My guess is strings matter a lot even with Nadal.

Nadal would hit big spin with a $20 frame off the shelf of Wal-Mart.

I agree that for most rec players it won't make much difference. That's why I usually recommend people find a string that they like the feel of hitting with and just adjust tension as needed. I think being connected to the feel of contact and enjoying it is the most important part of picking a string for most people. Then once you get to the point where you're breaking it all the time you have to probably make some compromises, but at least starting out it's about the feel IMO.

 

[BlueB]

Well we’re Cross and Brody ...

We are not Cross and Brody, they are

Sent from my SM-G930W8 using Tapatalk

 

[fuzz nation]

String up Big Hitter Black Seven and Wilson NXT in two identical racquets and hit with a partner. Then ask them which ball had more spin.

Sure, we'd expect to "get more spin" from the racquet strung with BHB7, but I think it's worth noting that sometimes what we're probably seeing there is "spin effect" - that means that the ratio of velocity to spin with the shots from the BHB7 racquet make the ball turn or curve more than with the NXT.

But the NXT might be generating just as many raw rpm's on the ball. It's hard to tell though, because NXT is also lively stuff - it readily generates a good deal of velocity on the ball compared with poly. So if I produce just as many rpm's on the ball with the NXT frame, but I also hit the ball with let's say 15% more velocity, the spin simply can't turn that ball as much as a slower shot. The BHB7 racquet may produce a slower shot (from the same swing speed).

I only offer this because I'm not so over the moon on poly. Whenever I've tried it, one of the things I notice almost immediately is that my racquet strung with poly or a poly hybrid has less "pop". The poly plays a little more dead. So if my regular stroke with the same angular contact is making the same spin and my shots are slower, of course the "spin effect" will be more dramatic.

Don't get me wrong, gang. I'm no math heavy and I can't say definitively what's going on with all these gear interactions, but sometimes it seems that the relative "deadness" of poly gets ignored in some of these discussions. Yes, it can also probably slide and help grab the ball rather well, but I don't think poly - smooth, shaped, or rough - is as miraculous as we sometimes make it out to be around here. Just my take...

 

[Stretchy Man]

But, don't take it from me, take it from
Howard Brody is an emeritus professor of physics at the University of Pennsylvania

"All strings achieve about the same results with respect to spin."

Your emeritus professor clearly doesn't know what he is talking about.

 

[sredna42]

There are a lot of factors in spin production. A change in any one factor can increase or decrease spin. One thing that people don't seem to consider in these threads very much is the deformation of the ball. If you have slick strings the ball can slide on those strings to some degree, but if you hit hard the ball will flatten on the strings and sink into them. That will negate the slide. It also adds some rotational energy into the ball deformation.

For me, technique is by far the most important part of spin. Strings help, but the difference between strings is somewhat non-deterministic between players. There is the interplay between the strings, the tension, and the feel. You might find a string that seems to enhance your spin, but it might also launch the ball more than you like, so you increase the tension and now you don't like the feel any more. It's a very personal problem for every player to find what they like.

You are right, I know it deep down I think the truth that I am running from is simply that my technique, especially my forehand, is so awful that I am in denial and my coach is too polite to tell me. So I constantly convince myself the problem is the racquet, or the strings.

Solinco Hyper-G was the latest purchase that was going to "revolutionize" my forehand LOL

TW must love me

 

[ByeByePoly]

Depends on what you mean by strength. Most power comes from the legs and trunk. I've seen 12 year old girls hit big, so I think it's not as much about strength as it is technique.



Well, I think your experience meshes with what I was saying earlier. There's going to be differences between players. Presumably at some tension you would be able to get decent spin out of fb origin. Swing speed can overcome tension for spin. With poly the string is stiff already so you don't have to swing as hard to make the ball flatten on the strings. If you do swing hard though, the effect is enhanced. Kevlar works really well for spin too, but it's so stiff it can be even worse than some polys on the joints.




I would suspect that they would get a little more spin, but maybe not a huge bump. IIRC, Sweet does have a little texture to it, but isn't a super soft nylon, so I would imagine a little more slide in the strings on the rpm would help some, but I don't think it would be a whole other level.



Nadal would hit big spin with a $20 frame off the shelf of Wal-Mart.

I agree that for most rec players it won't make much difference. That's why I usually recommend people find a string that they like the feel of hitting with and just adjust tension as needed. I think being connected to the feel of contact and enjoying it is the most important part of picking a string for most people. Then once you get to the point where you're breaking it all the time you have to probably make some compromises, but at least starting out it's about the feel IMO.

"I agree that for most rec players it won't make much difference."

I think you missed my "not" in my sentence. My belief is most rec players will never hit a very heavy ball, and for those players strings like rpm would definitely add spin to any low to high swing.

I only played fb origin @55, so perhaps @65 I would have seen good spin. I doubt it though, based on Chris's comments in the TW review. He took it up to high 60s without spin. I get good spin with the origin/velocity 55/52 ( in my signature) ... so there is more than string stiffness involved (at least with my swing).

On strength vs technique with the heavy ball, I see strength (a lot of arm stregth). I haven't played 12 year old girls, but many ex-D1 guys. I have seen plenty of big pace, and big topspin ... but rarely see them together. Obviously I have never played WTA players, but from watching matches on TV, I don't see a lot of Nadal "heavy" in their strokes. Madison can knock the cover off (mph), but flattish. Technique and timing and rotational speed and legs can take you a long way, but it doesn't take you to Nadal. Nadal, Wawrinka, Thiem ... the strength component seems pretty obvious to me. Rotational forces can't account for the visous upper cut Nadal adds to his swing.

I guess someone will point out some skinny dude or junior girl hitting "Nadal heavy" and blow my theory up. I used to use Henin as an example of evidence it must all be technique. But going back and looking at video, that young lady looked very strong.

 

[Liam Grennon]

If you go to a play sight court with ALU power in one racket and ALU power rough in the other racket. If you then play for an hour save your results then another hour with the other racket, ALU Power Rough will give me more RPM. I know this because I have done it....

 

[TimeToPlaySets]

If you go to a play sight court with ALU power in one racket and ALU power rough in the other racket. If you then play for an hour save your results then another hour with the other racket, ALU Power Rough will give me more RPM. I know this because I have done it....

Placebo effect.
I will post more from the professor tomorrow

 

[fundrazer]

Placebo effect.
I will post more from the professor tomorrow

Nobody is asking you to.