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PostPosted: 16 Dec 2008, 03:38 
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antipip wrote:
Adham: My point about stamping or stomping as you put it was more to do with what I would call ungentlemanly conducty or a lack of sprotmanship and how it affects the perception of the game. I think it gives the game a bad image.
I don't doubt it's a learned technique, but I don't believe it is a neccesary one in the execuution of any shot.

You raised the point of it been used to cover up the sound of which racket side is used and this been less important since the introduction of the 2 colour rule. You will find that if you really listen you can tell how it was hit not just which side was used, so they are also gaining by covering up information. I am more concerned with what I see as unsporting behaviour and its affect on the image of the game rather than this loss of information.

On the serve issue: Whilst I have no access to table tennis studies, I have seen some with other racket sports. These show that elite performers attend to the servers wrist not the actual racket as many of the performers themselves and others think.

Have such studies been done in table tennis? If not they should be done. If they poduce the same results as other racket sports the implication would be clear. The receiver would need to see the wrist at and before impact of the server not just the racket at the point of contact to not be disadvataged. I would hypothesise that the present rule and how it's implemented gives the server too much of an advantage. If no studies have been done, based on your comments earlier in this thread that the service was not wanted to give to much of an advantage; I would suggest you do some studies and based on those findings you can leave or alter the rule.


Stomping or stamping: we currently have no complaints from the players, and frankly you are the first one to bring it to my attention as "unsporting" behaviour. In any case, I will look more into it.

Regarding your pint about the wrist. In fact, that could be a problem if the focus is on the wrist alone. As you know most service action now is a double action, the wrist goes in one direction and then back. But the ball is contacted only at one of these two actions. If your focus is on the wrsit alone, you would never know what spin is coming, it would be a 50%-50% guess. However, if you can see the point of contact, then you would know which of the two actions actually touched the ball and hence you would know the spin. Further, the same action could contact the ball in the North hemishpere (Top-spin) or in the south hemisphere of the ball (chop), so basically, putting side-spin aside, there are 4 possible spin combinations with one service. Focusing on the wrost would not give you this information. An added factor od course is "no spin" and "side sspin". The latter totally depends on the point of contact, while the former depends a lot on the trajectory of the ball. A good service return depends on knowing and understanding the following:
- servers point of contact (where is ball touched?)
- direction of the racket of server when actually making contact with the ball (2 directions on each serve, only one makes contact)
- angle (real) of opponent when making contact with the ball (players will change angle just at the point of contact to send the wrong information)

Other racket sports do not have a double action, only one action, so of course looking at the wrist helps a lot. In Squash and Badminton spin is not a factor on the service, "position and placement" is more important. In Tennis there is spin, but power is the most important on the first serve, plus the service is completely visible.

many studies have been done on the TT service. The Chinese of course are the most proficient and they introduced many many years ago the variation of spin on the service by making the same motion but contacting the ball at different spots (south and north). The also introduced the "high-toss" serve, gaining momentum (kinetic energy) from a descending ball after it reached it's peak. The higher the toss, the more kinetic energy released at the point of contact close to the table after the ball descended. In Europe, Czila Batorfi perfected the high toss serve, originally invented and introduced internationally by Hsu Shaofa (or Xu Shaofa) more than 35 years ago.

I hope this explanation helps somehow.

Adham

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PostPosted: 16 Dec 2008, 03:43 
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adham wrote:
Glueless wrote:
adham wrote:
The problem in returning service is not so much the quantity of spin, the problem is to know the and recognize the amount and type of spin. If you can see the point of contact, and if you can see the direction of the toss, then it's rather easy to know the amount and type of spin. This is why I keep insisting about the "intent" of the rule. The main intent is "a clear view for the receiver", as long as that is achieved, then the players are happy. As long as they can see the point of contact then it's OK for them.


This would eliminate the need for the 'nearly vertical' portion of the rule. If I understand correctly, as long as I toss the ball at least 15cm in the vertical and do it so that the toss and contact point are perfectly visible to my opponent, then I have met the 'intent' of the rule and the angle at which I toss the ball is irrelevant.

I'm more confused now than ever. :oops:


Don't be confused. The necessity of the wording "nearly vertical" is to avoid one particular situation, whereas players where throwing the ball high, but to the side, and as the ball descended, they shielded it with the left shoulder (for right handed server). The ball was visible to the umpire all the time, but was shielded from the receiver just before the point of contact.


Adham,

Thank you for the kind response!

In my example I mentioned that the toss of my serve and contact point would be visible to the opponent. No shoulder in the way at all. No point of the toss or contact point is blocked from the opponent at any point during the service.

Would this service be legal regardless of the angle of my toss?

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PostPosted: 16 Dec 2008, 03:43 
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Berenger wrote:
adham wrote:
haggisv wrote:
adham wrote:
- perhaps you are talking about oils and vegetable based tuners, these of course are not harmful to the health. The problem is that they alter the rubber after approval.
Adham


I'm sorry to keep questioning this, but I'm still unconvinced of the explanation...

1. Lets assume we have a VOC-free poison-free booster. The factory glues an ITTF approved topsheet onto a sponge. Now the factory uses a booster on the SPONGE ONLY. Now according to all evidence I've seen, the ONLY effect that the booster has on the TOPSHEET is that it stretches it, which according to you is legal when done in the factory (within ITTF set limits). Sponges are already made with the use of chemical, and are also glued to the topsheet using VOC-based chemical, so the booster is simply part of this factory process. The rubber is aired properly before sold to the public. Legal rubber or not?

