Question about stretching rubber on blade

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I've heard some people recommend pulling the rubber to stretch it out as you glue it onto the blade. I do this occasionally when the rubber isn't long enough and I try to cover the length of the blade.

Does this stretching make the rubber bouncier/faster?
 
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According to my experience everytime I stretch a rubber it shrinks after removing, so if the rubber has been stretched I keep it on the same blade till it dies. I would stretch a bit all the soft rubbers I use , but not the hard ones
 
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Yes it does
Where is your proof? There are no equations for tension making a rubber spinnier.

but it can also make it inconsistent as you might not be able to stretch it consistently over the whole surface.
If the rubber is stretched before applying to the blade then the stretch will be consistent. Stretching the rubber AFTER part of the rubber attaches to the blade will result in inconsistent tension.

It can also cause the edge of the rubber to come loose, as the tension pulls in the rubber from the edge.


Yes! And if you need to reattach the rubber it will not fit the blade unless you stretch the rubber again.

There is NO equation for spin as a function of tension. I have asked many times for someone to provide one. I know it doesn't exist.
 
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Boosting will ‘stretch’ the sheet in a more consistent manner, in both directions, top to bottom and left to right., the whole sheet should increase in size by 2 to 3 mm across width and length.
Some rubbers may respond better or worse than the sheets I measured over the boosting process, so exactly how much of an increase in size there is, can only be determined by actually measuring the sheets during boosting.
My measurements were taken whilst the sheets were domed

How stretching the sheet along one axis only affects the overall performance, I don’t know. Will it be faster / bouncier? It should be,
if the ‘stretch’ caused by boosting causes more bounce and some extra speed then so should stretching the sheet across 1 axis.
 
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Show us proof that stretching the rubber makes it "bouncier/faster".
Imagine a trampoline that was stretched very tight so that when you jump on it, it barely depresses.

Imagine a trampoline that isn't stretched optimally so that you jump on it you barely bounce.
Show us proof that stretching the rubber doesn't make it "bouncier/faster".
 
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Imagine a trampoline that isn't stretched optimally so that you jump on it you barely bounce.
Show us proof that stretching the rubber doesn't make it "bouncier/faster".


In the case of a trampoline the springs should be adjusted for the weight of the jumper although that rarely happens.
If the jumper can't depress the trampoline there will be no return spring. Obviously if the springs are too soft the trampoline will just sag. There is a happy "Goldilocks" zone.
However, the weight of TT balls doesn't change.
It is up to those making the assertion to prove it.
 
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In the case of a trampoline the springs should be adjusted for the weight of the jumper although that rarely happens.
If the jumper can't depress the trampoline there will be no return spring. Obviously if the springs are too soft the trampoline will just sag. There is a happy "Goldilocks" zone.
However, the weight of TT balls doesn't change.
It is up to those making the assertion to prove it.

... and if the trampoline is tightened it will become harder and faster bounce.

 
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... and if the trampoline is tightened it will become harder and faster bounce.

I agree the trampoline will seem "harder"
But is that what you want? How hard is too hard? In the case of the trampoline there is too hard and too soft.
Engineers think in term of forces and energy. How does stretching the rubber add more energy to the rebound?
If I stretch the rubber even more will it return even more energy? What if I stretch the rubber even more? The ball can't leave with more than more energy than what it had at first contact.

Show me an equation the shows stretching the rubber increase rebound speed or COR.

Yes, USDC, I am trolling. I know these guys can't prove anything.
 
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Just because it is not proven by any phycisist, doesnt mean it is not true. If there is any equation that might disprove it you can enlighten us and write an essay about it.

Besides that you already kind of proved it yourself just by agreeing that it is possible through your dumb teampoline hypothesis.

Btw a simple Wiki article should help you at least a little bit: https://en.m.wikipedia.org/wiki/Speed_glue
 
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imo, people are using the term "fast" in very different ways. Fast can mean the ball speed itself, i.e. the velocity of the ball after leaving the rubber surface. It can also mean the time the ball makes contact with the rubber, i.e. short contact time equals fast, or dwell time if you would prefer the term. So, in terms of fast in the "contact time" aspect, I think stretching makes the rubber "faster", since stretching -> harder surface -> less contact time. But whether the ball travels faster is a whole other story, and I don't have an concrete answer to that, but my instinct from my years of taking engineering courses in college and grad school tells me that it depends... on a whole lot of variables.

The spring equation is F=-k*x, where k is the spring constant or coefficient, which basically is the stiffness of the spring if the material isn't changed, and x is the distance the spring is compressed. So if you use the same exact stroke (F is kept the same) to play a rubber that's harder, it means the rubber will compress less (k increases, so x decreases). And the spring potential energy is dictated by these as well P.E.=F*x, so with less compression comes less potential energy, and when that energy is turned into kinetic energy, it meaning the ball will travel at a lower speed K.E.=(1/2)*m*v^2.

This is however, not the same as saying harder rubbers (whether by design or stretched) results in lower speed. The ball will only travel at lower speeds when the stroke is exactly the same as before, but with harder rubber you can apply more force to the ball without bottoming out the rubber. And when more force is applied you can still achieve the same compression on the harder rubber, so the energy store will be higher. This is to say that the potential of the potential energy is higher with harder rubbers, or in plain English, the speed ceiling is higher on harder rubbers.

That's the rubber part, now we also have the relationship among force, speed, mass and time, F = m*(v/t) , which if you adjust the sides a bit becomes F/m*t=v, which basically is saying if the force (stroke) and mass (ball) is kept the same, when the force has less time to work on the ball, it means the ball will travel at lower speeds, duh. All of this makes sense if you remember that, tacky Chinese rubbers are hard, because harder means less contact time, where the tackiness comes in to increase contact time.

Phew, so rusty on these stuff, haven't touched any of these in years lol
 
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I agree the trampoline will seem "harder"
But is that what you want? How hard is too hard? In the case of the trampoline there is too hard and too soft.
Engineers think in term of forces and energy. How does stretching the rubber add more energy to the rebound?
If I stretch the rubber even more will it return even more energy? What if I stretch the rubber even more? The ball can't leave with more than more energy than what it had at first contact.

Show me an equation the shows stretching the rubber increase rebound speed or COR.

Yes, USDC, I am trolling. I know these guys can't prove anything.
Show me an equation that shows that stretching the rubber decreases rebound speed.
You can't. There is no such equation.

As I stated elsewhere:
Until someone makes a tests and measurements with a machine I will believe one of the worlds best players who trains hours per day and is very sensitive to slightest changes to his equipment. After all these players weight and pick their rubbers, every tiny bit of performance is important to them.
Therefore stretching a certain rubbers while gluing makes them harder and faster.

Are rubbers made to be stretched mechanically? Probably not but they have some leeway so that you can do it without ruining their properties.
 
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Show me an equation that shows that stretching the rubber decreases rebound speed.
You can't. There is no such equation.

As I stated elsewhere:
Until someone makes a tests and measurements with a machine I will believe one of the worlds best players who trains hours per day and is very sensitive to slightest changes to his equipment. After all these players weight and pick their rubbers, every tiny bit of performance is important to them.
Therefore stretching a certain rubbers while gluing makes them harder and faster.

Are rubbers made to be stretched mechanically? Probably not but they have some leeway so that you can do it without ruining their properties.

lol I guess you just completely ignored my post there

 
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Nice. Yeah, I doubt that top professional players would be mistaken about something like this.

Do the CNT players do this also?
 
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