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Relation between speed, throw, arc, catapult, hardness, flex
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Author:  Pipsy [ 11 Mar 2015, 21:57 ]
Post subject:  Relation between speed, throw, arc, catapult, hardness, flex

I’m trying to understand but I hear different explanations, so please enlighten me…

Are throw and arc the same concepts pointing to the flatness (or curvedness) of the ball trajectory?

Do faster blades by definition mean a flatter trajectory (lower throw)?

How does wood hardness play a role in trajectory. I’d assume lower throw because it’s faster?

Does flex mean higher catapult and less linearity? Making throw higher? Or is catapult basically the same as speed?

Thanks!

Author:  dunc [ 11 Mar 2015, 22:12 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

Oh Lord you're opening a can of worms here :lol:

I would define "throw" as the height that the (rubber/blade) gives the ball on a standard loop.

I would define "arc" as the shape of the path of travel that the ball takes.

You could realistically use arc/throw interchangeably though.

I would define "catapult" as something slightly different to "speed". To me, "catapult" is the rebound effect that the (rubber/blade) has on the ball. For example, Calibra LT Sound on a TSP 3.5 Balsa blade will "ping" the ball forward with very little effort. That has a HIGH catapult effect.

On the other hand "speed" or "power" would be defined by how quickly the (rubber/blade) plays certain strokes, i.e. the powerloop. I think weight has an important part to play in this. The aforementioned Calibra/Balsa combo won't give you real power on a powerloop.

Author:  Pipsy [ 11 Mar 2015, 22:22 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

Thanks Dunc! That all sounds reasonable...

I'm especially interested in how these phenomena are related to blade characteristics. You mentioned weight, but there's also wood hardness, flex, thickness, size, plies...

dunc wrote:
Oh Lord you're opening a can of worms here :lol:

I would define "throw" as the height that the (rubber/blade) gives the ball on a standard loop.

I would define "arc" as the shape of the path of travel that the ball takes.

You could realistically use arc/throw interchangeably though.

I would define "catapult" as something slightly different to "speed". To me, "catapult" is the rebound effect that the (rubber/blade) has on the ball. For example, Calibra LT Sound on a TSP 3.5 Balsa blade will "ping" the ball forward with very little effort. That has a HIGH catapult effect.

On the other hand "speed" or "power" would be defined by how quickly the (rubber/blade) plays certain strokes, i.e. the powerloop. I think weight has an important part to play in this. The aforementioned Calibra/Balsa combo won't give you real power on a powerloop.

Author:  iskandar taib [ 13 Mar 2015, 15:52 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

Oh boy. Go look through the last years' worth of posts, you'll find lots of discussion and very little light shed.

One thing I'm pretty sure DOESN'T happen is the blade flexing along it's length. Even the thin blades are just too stiff given the weight of the ball we play with.

Iskandar

Author:  Pipsy [ 13 Mar 2015, 19:50 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

What I remember from those this discussions is that it was about whether a blade flexes or not. This is not my question. I think most of us know what is meant by a stiff versus a flexible feeling. I'd like to have some more insight into the relation between especially ball trajectory and blade characteristics (and maybe this is hard to tell without also discussing the kind of rubber on a particular kind of blade)

iskandar taib wrote:
Oh boy. Go look through the last years' worth of posts, you'll find lots of discussion and very little light shed.

One thing I'm pretty sure DOESN'T happen is the blade flexing along it's length. Even the thin blades are just too stiff given the weight of the ball we play with.

Iskandar

Author:  chicane [ 23 May 2015, 04:41 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

It's complicated because there are so many variables and you cannot fully freeze all and play with only 1 at any time. That's why it's so hard to make the perfect blade.

I am told (by people w/ several years selling & playing w/ blades) to consider the speed & feel alone when it comes to the blade and ignore the spin/control/arc aspect. With all the other attributes being more influenced by the rubber and less by the blade.

The catapult/flex vs. speed story has to do with the speed & acceleration of your wrist. Theoretically, the bigger & faster your swing, the better off you are with a flexy/catapulting blade ie less power. Unlike tennis, the masses are negligible so stiffness dominates. It doesn't mean you cannot feel a blade flex but you ought to be hypersensitive to the feedback you get from your blade as everything here is in milliseconds. Higher catapult does not mean higher throw, it does have a higher potential of altering the throw however. Think of hitting against a brick wall vs hitting against one of those practice springy nets. There is no room of wiggle against the hardness of a wall, so the ball collides and returns with the same initial energy resulting in the same speed of the incoming stroke with minimal loss. Now if you make the wall move fwd to collide with the ball then your speed will be faster. As to catapult effect, the variation is that the ball takes longer to lose its incoming energy as it's sinking into flexing surface. the higher the resistance of the catapulting surface the more powerful it will be. Think of a very hard bow that takes more energy to bend but launches the arrow so much faster w/ a higher acceleration, vs a bow with lower resistance, that is easier to bend but shoots w/ less power. the last point to clarify is that the more flexible (lesser resistance) the blade the longer dwell you have. As no one has 100% linear stroke, any minor variation has higher chance of adding angular and/or frictional force on the ball thus potentially creating a higher arc.