2. Lets assume we have a VOC-free poison-free booster. The factory uses a booster on the sponge, BEFORE it's glued onto an ITTF approved topsheet. The rubber is aired properly before sold to the public. Legal rubber or not?

3. A distributor buys a cheap ITTF approved topsheet and a sponge, and applies either on the the methods (1. or 2.) above. This turns a cheap chinese topsheet and sponge combination into a rubber of similar performance to the top-end Tensor style rubber. The rubber is aired properly before sold to the public. Legal or not?

4. A player buys a cheap topsheet and sponge, and applies either on the the methods (1. or 2.) above. This turns his cheap chinese topsheet and sponge combination into a rubber of similar performance to the top-end Tensor style rubber. Legal or not?

Please understand I have no problem in accepting your speed glue ban, for health reasons. I also would have no problem in accepting the booster/tuner ban if you gave us a reason why, since the health issue is not proven.

If you said it was in order to slow the game down, I would accept that as a valid reason, even if I didn't agree with it...
The bit I'm not happy with is that the ITTF trying to justify the banning of tuners/booster, by saying that they are already against existing rules... this is a means of banning them, not a reason... I hope you can see the difference...


In order to answer your 4 scenarios, first I will explain clearly the rule:
- Any post-factory alteration of the equipment (in this case racket covering) is NOT legal. By post-factory, we mean at the distributor level, at the retail level, at the player level, at the reseller level, etc.
- VOC-containing glues are used at the factory level for several applications (gluing the rubber to the sponge, gluing the wood plies to make the racket, etc.). The factory must follow the rules of their government as it relates to VOCs (very strict in Japan, Canada, Germany,etc, but rather lax in China, India, Russia, etc.). In any case, the ITTF advices the factories to air and ventilate the equipment (rackets and racket coverings in this case) using special ventilated racks, which usually eliminate all VOCs (or almost all).
So now, you could answer your questions yourself:

1. Legal (at factory, no VOCs, no poison, properly aired, stretched within limits).
2. Legal (same as above, if I understood correctly)
3. Post factory, not legal
4. Post factory, not legal

The above is according to the current rules (if I understood the scenarios correctly).

I understand your position about VOC-glues. Regarding the so-called vegetable-based tuners and boosters that are free of VOC and poison, I really do not see any harm in accepting them. But what I keep repeating is that according to our current rules they are "illegal" because they alter the racket covering. This is NOT according to our rules and never was. Rule 2.4 is clear about the composition of the racket, but since some felt it was not clear enough, rule 2.4.7 was proposed by those that sought further clarity. This makes any type of additive, whether healthy or not, illegal. Now let's talk practically. Is it detectable? Probably not, unless it makes the rubber bulge too much and exceeds 4mm, or if it makes the rubber bulge and the surface is not flat. So as you can see it may cause 2 infractions to the current rules. I anticipate your next question: suppose I use VOC-free, non-poisonous, vegetable based substance on the sponge, and the total thickness of the racket covering does not exceed 4mm, and the surface is flat, is it legal or illegal? The answer is it is still illegal because you are not supposed to have any additives according to 2.4 (not part of the composition of the racket) post-factory, but would be totally acceptable, because no apparent rule would be violated. In fact, this could be the future direction, but the question is, would you still have the same effect? Less than 4mm thick, surface flat (no bulge or dome), would there be any reason to do this?

Please believe that the rules are not purposely intended to slow down the game. The speed of the game depends on the players. Sure, a side effect of the 40mm ball and the VOC-free glue, and the booster and tuner ban does make the game slower. But speed is not really the issue. You could get more speed by making the blades faster to compensate in the loss of speed. In fact, my recommendation to the top players and to the manufacturers is to always look at the racket as a whole: blade wood type, blade weight, blade distribution of weight, sponge type and thickness and rubber type. The sum of the total combination of all those elements is what should give the player the amount of speed he/she desires, the amount of friction (spin) they desire, and the amount of "feel" they desire.

I hope I answered your questions, I am not trying to convince you, just trying to explain.

Adham


Dear Adham,

I'm Laurent Bérenger, I produced boosters for many brands and member of FIT.

The ITTF seems to be in war against boosters an other chemical stuff. From my knowledge, and you confirmed it (point 1 of your answer), there is no rule against placing a sponge if this sponge, boosed or not, doesn't modify the charachteristics of the topsheet.

but I'm surprised by your answer "post factory". According to my knowledge, once again, I don't see any rule witch prohibit a player removing sponge from the topsheet and past this original and not modified topsheet with another or with the same sponge (boosted or not).

Also, when topsheet and sponge are selling separately, is there any rule witch prohibit to boost the sponge before gluing it on the approved and not modified topsheet?

These last 2 cases, the topsheet keeps originals characteristics (nb of pimples by cm² , thickness, elasticity, pimple size, logo size and so on...)

The ITTF shouldn't be on war against boosters because not illegal if palyers or manufacturers respect differents steps for, finally have the same topsheet as approved.

Anybody can use a car if he doesn't drive too quick. Anybody can use a booster if he doens't modify the topsheet.

I'm looking formard to your answer,

very friendly yours,

Laurent Bérenger

(sorry for my english, I hope I'm clear enough!)


Thanks for your post. First, the ITTF is not at war about anything. But before I answer your question, please answer me one question so that I better understand: "If the booster has no effect on the top sheet, then why use a booster at all?"

I also suggest that you read carefully the section of ITTF rules regarding the Racket (2.4). The composition of the racket is very clear. There is no allowance for any additives. Boosters would be considered an additive, by the current rules.

