Spin is better than Speed - I am a believer now.

[langel]

I did. The balls were 39.6mm and 40mm and the masses almost identical. These were controls so that the difference in properties of the material could be investigated. The effect of size or mass was not part of the study

Obviously you didn't.
In the particular study are mentioned referencies to other sudies and conclisions are made too.

But I refuse to debate on empty bases, as such a debate will be longer than the study and every answer on emty bases will provoke either other half-truths, or even false enterpretations.

 

[NDH]

Just read the abstract. Had some hard time to understand some words and if they came to any results. Could you explain shortly in an easier way?

Thanks.

It's one of those scientific reports that feels more science than reality.

There's a reason all the pros, the manufacturers and thousands of amateur players have all said they get less spin (in general) with the plastic ball compared with the celluloid ball....... They can't all be wrong just because one study attempts to prove otherwise......

I have no problem believing the report (which is saying the plastic ball generates more spin), but I just don't see those results in the real world.

It may be because a robot can generate more spin than a human can (consistently)....... But who knows......

 

[Joepole]

I think it's because people compare to a 38mm ball. This would clearly spin faster (conservation of angular momentum). As far as I'm aware there aren't any 38mm plastic balls or 40+ celluloid balls so it's all a bit academic really

 

[langel]

Blah-Blah for Bang-Bang

 

[NextLevel]

It's one of those scientific reports that feels more science than reality.

There's a reason all the pros, the manufacturers and thousands of amateur players have all said they get less spin (in general) with the plastic ball compared with the celluloid ball....... They can't all be wrong just because one study attempts to prove otherwise......

I have no problem believing the report (which is saying the plastic ball generates more spin), but I just don't see those results in the real world.

It may be because a robot can generate more spin than a human can (consistently)....... But who knows......

People aren't really talking about spin, they are talking about spin effect. And I think there are things that celluloid balls did when they contacted the racket with spin, either because of size or material deformation, that plastic balls don't do and that is what people interpret as having more or less spin. No one actually knows or measures the revolutions on the ball usually. And some people don't act like table tennis players when thinking through the issue and sometimes fail to get to the heart of the matter, arguing through physics about something without understanding that the table tennis phenomenon still needs a proper explanation.

 

[NextLevel]

I did. The balls were 39.6mm and 40mm and the masses almost identical. These were controls so that the difference in properties of the material could be investigated. The effect of size or mass was not part of the study

The Nittaku premium ball might be a smaller 40+ ball but it is still a 40+ ball. I think the article didn't really investigate what people really complain about.

 

[tt chats]

This study fits with my personal experience. Good to read.
I'm sure almost nobody will read it and as a result almost everybody will continuue to echo half-truth mantras.

https://www.researchgate.net/public...Plastic_on_the_Post-Collision_Ball_Trajectory

It's interesting. I've read the conclusion.
'... for faster balls with greater amounts of top-spin, plastic balls are expected to experience greater acceleration upon collision with the table than celluloid balls...'
Do you feel so?
Personally, I don't feel much about this.

 

[NextLevel]

It's interesting. I've read the conclusion.
'... for faster balls with greater amounts of top-spin, plastic balls are expected to experience greater acceleration upon collision with the table than celluloid balls...'
Do you feel so?
Personally, I don't feel much about this.

For the Nittaku Premium ball, it is a reasonable conclusion.

 

[yogi_bear]

You mean the kicking effect comparison of poly and celluloid balls?

 

[NextLevel]

No one cares about the kicking effect per se. What people care about is that all of a sudden, they need to play more shots to win a point. And they need to put in much more effort to get people to block their topspins long.

 

[vvk1]

No one cares about the kicking effect per se. What people care about is that all of a sudden, they need to play more shots to win a point. And they need to put in much more effort to get people to block their topspins long.

Somewhere in Canada, Adam Sharara is reading this post on his iPad, and thinking "yesss, finally TT forum people see why we had to switch to plastic balls".

 

[Zeen]

It's one of those scientific reports that feels more science than reality.

There's a reason all the pros, the manufacturers and thousands of amateur players have all said they get less spin (in general) with the plastic ball compared with the celluloid ball....... They can't all be wrong just because one study attempts to prove otherwise......

