So my unleaded BLX Pro Open, i thought was abit head heavy maybe 3-4 points so i stuck some coins in the butcap (roughly 8 grams maybe?). And now it seems to swing faster.
So my question is, do headlight racquets swing faster?
I thought changing balance did change swingweight.
I thought changing balance did change swingweight.
So my unleaded BLX Pro Open, i thought was abit head heavy maybe 3-4 points so i stuck some coins in the butcap (roughly 8 grams maybe?). And now it seems to swing faster.
So my question is, do headlight racquets swing faster?
Please see another thread as wellSo my unleaded BLX Pro Open, i thought was abit head heavy maybe 3-4 points so i stuck some coins in the butcap (roughly 8 grams maybe?). And now it seems to swing faster.
So my question is, do headlight racquets swing faster?
It does. The change in swingweight depends on where the balance point is but overall, shifting the balance will definitely change the swingweight.
If you would just imagine holding a baseball bat normally and swinging it by holding at the butt VS flipping the bat around and swinging it by holding at the tip, you would definitely notice a difference in swingweight. Since the balance point of a baseball bat is nearer to its tip than its butt, simply flipping the bat around changes its balance point based on your perspective.
If you can rotate faster it means more spin right?
This is a good question, one that I have pondered over many times. The OP should take a look at travlerajm's posts.
My own take is that at the hand, one feels two aspects of the racquet (not counting wind resistance). One is the static moment, and the other is the moment of inertia or swingweight.
There are also two main characteristics to a swing: the linear aspect, and the rotational aspect.
Totally linear swings are easy - the only thing that matters is the static weight of the racquet. It is much easier to move a racquet faster in a straight line if it is lighter. That said, most strokes are not purely linear...
Now assume you are applying a fixed torque at the handle, centered around the handle. The higher the static moment of the racquet, the slower it will rotate in a given time. Now "headheaviness" is a measure of the static moment, so in general, the more headlight a racquet is, the faster one can rotate it, given a fixed static weight.
Swingweight, for a fixed racquet length, is a measure of how the weight of the racquet is distributed. A high swingweight means there's more mass near the head of the racquet. The effects of swingweight come into play after you get the racquet moving, and it comes into contact with the ball - a high swingweight, meaning more mass at the head, will be good for plowing through the ball (crushing it).
So - if you have two racquets with the same mass and length, the one which is more headlight can be rotated faster, and the one which has more swingweight will have more plow through. To me, it seems that high moment is the enemy of all strokes. Even for linear strokes, high moment will cause discomfort. So for a given racquet weight, I would try to make it as headlight as possible (minimize moment) and maximize swingweight - a conflicting requirement, undoubtedly! - to the extent possible.
A very good post
http://tt.tennis-warehouse.com/showthread.php?t=408703&page=2 #22
provides a very good example ( C & D) for comparison.
Maybe you would care to comment about comparison of C & D
bhupaes...ABCD rackets comparisons don't make sense
bhupaes...ABCD rackets comparisons don't make sense
Serve is different than groundstrokesThanks, Julian, I had missed that post - I mostly only look at the Tips and Health/Fitness sections.
The comparison seems to be between two racquets with the following characteristics:
C) Weight: 12 ounces
Balance: Even
Swingweight: 330
D) Weight: 12 ounces
Balance: 9 points HL
Swingweight: 330
I would wager that racquet D will perform better in every way, and will be much more comfortable to play with. It will feel a lot whippier than racquet C, since one will be able to rotate it faster around the grip, and so will better for spin production. D will also be a lot more maneuverable than C, and so better at net. And having the same SW as C will make D at least equally effective in plowing through the ball.
To me, this makes D the preferable racquet for ground strokes as well as net play. I don't understand what corners means when he says that C will come around faster. It is possible that a person with long, linear strokes will like the feel of C better... humans are so gloriously unpredictable!
Serve is different than groundstrokes
Balanced rackets are better for serve
So I disagrree with your sentence "I would wager that racquet D will perform better in every way,"
A length of a lever should be as long as possible for serve.Just curious - is there a physical explanation for this? Or is it empirical knowledge? Thanks.
A length of a lever should be as long as possible for serve.
Shifting a location of a mass towards a handle helps the issue
1.Some players like Chang used 27.5 inch long racketYou mean shifting mass towards the racquet head, right? Sure, I buy that. You could make the racquet pretty head heavy, and if the player can handle it, he'll be able to hit even harder serves, I am sure - if that is his priority. But headlightness leads to greater maneuverability, which means the racquet will be much easier on the wrist, so one will get other benefits that are at least as important as brute force.
In the end, this is all qualitative analysis that falls into the realm of general guidelines. In practice, the absolute values matter IMO, and the physical attributes of the player - how strong his shoulders, arms, wrists are, for example - will determine what the optimal values of static weight, balance, SW, head size, etc. are for that player, I believe.