Adham

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PostPosted: 16 Dec 2008, 03:53 
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Glueless wrote:
adham wrote:
Glueless wrote:
adham wrote:
The problem in returning service is not so much the quantity of spin, the problem is to know the and recognize the amount and type of spin. If you can see the point of contact, and if you can see the direction of the toss, then it's rather easy to know the amount and type of spin. This is why I keep insisting about the "intent" of the rule. The main intent is "a clear view for the receiver", as long as that is achieved, then the players are happy. As long as they can see the point of contact then it's OK for them.


This would eliminate the need for the 'nearly vertical' portion of the rule. If I understand correctly, as long as I toss the ball at least 15cm in the vertical and do it so that the toss and contact point are perfectly visible to my opponent, then I have met the 'intent' of the rule and the angle at which I toss the ball is irrelevant.

I'm more confused now than ever. :oops:


Don't be confused. The necessity of the wording "nearly vertical" is to avoid one particular situation, whereas players where throwing the ball high, but to the side, and as the ball descended, they shielded it with the left shoulder (for right handed server). The ball was visible to the umpire all the time, but was shielded from the receiver just before the point of contact.


Adham,

Thank you for the kind response!

In my example I mentioned that the toss of my serve and contact point would be visible to the opponent. No shoulder in the way at all. No point of the toss or contact point is blocked from the opponent at any point during the service.

Would this service be legal regardless of the angle of my toss?


With all the conditions you mentioned, in ITTF events, the umpires do tolerate a toss that is about half way between the vertical and the horizontal, so nearer to 45% than 90%, so as long as your toss is not at the 180% level (0%), but nearer to 45% then it is currently tolerated. As I said in previous posts, this is at ITTF events and as long as the umpire does no see any unfair advantage being taken.

One very important point. I will never umpire any of your matches, so you have to accept the decision of the umpires that umpire your matches, right? Some are very strict and some are more lax. You have to serve according to the rule, and through experience you know the degree of tolerance accepted, but you can't throw the ball horizontally backward and claim that your service is legal because the point of contact is visible. here is my advice:
- Serve exactly as you described (all is clear to receiver) and stay within the 45% and 90% vertical.
- If you have a very strict umpire, then stay closer to the 90% vertical.
- Use common sense

But if I were you, I would spend more time on developing spin variations in my serves (using wrist, finger pressure, forearm acceleration, varying point of contacts, trunck rotation, etc.) - also see a previous post about this.

It is very difficult to explain this in writing, so I hope you get the gist of it.

Adham

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PostPosted: 16 Dec 2008, 04:59 
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adham wrote:

Dear Adham,

I'm Laurent Bérenger, I produced boosters for many brands and member of FIT.

The ITTF seems to be in war against boosters an other chemical stuff. From my knowledge, and you confirmed it (point 1 of your answer), there is no rule against placing a sponge if this sponge, boosed or not, doesn't modify the charachteristics of the topsheet.

but I'm surprised by your answer "post factory". According to my knowledge, once again, I don't see any rule witch prohibit a player removing sponge from the topsheet and past this original and not modified topsheet with another or with the same sponge (boosted or not).

Also, when topsheet and sponge are selling separately, is there any rule witch prohibit to boost the sponge before gluing it on the approved and not modified topsheet?

These last 2 cases, the topsheet keeps originals characteristics (nb of pimples by cm² , thickness, elasticity, pimple size, logo size and so on...)

The ITTF shouldn't be on war against boosters because not illegal if palyers or manufacturers respect differents steps for, finally have the same topsheet as approved.

Anybody can use a car if he doesn't drive too quick. Anybody can use a booster if he doens't modify the topsheet.

I'm looking formard to your answer,

very friendly yours,

Laurent Bérenger

(sorry for my english, I hope I'm clear enough!)


Thanks for your post. First, the ITTF is not at war about anything. But before I answer your question, please answer me one question so that I better understand: "If the booster has no effect on the top sheet, then why use a booster at all?"

I also suggest that you read carefully the section of ITTF rules regarding the Racket (2.4). The composition of the racket is very clear. There is no allowance for any additives. Boosters would be considered an additive, by the current rules.

Adham[/quote]

Dear Adham,

A booster has an effect on the sponge of course... We can get better effect when a booster is used on a complete rubber because it stretch the topsheet too (illegal), but a streched sponge (alone) gives more "speed"... I guess you know that the same topsheet on different sponge gives differents results...

Second on the handbook (http://www.ittf.com/ittf_handbook/ittf_hb.html) ITTF explains that a racket covering is a layer of a rubber and cellular rubber (summary). But what is a rubber?? The technical leaflet (http://www.ittf.com/ittf_equipment/pdf/ ... s_2007.pdf) gives thes definitions as "any any material that can be stretched at room temperature to twice its original length, and that, after being held in the stretched state for one minute, retracts within one further minute to less than 1.5 times its original length."

so the sponge could be any material (booster included) if the final result can be stretched at room temperature to twice its original length, and that, after being held in the stretched state for one minute, retracts within one further minute to less than 1.5 times its original length....

Also, you told me that you don't allow any additive. Why did you confirlmed that manufacturers can do it? Remember:

haggisv wrote:

1. Lets assume we have a VOC-free poison-free booster. The factory glues an ITTF approved topsheet onto a sponge. Now the factory uses a booster on the SPONGE ONLY. Now according to all evidence I've seen, the ONLY effect that the booster has on the TOPSHEET is that it stretches it, which according to you is legal when done in the factory (within ITTF set limits). Sponges are already made with the use of chemical, and are also glued to the topsheet using VOC-based chemical, so the booster is simply part of this factory process. The rubber is aired properly before sold to the public. Legal rubber or not?

