Weighting up the Crossguard of my Sword

[mtommer]

The answer is yes. Will answer the why later.

But only if the weight is a specific amount, in a specific shape, placed very specifically on the handle...

 

[Slowtwitcher]

Try two frames;

One with

335sw, 32bal, 335g

and another with

325sw, 32bal, 335g

Given the same hand position, they do not swing the same. The 335sw frame swings slower.

Did you expect they felt the same?

 

[travlerajm]

I never said that a heavier racket wouldn't volley better. I do not know. I do not even know how to actually _measure_ if a given racket volleys better. It very well may be that a given player volleys better (whatever that means) with a heavier racket. However if it is so it is not because of this:
"
Punching forward with the hand forces the racquethead to come forward with the hand, generating solid momentum into your shot. Conversely, without this extra mass, a forward punch causes the racquethead to pivot backward in the wrong direction. Think of how Sampras volleys. Then think of how Roddick volleys. Compared to ARod, Pete has an extra 45g of bulk just above his handle that helps him to look more talented on the stabs and punches.
"
If you add weight to a racket above the point where you hold the racket you make the upper portion heavier. Which means it is harder to put in motion. When you push on a handle the upper part of the racket, because of added weight, 'wants' to stay in place due to inertia. That extra mass that will make the racquethead to pivot backward around the balance point more than it would have been the case without added weight (assuming all other aspects remained the same) - contrary to the above highlighted post. If you want to move the rackethead forward when you are 'punching forward with the hand' then you want the weight where the hand is, not above it. Consider orchestra director baton. The baton is made so the tip moves very easily and follows the movement of the hand. Where is the weight of the baton located (mostly) - at the very bottom, where the director holds it.

A few years ago, I posted an analysis of TW Racquet Review scores for 199 racquets reviewed. For volley performance rating, there was a very distinct and obvious trend, with the Volley Score directly proportional to MgR/I value of the racquet.

Although MgR/I is a Swing Dynamics property, it is also a useful proxy for Impact Dynamics, because under most conditions dynamic stiffness increases with MgR/I. The value typically ranges from between 20.0 to about 21.5.

In general, all of the racquetsb receiving exceptional Volley Score by the TW Review team had MgR/I in the 21.0 range, while racquets with MgR/I below 20.5 generally had poor Volley Score.

The trend for slice score was the same as the trend for volley score.

As a reference point, both Sampras and Edberg played with racquets having MgR/I of 21.0. Prime Federer at 21.0 too.

Most modern pros, including Djokovic and many next gen players, are using frames in the 20.3 range. Roddick was at 20.0.

 

[travlerajm]

This thread linked below, sadly, was lost in The Great TTW Server Crash of 2016. But it was later dug out of the grave a few years later. Unfortunately, upon revival, the links to my data figures were broken, and the data resides on my old laptop, which is on the other side of the equator from my current location.

The most salient point in the data is that the TW Review team (when their individual scores were averaged together) gave far superior Review Score in every single performance category, especially Overall Score, to those racquets that had MgR/I value in the 20.95-21.05 range (i.e. ~21.0).

https://tt.tennis-warehouse.com/index.php?threads/tw-racquet-review-ratings-vs-mgr-i-measurements.559553/#post-10171835

 

[am1899]

Your...sword?

 

[TennisD]

The more of an eyesore it is, the more people will notice it and ask why on earth he would do such a thing, which allows him to talk about it at great length.

J

The longer you can spend talking about your 'setup' in the clubhouse the less you have to play!

 

[taylor15]

Man, I just hit the ball back.

J

Funny coming from a guy who had >14oz sticks at one time

 

[jmnk]

I don't fully understand the physics, but I encourage you to actually try comparing racquets with the usage of proper tools to take the measurements (RDC, balance board, scale).

sure, I can do 'the measurements' with proper tools. What would you want me to measure?

I've played a decent level of tennis (Div1), so I am well attuned to feeling and understanding the differences. Try two frames;

One with

335sw, 32bal, 335g

and another with

325sw, 32bal, 335g

Given the same hand position, they do not swing the same.

sure they do not. Is someone claiming they do?

The 335sw frame swings slower. However, if you match pendulum acceleration, they come around exactly the same.

Before testing these concepts, I could not understand why my forehand always felt immediately "off" when raising swingweight, despite retaining balance.

Could you please define what is 'pendulum acceleration' in the context being described here?

 

[jmnk]

A few years ago, I posted an analysis of TW Racquet Review scores for 199 racquets reviewed. For volley performance rating, there was a very distinct and obvious trend, with the Volley Score directly proportional to MgR/I value of the racquet.