I have no problem believing the report (which is saying the plastic ball generates more spin), but I just don't see those results in the real world.

It may be because a robot can generate more spin than a human can (consistently)....... But who knows......

What? How did you come up with that implication? In fact, the study says nothing at all about which ball generates more spin.

What is says though, is that plastic balls experience more friction when contacting the table. Especially when the ball is rotating, the increased friction causes the ball to experience a force in the same direction the ball is spinning. So where does this force come from? Thin air? No, it comes from the rotation energy, which in turn is diminished.

IN FACT THIS STUDY PROVES THAT PLASTIC BALLS HAVE LESS SPIN COMPARED TO CELLULOID BALLS.

With the following caveats:
(1) As experienced by the opponent on their rubber
(2) Assuming that the plastic ball's initial spin rate, with the usual range of strokes a player has, is not so much higher that it overcompensates the spin loss due to friction on the table.

There you have it. Show it to all the fools who still live in denial.

 

[yogi_bear]

Whether people care or not is beside the point of my question. I was clarifying the statement of tt chats.

QUOTE=NextLevel;273188]No one cares about the kicking effect per se. What people care about is that all of a sudden, they need to play more shots to win a point. And they need to put in much more effort to get people to block their topspins long.[/QUOTE]

 

[usualsuspect]

This study fits with my personal experience. Good to read.
I'm sure almost nobody will read it and as a result almost everybody will continuue to echo half-truth mantras.

https://www.researchgate.net/public...Plastic_on_the_Post-Collision_Ball_Trajectory

Interesting study. This proves most of what everyone already knows.
Celluloid balls retain spins much better than plastic balls.
Under similar amount of topspin, plastic balls have better "kick" effect than celluloid balls, presumably by having a rougher surface.
However, this study does not provide insight into whether the same amount of energy will produce similar amount of spin/rotations on celluloid balls and plastic balls.

I surmise what most players feel about plastic balls is in line with this study. Plastic balls' less spin is due to them losing spins more rapidly than celluloid balls. I also think it takes more energy to impart the same amount of spin on plastic balls, compared to celluloid (not supported by the study).
Plastic balls being slower is due to their larger size and lower density (larger mean size, but lower mean mass than celluloid according to the study). This means air friction will have much more effect on plastic balls than on celluloid, so plastic balls loses velocity faster than celluloid.

 

[brokenball]

I have read the researchgate document. The simulation they did is similar to one I did 5 or more years ago. It looks good to me.

What I notice is that the plastic balls seem harder or more brittle than the celluloid balls. The plastic balls are less likely to deform or dimple as I squeeze them. That would make a huge difference in the amount of surface area of the ball that is in contact with the paddle or the table when impact occurs.

 

[yogi_bear]

Did they measure the spin before and after the bounce comparing both balls?

 

[usualsuspect]

Unfortunately, no. Only spin before bounce/collision was calculated based on how long it took for the ball to complete a single rotation. This was used to calculate the coefficient of friction during analysis part of the study.

All this study shows is that under similar initial velocity and spin, plastic balls have higher coefficient of restitution, which told us plastic balls bounce better than celluloid, and higher coefficient of friction, which told us that plastic balls are affected more by spin when colliding on the table.
This study is quite unsatisfying because it didn't look into the difference in the amount of energy required to impart the same initial velocity and spin between celluloid and plastic balls.

 

[Atas Newton]

Somewhere in Canada, Adam Sharara is reading this post on his iPad, and thinking "yesss, finally TT forum people see why we had to switch to plastic balls".

Adam Sharara when he found out the changes aren't popular with the players:

 

[vvk1]

Adam Sharara when he found out the changes aren't popular with the players:

Good one!

Though I must admit to growing to like the changes brought about by plastic balls - that it's now harder to win a point quickly, that longer rallies are required, that one needs to be more physically fit to play as an attacker, etc - feels like I became a better player as a result.

 

[NextLevel]

Good one!

Though I must admit to growing to like the changes brought about by plastic balls - that it's now harder to win a point quickly, that longer rallies are required, that one needs to be more physically fit to play as an attacker, etc - feels like I became a better player as a result.

My brain sometimes agrees with you but my body doesn't.