2. Lets assume we have a VOC-free poison-free booster. The factory uses a booster on the sponge, BEFORE it's glued onto an ITTF approved topsheet. The rubber is aired properly before sold to the public. Legal rubber or not?


And you answered:
1. Legal (at factory, no VOCs, no poison, properly aired, stretched within limits).
2. Legal (same as above, if I understood correctly)

you just justify that a players can remove the sponge from the topsheet to do it because of "post factory". Witch law prohibit that and talk about "post factory"?

So once again witch law prohibit somebody to remove the sponge from the topsheet, tune the sponge with any material if this material is still or become cellular rubber as described on the technical leaflet and handbook an re-glue on the topsheet witch is exactly as approved?

Thanks in advance!

Best regards,

Laurent Bérenger


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PostPosted: 16 Dec 2008, 05:10 
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Berenger wrote:
adham wrote:

Dear Adham,

I'm Laurent Bérenger, I produced boosters for many brands and member of FIT.

The ITTF seems to be in war against boosters an other chemical stuff. From my knowledge, and you confirmed it (point 1 of your answer), there is no rule against placing a sponge if this sponge, boosed or not, doesn't modify the charachteristics of the topsheet.

but I'm surprised by your answer "post factory". According to my knowledge, once again, I don't see any rule witch prohibit a player removing sponge from the topsheet and past this original and not modified topsheet with another or with the same sponge (boosted or not).

Also, when topsheet and sponge are selling separately, is there any rule witch prohibit to boost the sponge before gluing it on the approved and not modified topsheet?

These last 2 cases, the topsheet keeps originals characteristics (nb of pimples by cm² , thickness, elasticity, pimple size, logo size and so on...)

The ITTF shouldn't be on war against boosters because not illegal if palyers or manufacturers respect differents steps for, finally have the same topsheet as approved.

Anybody can use a car if he doesn't drive too quick. Anybody can use a booster if he doens't modify the topsheet.

I'm looking formard to your answer,

very friendly yours,

Laurent Bérenger

(sorry for my english, I hope I'm clear enough!)


Thanks for your post. First, the ITTF is not at war about anything. But before I answer your question, please answer me one question so that I better understand: "If the booster has no effect on the top sheet, then why use a booster at all?"

I also suggest that you read carefully the section of ITTF rules regarding the Racket (2.4). The composition of the racket is very clear. There is no allowance for any additives. Boosters would be considered an additive, by the current rules.

Adham


Dear Adham,

A booster has an effect on the sponge of course... We can get better effect when a booster is used on a complete rubber because it stretch the topsheet too (illegal), but a streched sponge (alone) gives more "speed"... I guess you know that the same topsheet on different sponge gives differents results...

Second on the handbook (http://www.ittf.com/ittf_handbook/ittf_hb.html) ITTF explains that a racket covering is a layer of a rubber and cellular rubber (summary). But what is a rubber?? The technical leaflet (http://www.ittf.com/ittf_equipment/pdf/ ... s_2007.pdf) gives thes definitions as "any any material that can be stretched at room temperature to twice its original length, and that, after being held in the stretched state for one minute, retracts within one further minute to less than 1.5 times its original length."

so the sponge could be any material (booster included) if the final result can be stretched at room temperature to twice its original length, and that, after being held in the stretched state for one minute, retracts within one further minute to less than 1.5 times its original length....

Also, you told me that you don't allow any additive. Why did you confirlmed that manufacturers can do it? Remember:

haggisv wrote:

1. Lets assume we have a VOC-free poison-free booster. The factory glues an ITTF approved topsheet onto a sponge. Now the factory uses a booster on the SPONGE ONLY. Now according to all evidence I've seen, the ONLY effect that the booster has on the TOPSHEET is that it stretches it, which according to you is legal when done in the factory (within ITTF set limits). Sponges are already made with the use of chemical, and are also glued to the topsheet using VOC-based chemical, so the booster is simply part of this factory process. The rubber is aired properly before sold to the public. Legal rubber or not?

2. Lets assume we have a VOC-free poison-free booster. The factory uses a booster on the sponge, BEFORE it's glued onto an ITTF approved topsheet. The rubber is aired properly before sold to the public. Legal rubber or not?


And you answered:
1. Legal (at factory, no VOCs, no poison, properly aired, stretched within limits).
2. Legal (same as above, if I understood correctly)

you just justify that a players can remove the sponge from the topsheet to do it because of "post factory". Witch law prohibit that and talk about "post factory"?

So once again witch law prohibit somebody to remove the sponge from the topsheet, tune the sponge with any material if this material is still or become cellular rubber as described on the technical leaflet and handbook an re-glue on the topsheet witch is exactly as approved?

Thanks in advance!

Best regards,

Laurent Bérenger[/quote]

Your question was very clear and my answer was very clear. "Additive" means to "ADD". Post factory this is illegal. At the factory, if the process of making the sponge follows the ITTF directives and the actual sponge leaves the factory free of VOCs, free of any poison, and the sponge itself will not alter the characteristics of any other component of the racket, and only the components as listed in 2.4 exist, then it would be OK. Anything else is not legal. This is very clear and according to our current rules. In fact, you should read "post-factory" as "post-production". This also applies to VOCs.

By the way, why are you corresponding with me in the Forum, I only come here occasionally. You can correspond directly with me at my private e-mail which you have and it is always my pleasure to answer you as I always do and also to meet you whenever possible. Please feel free to write to me directly.

Adham

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PostPosted: 16 Dec 2008, 09:26 
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Wow, that is real enlightening. I dun mind the hassle of following the discussion which might at times be lengthy. The whole thing is itself professionalism!