The arc/throw angle in a blade are a function of the material fibers, the angle at which they flex and the issuing friction with the ball. You could semi ignore this because this effect is masked by the greater one generated by the rubber. And yes, they are the same thing as you defined them. Just keep in mind that the fibers (type of wood or material) influence the arc as 2 blades of the same hardness may throw the ball differently.

It's good to try and understand this, but it's best not to dwell so much on it. Trial and error, and scraps of information are the way to go...especially that the human hand and nervous circuit can tweak most of it intuitively.

Author:  Kees [ 07 Jul 2015, 03:46 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

In my opinion many of the terms (catapult, flex, throw, arc, speed) are used in different ways by different persons. It would make sense to use them in just one way, that is according to the definition they have in the natural sciences.

Catapult is acceleration, i.e. the phenomenon that a force when exerted on an object will increase or decrease its speed. Speed is the result of the exertion of force.

Flex is the force exerted by a blade that regains its overall shape, reacting to the deformation which is due to the impact of the ball. As a rule, a blade consisting of less and/or thinner plies will have more flex; but the woods used are a separate factor in this. A blade consisting of more and/or thicker plies will have less flex. Especially blades with a thick core will have little flex.

Spring is the force exerted by a blade when one or more of its plies react to the (local) compression which is due to the impact of the ball. Note the difference with flex, which isn’t due to local deformation, but overall deformation. Of course, the influence on the ball is the same, viz. increase or decrease of its speed. Spring depends on the consistency of the woods used. Balsa has a lot of spring, as a rule; hinoki as well; willow has little spring. There is little or no relation between spring and the number of plies used; but the thickness of the plies is a factor – generally the thicker, the more spring.

Throw refers to the angle with which an incoming ball with zero spin bounces off.
A blade that tends to deform as a whole (flex) on impact will have a high throw, as it bends backwards, thus increasing the angle.
A blade that tends to be compressed locally (spring) on impact will have a low throw, as it doesn’t bend and thus the angle isn’t increased.

In contrast to throw, arc is the curvature of the complete trajectory of the ball leaving the blade until it contacts the table. The curvature can be high (short and domed trajectory) or low (long and flat trajectory).
A blade with flex tends to have high arc, due to its high throw. A blade with spring tends to have a low arc, due to its low throw. Still, a fast blade will generally produce a lower arc than a slow blade.

A blade with low speed can nevertheless have high catapult. This will be the case when it is relatively thin and therefore has high flex. This kind of slow defensive blades will produce “unexpected” speed with a good swing and therefore will loop just fine for counter-attack away from the table.

A blade with high speed will nearly always have high catapult – without it, it wouldn’t be able to generate that speed. But there is one exception: a very heavy blade will be able to produce high speed even when it is relatively slow, not flexy and not springy, and has little catapult. This is because here momentum is of more importance than acceleration. Heavy blades with low catapult tend to excel in control, which may explain why they are popular in Asia.

Author:  Kees [ 07 Jul 2015, 04:38 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

The above is not meant to imply that the relations between the terms defined there are as straightforward... For instance, the Tibhar Defence Plus is a 5 ply blade, consisting of 3 thin ayous (I think) layers with 2 thin balsa layers in between them. As a result, the blade has relatively high flex (but not as high as it would be without the balsa plies) and has relatively high spring as well (but not as high as when the 2 balsa plies would have been 1 core ply of their total thickness), together with a rather low basic speed. The combination of spring and flex makes it unexpectedly fast with good swings or on high impact, and since there are (at least) two factors contributing to its catapult, it is rather hard to control (for a defensive blade), but only when you want to make high speed - balls will tend to go long, even when the curvature is moderate. But a player can learn to adjust; also, soft and tacky rubbers with low catapult and moderate speed will compensate the lack of control. And of course the blade was designed to be like this, hence the "plus" after "defence".

Author:  so_devo [ 07 Jul 2015, 17:32 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

Pipsy wrote:
I’m trying to understand but I hear different explanations, so please enlighten me…

Are throw and arc the same concepts pointing to the flatness (or curvedness) of the ball trajectory?

Do faster blades by definition mean a flatter trajectory (lower throw)?

How does wood hardness play a role in trajectory. I’d assume lower throw because it’s faster?

Does flex mean higher catapult and less linearity? Making throw higher? Or is catapult basically the same as speed?

Thanks!

My 2 pence worth.......