1.Some players like Chang used 27.5 inch long racket
2.The OP question was about speed
There some theory behind what I have said but it requires drawings
3.The problem depends on quality of serve/elevation/etc
There is a set of differential equations by Cross describing dynamics
4.There is a paper by Cross related to the subject above
5.I post more at tennisplayer.net
I meant racket head speedThanks, Julian, appreciate your drawing my attention to this very interesting topic.
BTW, regarding point 2 in your list, the OP refers to racquet head speed. Not sure if you mean the same thing... head heavy racquets are good for ball speed, but not RHS, I believe.
Thanks, Julian, appreciate your drawing my attention to this very interesting topic.
BTW, regarding point 2 in your list, the OP refers to racquet head speed. Not sure if you mean the same thing... head heavy racquets are good for ball speed, but not RHS, I believe.
What is RHS?
...spin?
What is justification of "but not RHS"?Thanks, Julian, appreciate your drawing my attention to this very interesting topic.
BTW, regarding point 2 in your list, the OP refers to racquet head speed. Not sure if you mean the same thing... head heavy racquets are good for ball speed, but not RHS, I believe.
Looking at the following comparison:
A) Static Weight: 12 ounces
Balance: Even
Swingweight: 330
B) Static Weight: 12 ounces
Balance: 6HL
Swingweight: 340
I will agree with corners on this, on second thoughts!
Are you saying that three numbers describing A CONTRADICT each other?If everything is measured correctly A would have the higher sw
If everything is measured correctly A would have the higher sw
What is justification of "but not RHS"?
Is it based on a two pendelum model/theory?
PS Two pendelum model is described in two references below
R. Cross, A double pendulum model of tennis strokes, Am. J. Phys. 79, 470-476 (2011). See also http://twu.tennis-warehouse.com/learning_center/doublependulum.php for videos of double pendulum action.
The article addresses rackets with THE EVEN balance with differentJulian, I have read this article. Maybe I am missing something, but it doesn't seem to relate the terminal velocity of a racquet to the racquet's properties.
Anyway, pendulum theory is interesting, and I have studied it in the distant past, but I don't believe it is directly applicable to what we are talking about here. Because in this case, the pendulum is not swinging passively in reaction to an external force (gravity) - its components (wrist, elbow, etc) are actively generating internal torque, in a manner that can only be described as uneven, to put it mildly!
Coming back to the question of a heavy racquet with large static moment and swingweight and how it responds to a force/torque: it takes a larger force to linearly accelerate a larger mass, and it takes a larger torque to angularly accelerate a larger swingweight. At every step of the way, there is either a linear force or a torque or both active, and when faced with a heavier mass or swingweight, the force/torque will produce less acceleration. Thus, for a given maximum force/torque, a lighter racquet (static weight and SW) can be made to move/rotate faster. If I am wrong, please tell me why.
BTW, the reason I hate large static moment is that I roughly equate it to the initial force/torque one needs to get it moving. Thus it's simply a drag on the arm, and the wrist in particular. But I suppose performance athletes will choose to live with whatever works for them when in competitions with large sums of money and prestige involved.
Just for the record I do NOT understand your post #37^^^ Got it, Julian - thanks. I will read at least some of these when I get a chance.
Just for the record I do NOT understand your post #37
I do NOT understand why the FIRST paper by Cross ( American Journal of
Physics) does NOT relate to OP
BTW:an arm is involved as one of pendelums-we have 2 pendelums,NOT ONE
I expanded my post #38
1.As indicated in one of my previous posts the double pendulum modelWell, I have never studied double pendulums (the single idealized pendulum I believe is easy enough to be a high school math/physics exercise). Also, I don't have access to Rod Cross' paper, and I certainly don't want to buy it for the $30 that it costs! Looking at wikipedia, it seems like the double pendulum is modeled using Lagrangian equations that can only be solved numerically - ouch! I am not too keen to get into all that again, so you'll have to excuse me.
But if you could provide a high level view of what answer it implies to the OP's question, I will be delighted.
My own view, admittedly very subjective, is that pendulum theory does not apply here because the nature of the forces involved are too different from gravity. I don't think I have any other insights or knowledge to warrant more posts on this subject...
1.As indicated in one of my previous posts the double pendulum model
is described in
http://twu.tennis-warehouse.com/learning_center/doublependulum.php
Another article is available for reading at
http://www.physics.usyd.edu.au/~cross/PUBLICATIONS/49. TennisDPend.pdf
You may go to
http://www.physics.usyd.edu.au/~cross/publications.html
It contains the list of publications.
Clicking the title brings the pdf file of a corresponding paper
I have checked that I can see the important Fig 5
2.We may discuss at some moment why the double pendulum applies here
So I disagree with your last sentence