Keep up the good spirit guys, but be open and keep to the issue! Wish to salute all of you in this discussion.
:) :P :D

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PostPosted: 16 Dec 2008, 09:36 
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adham wrote:
Berenger wrote:
adham wrote:

Dear Adham,

I'm Laurent Bérenger, I produced boosters for many brands and member of FIT.

The ITTF seems to be in war against boosters an other chemical stuff. From my knowledge, and you confirmed it (point 1 of your answer), there is no rule against placing a sponge if this sponge, boosed or not, doesn't modify the charachteristics of the topsheet.

but I'm surprised by your answer "post factory". According to my knowledge, once again, I don't see any rule witch prohibit a player removing sponge from the topsheet and past this original and not modified topsheet with another or with the same sponge (boosted or not).

Also, when topsheet and sponge are selling separately, is there any rule witch prohibit to boost the sponge before gluing it on the approved and not modified topsheet?

These last 2 cases, the topsheet keeps originals characteristics (nb of pimples by cm² , thickness, elasticity, pimple size, logo size and so on...)

The ITTF shouldn't be on war against boosters because not illegal if palyers or manufacturers respect differents steps for, finally have the same topsheet as approved.

Anybody can use a car if he doesn't drive too quick. Anybody can use a booster if he doens't modify the topsheet.

I'm looking formard to your answer,

very friendly yours,

Laurent Bérenger

(sorry for my english, I hope I'm clear enough!)


Thanks for your post. First, the ITTF is not at war about anything. But before I answer your question, please answer me one question so that I better understand: "If the booster has no effect on the top sheet, then why use a booster at all?"

I also suggest that you read carefully the section of ITTF rules regarding the Racket (2.4). The composition of the racket is very clear. There is no allowance for any additives. Boosters would be considered an additive, by the current rules.

Adham


Dear Adham,

A booster has an effect on the sponge of course... We can get better effect when a booster is used on a complete rubber because it stretch the topsheet too (illegal), but a streched sponge (alone) gives more "speed"... I guess you know that the same topsheet on different sponge gives differents results...

Second on the handbook (http://www.ittf.com/ittf_handbook/ittf_hb.html) ITTF explains that a racket covering is a layer of a rubber and cellular rubber (summary). But what is a rubber?? The technical leaflet (http://www.ittf.com/ittf_equipment/pdf/ ... s_2007.pdf) gives thes definitions as "any any material that can be stretched at room temperature to twice its original length, and that, after being held in the stretched state for one minute, retracts within one further minute to less than 1.5 times its original length."

so the sponge could be any material (booster included) if the final result can be stretched at room temperature to twice its original length, and that, after being held in the stretched state for one minute, retracts within one further minute to less than 1.5 times its original length....

Also, you told me that you don't allow any additive. Why did you confirlmed that manufacturers can do it? Remember:

haggisv wrote:

1. Lets assume we have a VOC-free poison-free booster. The factory glues an ITTF approved topsheet onto a sponge. Now the factory uses a booster on the SPONGE ONLY. Now according to all evidence I've seen, the ONLY effect that the booster has on the TOPSHEET is that it stretches it, which according to you is legal when done in the factory (within ITTF set limits). Sponges are already made with the use of chemical, and are also glued to the topsheet using VOC-based chemical, so the booster is simply part of this factory process. The rubber is aired properly before sold to the public. Legal rubber or not?

2. Lets assume we have a VOC-free poison-free booster. The factory uses a booster on the sponge, BEFORE it's glued onto an ITTF approved topsheet. The rubber is aired properly before sold to the public. Legal rubber or not?


And you answered:
1. Legal (at factory, no VOCs, no poison, properly aired, stretched within limits).
2. Legal (same as above, if I understood correctly)

you just justify that a players can remove the sponge from the topsheet to do it because of "post factory". Witch law prohibit that and talk about "post factory"?

So once again witch law prohibit somebody to remove the sponge from the topsheet, tune the sponge with any material if this material is still or become cellular rubber as described on the technical leaflet and handbook an re-glue on the topsheet witch is exactly as approved?

Thanks in advance!

Best regards,

Laurent Bérenger


Your question was very clear and my answer was very clear. "Additive" means to "ADD". Post factory this is illegal. At the factory, if the process of making the sponge follows the ITTF directives and the actual sponge leaves the factory free of VOCs, free of any poison, and the sponge itself will not alter the characteristics of any other component of the racket, and only the components as listed in 2.4 exist, then it would be OK. Anything else is not legal. This is very clear and according to our current rules. In fact, you should read "post-factory" as "post-production". This also applies to VOCs.

By the way, why are you corresponding with me in the Forum, I only come here occasionally. You can correspond directly with me at my private e-mail which you have and it is always my pleasure to answer you as I always do and also to meet you whenever possible. Please feel free to write to me directly.

Adham[/quote]

Dear Adham

As suggested by speedplay, could we continue on this forum because a lot of players are concerned by this matter?

In fact my question was clear but you didn't answer... Additive on the factory step is legal because the sponge leaves the factory VOC free (so why advice aring the rubber for 72 hours??), free of poison (don't see any rule about it but I agree), and because the sponge itsel doesn't modify the top sheet and made by components listed on 2.4 (and because a rubber is any material with an minimum of elasticity, it is more difficult to break this law than follow it). OK! I get it!

But my question was: witch rule prohibits doing it post-production?? I really don't see it.. Please let me know witch chapter on the hanbook allows manufacturers to do it and prohibits it after the production step.

Also, topsheet can be sold alone. Witch rule prohibits to apply a cellular material boosted and VOC free??

Thanks in advance for your answer.