Throw is the initial angle that a given stroke will produce. So for example, with the same fh drive stroke the ball will come off a rakza 7 setup higher than a rakza 9 setup. Neither is better or worse, it is about what you prefer and strokes can be adjusted. I also find that high throw rubbers tend to be both spinnier and more sensitive to spin. Rubbers with larger pimples, either in or out, tend to be lower throw. I am sure there are lots more variables too.

For me arc is the shape, or 'dip' that a loop can achieve, so very closely related to how much topspin a rubber can generate balanced with its speed....the quicker it is the less opportunity the ball has to dip. Arc is a good thing!

Catapult is, to me, the opposite of linearity. The 'free' speed that you get from a fast, modern and nearly always softer rubber or certain blades. Linear setups have more control and better touch but you have to work harder for the speed. Often this means harder rubbers with higher top end speeds.

Blades are greatly affected by construction and materials. The modern composites are stiff and often quick, all wood blades tend to be flexier. Less plies tend to be flexier. But these are generalisations. Rule of thumb is stiffer for close to the table and flexier at distance.

Author:  haggisv [ 07 Jul 2015, 17:41 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

so_devo wrote:
Throw is the initial angle that a given stroke will produce. So for example, with the same fh drive stroke the ball will come off a rakza 7 setup higher than a rakza 9 setup. Neither is better or worse, it is about what you prefer and strokes can be adjusted. I also find that high throw rubbers tend to be both spinnier and more sensitive to spin. Rubbers with larger pimples, either in or out, tend to be lower throw. I am sure there are lots more variables too.

For me arc is the shape, or 'dip' that a loop can achieve, so very closely related to how much topspin a rubber can generate balanced with its speed....the quicker it is the less opportunity the ball has to dip. Arc is a good thing!

Catapult is, to me, the opposite of linearity. The 'free' speed that you get from a fast, modern and nearly always softer rubber or certain blades. Linear setups have more control and better touch but you have to work harder for the speed. Often this means harder rubbers with higher top end speeds.

Blades are greatly affected by construction and materials. The modern composites are stiff and often quick, all wood blades tend to be flexier. Less plies tend to be flexier. But these are generalisations. Rule of thumb is stiffer for close to the table and flexier at distance.

That's exactly how I see it as well... agreed with all your points! :up: :up: :up:

Author:  Pipsy [ 08 Jul 2015, 20:33 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

Very enlightening, thank you Kees!

Kees wrote:
In my opinion many of the terms (catapult, flex, throw, arc, speed) are used in different ways by different persons. It would make sense to use them in just one way, that is according to the definition they have in the natural sciences.

Catapult is acceleration, i.e. the phenomenon that a force when exerted on an object will increase or decrease its speed. Speed is the result of the exertion of force.

Flex is the force exerted by a blade that regains its overall shape, reacting to the deformation which is due to the impact of the ball. As a rule, a blade consisting of less and/or thinner plies will have more flex; but the woods used are a separate factor in this. A blade consisting of more and/or thicker plies will have less flex. Especially blades with a thick core will have little flex.

Spring is the force exerted by a blade when one or more of its plies react to the (local) compression which is due to the impact of the ball. Note the difference with flex, which isn’t due to local deformation, but overall deformation. Of course, the influence on the ball is the same, viz. increase or decrease of its speed. Spring depends on the consistency of the woods used. Balsa has a lot of spring, as a rule; hinoki as well; willow has little spring. There is little or no relation between spring and the number of plies used; but the thickness of the plies is a factor – generally the thicker, the more spring.

Throw refers to the angle with which an incoming ball with zero spin bounces off.
A blade that tends to deform as a whole (flex) on impact will have a high throw, as it bends backwards, thus increasing the angle.
A blade that tends to be compressed locally (spring) on impact will have a low throw, as it doesn’t bend and thus the angle isn’t increased.

In contrast to throw, arc is the curvature of the complete trajectory of the ball leaving the blade until it contacts the table. The curvature can be high (short and domed trajectory) or low (long and flat trajectory).
A blade with flex tends to have high arc, due to its high throw. A blade with spring tends to have a low arc, due to its low throw. Still, a fast blade will generally produce a lower arc than a slow blade.

A blade with low speed can nevertheless have high catapult. This will be the case when it is relatively thin and therefore has high flex. This kind of slow defensive blades will produce “unexpected” speed with a good swing and therefore will loop just fine for counter-attack away from the table.

A blade with high speed will nearly always have high catapult – without it, it wouldn’t be able to generate that speed. But there is one exception: a very heavy blade will be able to produce high speed even when it is relatively slow, not flexy and not springy, and has little catapult. This is because here momentum is of more importance than acceleration. Heavy blades with low catapult tend to excel in control, which may explain why they are popular in Asia.

Author:  haggisv [ 08 Jul 2015, 20:45 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

Yes, great post Kees! :clap: :clap: :clap:

There is so much great information in this thread, that gets asked over and over again, that I've stickied this post, so next time we can point them to this thread (if we remember about it :oops: ).