Although MgR/I is a Swing Dynamics property, it is also a useful proxy for Impact Dynamics, because under most conditions dynamic stiffness increases with MgR/I. The value typically ranges from between 20.0 to about 21.5.

In general, all of the racquetsb receiving exceptional Volley Score by the TW Review team had MgR/I in the 21.0 range, while racquets with MgR/I below 20.5 generally had poor Volley Score.

The trend for slice score was the same as the trend for volley score.

As a reference point, both Sampras and Edberg played with racquets having MgR/I of 21.0. Prime Federer at 21.0 too.

Most modern pros, including Djokovic and many next gen players, are using frames in the 20.3 range. Roddick was at 20.0.

This thread linked below, sadly, was lost in The Great TTW Server Crash of 2016. But it was later dug out of the grave a few years later. Unfortunately, upon revival, the links to my data figures were broken, and the data resides on my old laptop, which is on the other side of the equator from my current location.

The most salient point in the data is that the TW Review team (when their individual scores were averaged together) gave far superior Review Score in every single performance category, especially Overall Score, to those racquets that had MgR/I value in the 20.95-21.05 range (i.e. ~21.0).

https://tt.tennis-warehouse.com/index.php?threads/tw-racquet-review-ratings-vs-mgr-i-measurements.559553/#post-10171835

We have been over this MgR/I thing many, many times. There's an excellent math-backed analysis of this concept. With a _very_ telling title: https://tt.tennis-warehouse.com/index.php?threads/mgr-i-is-useless.352140/ (in case one is wondering the author of that thread, @stoneage, is the very same person that developed racquetTune app so I'm going to err on the side that he knows a thing or two). There's no point rehashing this. Anyone is obviously free to believe whatever.

 

[travlerajm]

We have been over this MgR/I thing many, many times. There's an excellent math-backed analysis of this concept. With a _very_ telling title: https://tt.tennis-warehouse.com/index.php?threads/mgr-i-is-useless.352140/ (in case one is wondering the author of that thread, @stoneage, is the very same person that developed racquetTune app so I'm going to err on the side that he knows a thing or two). There's no point rehashing this. Anyone is obviously free to believe whatever.

That thread is obsolete. Stoneage changed his mind on its utility and incorporated an MgR/I calculator in to his app.

 

[jmnk]

That thread is obsolete. Stoneage changed his mind on its utility and incorporated an MgR/I calculator in to his app.

please, that is such a misrepresentation. I'm really sorry you keep doing that - you seem a cool guy overall.
We have discussed Stoneage's view on this topic in the past:

I'm glad we can agree on the fact that @stoneage is a sharp dude. Let me however clarify:
he did not "eventually" (as in implying he did it _after_ he saw the light and understood MgR/I concept) add MgR/I calculator to his app. He did it almost immediately after you posted about it - just to make it easy on himself and other to measure MgR/I to see what it is all about. He never claimed it has any significance. in fact, to reflect what his view on the concept is, you should quote from his own posts in the thread where he announced the introduction of the MgR/I calculator:
"
I know there is no magical number, on the contrary I am rather skeptical to the concept. So I wrote the post to see if anyone could come up with an explanation why this is relevant. There were no good ones in the older post as far as I could see.
"
"
However, there is no discussion of MgR/I and no evidence why it should have any value. Except Travelrajm who jumps in says its great.
"
the above are from https://tt.tennis-warehouse.com/index.php?threads/measuring-mgr-i.351707/

[...]

MgR/I was never incorporated into his app. The calculator was for some time provided on his web site in 2010. Even that is no longer available as he apparently took it down. Perhaps he did change his mind - I'm certainly not privy to conversations you two may have had. It would be however a bit strange for him to publicly state quite the opposite a late as in 2013:

Thanks. Hopefully you and travlerajm can get together and work on mgr/i.
[...]

Sorry, but that is not going to happen.
I have tried both to get some useful information about what mgr/i is supposed to mean and to contribute, but the response has been discouraging to say the least.
[...]

 

[Shroud]

We have been over this MgR/I thing many, many times. There's an excellent math-backed analysis of this concept. With a _very_ telling title: https://tt.tennis-warehouse.com/index.php?threads/mgr-i-is-useless.352140/ (in case one is wondering the author of that thread, @stoneage, is the very same person that developed racquetTune app so I'm going to err on the side that he knows a thing or two). There's no point rehashing this. Anyone is obviously free to believe whatever.

It works for me after having tried the principle. No clue what the numbers work out to because i go by feel. But the idea works well in practice