Best regards,

Laurent Bérenger


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PostPosted: 16 Dec 2008, 10:25 
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Berenger wrote:
adham wrote:
Berenger wrote:
adham wrote:

Dear Adham,

I'm Laurent Bérenger, I produced boosters for many brands and member of FIT.

The ITTF seems to be in war against boosters an other chemical stuff. From my knowledge, and you confirmed it (point 1 of your answer), there is no rule against placing a sponge if this sponge, boosed or not, doesn't modify the charachteristics of the topsheet.

but I'm surprised by your answer "post factory". According to my knowledge, once again, I don't see any rule witch prohibit a player removing sponge from the topsheet and past this original and not modified topsheet with another or with the same sponge (boosted or not).

Also, when topsheet and sponge are selling separately, is there any rule witch prohibit to boost the sponge before gluing it on the approved and not modified topsheet?

These last 2 cases, the topsheet keeps originals characteristics (nb of pimples by cm² , thickness, elasticity, pimple size, logo size and so on...)

The ITTF shouldn't be on war against boosters because not illegal if palyers or manufacturers respect differents steps for, finally have the same topsheet as approved.

Anybody can use a car if he doesn't drive too quick. Anybody can use a booster if he doens't modify the topsheet.

I'm looking formard to your answer,

very friendly yours,

Laurent Bérenger

(sorry for my english, I hope I'm clear enough!)


Thanks for your post. First, the ITTF is not at war about anything. But before I answer your question, please answer me one question so that I better understand: "If the booster has no effect on the top sheet, then why use a booster at all?"

I also suggest that you read carefully the section of ITTF rules regarding the Racket (2.4). The composition of the racket is very clear. There is no allowance for any additives. Boosters would be considered an additive, by the current rules.

Adham


Dear Adham,

A booster has an effect on the sponge of course... We can get better effect when a booster is used on a complete rubber because it stretch the topsheet too (illegal), but a streched sponge (alone) gives more "speed"... I guess you know that the same topsheet on different sponge gives differents results...

Second on the handbook (http://www.ittf.com/ittf_handbook/ittf_hb.html) ITTF explains that a racket covering is a layer of a rubber and cellular rubber (summary). But what is a rubber?? The technical leaflet (http://www.ittf.com/ittf_equipment/pdf/ ... s_2007.pdf) gives thes definitions as "any any material that can be stretched at room temperature to twice its original length, and that, after being held in the stretched state for one minute, retracts within one further minute to less than 1.5 times its original length."

so the sponge could be any material (booster included) if the final result can be stretched at room temperature to twice its original length, and that, after being held in the stretched state for one minute, retracts within one further minute to less than 1.5 times its original length....

Also, you told me that you don't allow any additive. Why did you confirlmed that manufacturers can do it? Remember:

haggisv wrote:

1. Lets assume we have a VOC-free poison-free booster. The factory glues an ITTF approved topsheet onto a sponge. Now the factory uses a booster on the SPONGE ONLY. Now according to all evidence I've seen, the ONLY effect that the booster has on the TOPSHEET is that it stretches it, which according to you is legal when done in the factory (within ITTF set limits). Sponges are already made with the use of chemical, and are also glued to the topsheet using VOC-based chemical, so the booster is simply part of this factory process. The rubber is aired properly before sold to the public. Legal rubber or not?

2. Lets assume we have a VOC-free poison-free booster. The factory uses a booster on the sponge, BEFORE it's glued onto an ITTF approved topsheet. The rubber is aired properly before sold to the public. Legal rubber or not?


And you answered:
1. Legal (at factory, no VOCs, no poison, properly aired, stretched within limits).
2. Legal (same as above, if I understood correctly)

you just justify that a players can remove the sponge from the topsheet to do it because of "post factory". Witch law prohibit that and talk about "post factory"?

So once again witch law prohibit somebody to remove the sponge from the topsheet, tune the sponge with any material if this material is still or become cellular rubber as described on the technical leaflet and handbook an re-glue on the topsheet witch is exactly as approved?

Thanks in advance!

Best regards,

Laurent Bérenger


Your question was very clear and my answer was very clear. "Additive" means to "ADD". Post factory this is illegal. At the factory, if the process of making the sponge follows the ITTF directives and the actual sponge leaves the factory free of VOCs, free of any poison, and the sponge itself will not alter the characteristics of any other component of the racket, and only the components as listed in 2.4 exist, then it would be OK. Anything else is not legal. This is very clear and according to our current rules. In fact, you should read "post-factory" as "post-production". This also applies to VOCs.

By the way, why are you corresponding with me in the Forum, I only come here occasionally. You can correspond directly with me at my private e-mail which you have and it is always my pleasure to answer you as I always do and also to meet you whenever possible. Please feel free to write to me directly.

Adham


Dear Adham

As suggested by speedplay, could we continue on this forum because a lot of players are concerned by this matter?

In fact my question was clear but you didn't answer... Additive on the factory step is legal because the sponge leaves the factory VOC free (so why advice aring the rubber for 72 hours??), free of poison (don't see any rule about it but I agree), and because the sponge itsel doesn't modify the top sheet and made by components listed on 2.4 (and because a rubber is any material with an minimum of elasticity, it is more difficult to break this law than follow it). OK! I get it!

But my question was: witch rule prohibits doing it post-production?? I really don't see it.. Please let me know witch chapter on the hanbook allows manufacturers to do it and prohibits it after the production step.

Also, topsheet can be sold alone. Witch rule prohibits to apply a cellular material boosted and VOC free??

Thanks in advance for your answer.