Author:  Zhaoyang [ 09 Jul 2015, 01:30 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

I'm surprised that the original poster is Pipsy, who does not need advice from me, but this post is for most people interested in this kind of thread:

It's terribly unfortunate that a community like this can't develop a glossary to help us reason together better. Since that isn't going to happen (and we wouldn't want to try to force people to stick to it anyway, right?), I'll mention again a very good alternative: find a player who plays the way you wish to play (keeping in mind that wishing is not enough, so if you aim higher you'll need more coaching and practice), and whose equipment you can identify with reasonable-enough certainty, and just use what they use. Then watch their videos and train to hit as they do. They'll show you the useable performance "envelope" of that equipment; no motley crew of equipment reviewers should be trusted above that.
Compared to the neck-deep chaos and nonsense we must wade through and sort through, of rubber and blade reviews, the chosen player shows us what a rubber and blade can do; we skip the verbiage, choose the player, and then practice equipment-worry free.

What about my own preferences? I have a right to them but it costs me. For example, I continuously itch for a spinnier rubber than my model player uses. If I change, then the outlines of the corresponding game would change, and this is how it would happen if I followed the above principle: I would not shop for a spinnier rubber. Instead, I would shop for a new model player whose game demands a spinnier rubber, and whose equipment I can identify with reasonably-enough certainty, and use whatever the new model uses, and train to play accordingly. The trouble is, my current model plays a game that I can emulate a little and reasonably aspire to, so if I change it would probably be to something more physically demanding (as I already know of players who play similarly but with spinnier rubbers). So I must weigh the cost of that first, and not just salivate over equipment ratings written by people like us. Well, whatever that means I did include myself.

Good luck.

Author:  Lhet [ 26 Aug 2015, 15:07 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

Uh. I'll post too because I slightly disagree.


Throw is something you can feel, and is almost all in the rubber. If you try somebody else's setup and find you really have to close your bat angle to land it on the table, then it's higher throw. This is probably somehow proportional to the sideways deformation and rebound of the rubber: If the rubber absorbs spin by deforming sideways and the ball leaves before it rebounds, then you have a somewhat spin killing rubber with low throw. If the rubber absorbs spin and almost immediately rebounds while the ball is still on it, then you have a super spinny rubber with high throw. The blade can matter a bit, but the term is most useful for comparing rubbers.

Catapult is mostly in the sponge. It's probably some sort of relationship between how soft the rubber is and how much energy it returns (which can by measured by dropping a ball and seeing how many times it bounces). It's basically how much more power there is in a returned shot vs. a shot that you hit out of your hand. Even though this is largely in the sponge, a soft, stiff blade (e.g. Hinoki) can also add to this.

Author:  iskandar taib [ 27 Aug 2015, 01:22 ]
Post subject:  Re: Relation between speed, throw, arc, catapult, hardness,

Zhaoyang wrote:
I'm surprised that the original poster is Pipsy, who does not need advice from me, but this post is for most people interested in this kind of thread:

It's terribly unfortunate that a community like this can't develop a glossary to help us reason together better. Since that isn't going to happen (and we wouldn't want to try to force people to stick to it anyway, right?), I'll mention again a very good alternative: find a player who plays the way you wish to play (keeping in mind that wishing is not enough, so if you aim higher you'll need more coaching and practice), and whose equipment you can identify with reasonable-enough certainty, and just use what they use. Then watch their videos and train to hit as they do. They'll show you the useable performance "envelope" of that equipment; no motley crew of equipment reviewers should be trusted above that.
Compared to the neck-deep chaos and nonsense we must wade through and sort through, of rubber and blade reviews, the chosen player shows us what a rubber and blade can do; we skip the verbiage, choose the player, and then practice equipment-worry free.

What about my own preferences? I have a right to them but it costs me. For example, I continuously itch for a spinnier rubber than my model player uses. If I change, then the outlines of the corresponding game would change, and this is how it would happen if I followed the above principle: I would not shop for a spinnier rubber. Instead, I would shop for a new model player whose game demands a spinnier rubber, and whose equipment I can identify with reasonably-enough certainty, and use whatever the new model uses, and train to play accordingly. The trouble is, my current model plays a game that I can emulate a little and reasonably aspire to, so if I change it would probably be to something more physically demanding (as I already know of players who play similarly but with spinnier rubbers). So I must weigh the cost of that first, and not just salivate over equipment ratings written by people like us. Well, whatever that means I did include myself.

Good luck.


The main problem with this approach is you might not have the ability to use the equipment your model player uses, at least, not to the same effectiveness, and it might be better to get something a little slower or more controllable. There are probably a lot of people who WANT to play like Ovtcharov, but for whom a fast carbon blade isn't ideal.

Iskandar

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