Best regards,

Laurent Bérenger[/quote]

Ok, I understand your question. The answer is rule 2.4. I actually answered this question already in detail in a previous post. I will just summarize here:

1. At factory level: The factory can do what it wants to produce the equipment, as long as when they are done, the equipment is according to ITTF rules. The production regulations are according to the rules for factories in that country. At the end of the production, and when ready to leave the factory, the equipment (in this case a racket covering) must be composed of only the elements and components that are listed in item 2.4 of the TT Laws. So if during the production VOC was used, as long as at the end of the production there is no more VOC, then it's OK. This applies to any other element during production. This is what we mean that it is OK during production, as long as when it leaves the factory it meets ITTF rules. This is why the ITTF makes tests on equipment we take from the general market. The glue (adhesive) is allowed according to our rule. We ask the factories to air the racket coverings after gluing the two parts together for at least 72 hours before packing. Some VOCs are still trapped, so we advise the players as well to air the racket covering before using to make absolutely sure that no VOCs are present.

2. At post-factory level (player, distributor, reseller, etc.): Any alteration (other than wear and tear) of the racket covering is illegal. Any additive (booster, tuner, oil, etc.) is illegal. This is Rule 2.4 (composition of the racket). Any action that alters the characteristics of the equipment after approval is illegal (rule 2.4.7).

These are the facts according to our current rule. If one day the rule is changed, then the process will also change. What is illegal today may become legal tomorrow and vice-versa.

I hope I have answered your question this time.

Adham

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PostPosted: 16 Dec 2008, 12:58 
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Hi Adham,

I'm sorry, I've been reading the story as it goes with Berenger and I still can't see where you have answered how that boosting a sponge on its own and then attaching a topsheet is illegal. I get that putting booster on a topsheet, or on a sponge with topsheet attached, is illegal. If the booster is VOC-free though, regardless of what its level of benefit to the sponge, where do the rules state this is illegal? I didn't think the ITTF ruled on sponges? I apologise if I'm missing something obvious here.

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RebornTTEvnglist wrote:
Hi Adham,

I'm sorry, I've been reading the story as it goes with Berenger and I still can't see where you have answered how that boosting a sponge on its own and then attaching a topsheet is illegal. I get that putting booster on a topsheet, or on a sponge with topsheet attached, is illegal. If the booster is VOC-free though, regardless of what its level of benefit to the sponge, where do the rules state this is illegal? I didn't think the ITTF ruled on sponges? I apologise if I'm missing something obvious here.


Rule 2.4 specifies the composition of a racket as follows:
2.4.2 The blade
2.4.3, 2.4.3.1, 2.4.3.2 The rubber, the sponge and the adhesive

Nothing else is allowed to be part of the racket other than what is indicated in Rule 2.4: the blade, the sponge, the rubber and the adhesive. Therefore any other item or component "added" to the above specifications is not allowed and is considered an "additive". So, to be more specific, boosting a sponge is actually applying an additive to the sponge. I do not see anywhere in Rule 2.4 this possibility. This is the current rule and the current interpretation.

Frankly, I do not see the advantage of boosting the sponge, then let it set, ensure that the surface is flat (assuming of course that it is VOC free) and then gluing it to a rubber. How will the boosted sponge provide the boosting effect unless it affects the rubber? which of course would then be illegal because it would alter the rubber. I just do not see the advantage of doing that.

Now, maybe the underlying question is "will it be detected?". Probably not if the racket surface is flat, the racket covering thickness is even over the entire racket surface and not more than 4mm, no dome effect, no stretching, etc., then will probably not be detected and also probably zero effect or advantage. So what is the purpose? Just to sell to a player a placebo effect?

In my opinion the manufacturers should spend their time and energy in producing ready made racket coverings, at reasonable prices, that the players can use and feel a similar effect as with the old speed-glue. This could be achieved with a clever balance and combination of new blades, new sponge, and new rubbers. Some manufacturers are already on the right track. It is just a matter of time, and more importantly, a matter of necessity.

Perhaps in the future the rule may change and non-toxic components may be added to the composition of the racket or part of the racket. I don't know? But I would not expect such a change any time soon. But I could be wrong.

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PostPosted: 16 Dec 2008, 14:16 
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adham wrote:
RebornTTEvnglist wrote:
Hi Adham,

I'm sorry, I've been reading the story as it goes with Berenger and I still can't see where you have answered how that boosting a sponge on its own and then attaching a topsheet is illegal. I get that putting booster on a topsheet, or on a sponge with topsheet attached, is illegal. If the booster is VOC-free though, regardless of what its level of benefit to the sponge, where do the rules state this is illegal? I didn't think the ITTF ruled on sponges? I apologise if I'm missing something obvious here.


Rule 2.4 specifies the composition of a racket as follows:
2.4.2 The blade
2.4.3, 2.4.3.1, 2.4.3.2 The rubber, the sponge and the adhesive

Nothing else is allowed to be part of the racket other than what is indicated in Rule 2.4: the blade, the sponge, the rubber and the adhesive. Therefore any other item or component "added" to the above specifications is not allowed and is considered an "additive". So, to be more specific, boosting a sponge is actually applying an additive to the sponge. I do not see anywhere in Rule 2.4 this possibility. This is the current rule and the current interpretation.

Frankly, I do not see the advantage of boosting the sponge, then let it set, ensure that the surface is flat (assuming of course that it is VOC free) and then gluing it to a rubber. How will the boosted sponge provide the boosting effect unless it affects the rubber? which of course would then be illegal because it would alter the rubber. I just do not see the advantage of doing that.

Now, maybe the underlying question is "will it be detected?". Probably not if the racket surface is flat, the racket covering thickness is even over the entire racket surface and not more than 4mm, no dome effect, no stretching, etc., then will probably not be detected and also probably zero effect or advantage. So what is the purpose? Just to sell to a player a placebo effect?

In my opinion the manufacturers should spend their time and energy in producing ready made racket coverings, at reasonable prices, that the players can use and feel a similar effect as with the old speed-glue. This could be achieved with a clever balance and combination of new blades, new sponge, and new rubbers. Some manufacturers are already on the right track. It is just a matter of time, and more importantly, a matter of necessity.

And the players should spend their time honing their techniques. The minimum amount of advantage the boosting of a sponge and then gluing it to the rubber, and if it does not alter the rubber in any way, this slight advantage if any, could be easily achieved by learning how to better accelerate the fore-arm, how to better use the stomach muscles, how to better transfer weight at the moment of impact, how to better use the wrist, etc., etc., etc.. And this would be "permanent" and of course "legal".

The coach in me resurfaces every once in a while. Sorry, if you already knew all that.

Adham

Perhaps in the future the rule may change and non-toxic components may be added to the composition of the racket or part of the racket. I don't know? But I would not expect such a change any time soon. But I could be wrong.

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 Post subject: Good stuff
PostPosted: 16 Dec 2008, 14:23 
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I really like this Forum and its a pleasure to be part of it. The Forum members here ask pertinent questions, intelligent questions and are genuinely interested to know. The debates are civil and honest. Good show you guys. And I have not been called any names, that is a relief.

I plan to stay in this Forum as long as needed, but sometimes due to personal business schedules, ITTF responsibilities and family circumstances, I may not be very quick at replying. I hope you all understand.

Thank you for making me feel comfortable here. By the way, I also like a German Forum on which I post as well. Also the members there are very genuine and interested in learning about the ITTF.

Adham

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adham wrote:
Glueless wrote:
adham wrote:
Glueless wrote:
adham wrote:
The problem in returning service is not so much the quantity of spin, the problem is to know the and recognize the amount and type of spin. If you can see the point of contact, and if you can see the direction of the toss, then it's rather easy to know the amount and type of spin. This is why I keep insisting about the "intent" of the rule. The main intent is "a clear view for the receiver", as long as that is achieved, then the players are happy. As long as they can see the point of contact then it's OK for them.


This would eliminate the need for the 'nearly vertical' portion of the rule. If I understand correctly, as long as I toss the ball at least 15cm in the vertical and do it so that the toss and contact point are perfectly visible to my opponent, then I have met the 'intent' of the rule and the angle at which I toss the ball is irrelevant.

I'm more confused now than ever. :oops:


Don't be confused. The necessity of the wording "nearly vertical" is to avoid one particular situation, whereas players where throwing the ball high, but to the side, and as the ball descended, they shielded it with the left shoulder (for right handed server). The ball was visible to the umpire all the time, but was shielded from the receiver just before the point of contact.


Adham,

Thank you for the kind response!

In my example I mentioned that the toss of my serve and contact point would be visible to the opponent. No shoulder in the way at all. No point of the toss or contact point is blocked from the opponent at any point during the service.

Would this service be legal regardless of the angle of my toss?


With all the conditions you mentioned, in ITTF events, the umpires do tolerate a toss that is about half way between the vertical and the horizontal, so nearer to 45% than 90%, so as long as your toss is not at the 180% level (0%), but nearer to 45% then it is currently tolerated. As I said in previous posts, this is at ITTF events and as long as the umpire does no see any unfair advantage being taken.

One very important point. I will never umpire any of your matches, so you have to accept the decision of the umpires that umpire your matches, right? Some are very strict and some are more lax. You have to serve according to the rule, and through experience you know the degree of tolerance accepted, but you can't throw the ball horizontally backward and claim that your service is legal because the point of contact is visible. here is my advice:
- Serve exactly as you described (all is clear to receiver) and stay within the 45% and 90% vertical.
- If you have a very strict umpire, then stay closer to the 90% vertical.
- Use common sense

But if I were you, I would spend more time on developing spin variations in my serves (using wrist, finger pressure, forearm acceleration, varying point of contacts, trunck rotation, etc.) - also see a previous post about this.

It is very difficult to explain this in writing, so I hope you get the gist of it.

Adham


Adham,

You did a fantastic job explaining this in writing, I think we all got the gist. This actually clears things up quite a bit! This is the first admission I have ever heard of the true tolerance levels allowed in legal services.

While I certainly understand that some umpires will interpret the rules differently, and therefore officiate their matches differently, I think this really helps to explain why we see such variation in services that are being allowed in officiated matches. The requirement of tossing the ball vertically is not treated as being terribly important in light of other more important aspects of the serve, like making sure that your opponent can see the service toss at all points of the service.

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PostPosted: 16 Dec 2008, 15:29 
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adham wrote:
I really like this Forum and its a pleasure to be part of it. The Forum members here ask pertinent questions, intelligent questions and are genuinely interested to know. The debates are civil and honest. Good show you guys. And I have not been called any names, that is a relief.

I plan to stay in this Forum as long as needed, but sometimes due to personal business schedules, ITTF responsibilities and family circumstances, I may not be very quick at replying. I hope you all understand.

Thank you for making me feel comfortable here. By the way, I also like a German Forum on which I post as well. Also the members there are very genuine and interested in learning about the ITTF.

Adham


Adham,

It is an honor to have you here Adham and I truly applaud your willingness to communicate so freely with those of us who are at the roots of this wonderful sport. Open communication between the grassroots players and the world organization can only increase understanding and solidify this sport at all levels of participation. I sincerely thank you for your efforts in initiating and maintaining that communication!

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