OOAK Table Tennis Forum

This is not a simple question taken in its entirely. The same blade w/o another layer to further reduce elasticity will most assured be faster (ie more rebound) in the direct perpendicular to the face. However given such a thing has zero grip it will be up to -infinitely slower as that angle changes.

It's also best to take LP out of the equation since their behavior is complex. For example soft reversal pip are often not slow on direct face impact ("hard to control" for hits), but even a seemingly straightforward vertical block will bend the pips and significantly reduce speed due to the slight angle ball comes up from.



I'm not doubting your recollection of his story, however Reismann was prone to flights of fancy so it'll forever remain a mystery whether he actually believed it or it's another one of his tall tales about sponge's evil magic.

It also doesn't take a drive to return the ball faster. Against an offensive shot with some topspin, a grippy bat will naturally return some top esp with a bit of a counter(hit).

The thin sponge = slow vs. thick sponge = fast thing doesn't only apply to long pips, thin-sponged inverted is slower than max-sponged inverted. And this applies to backspin (pushes and chops) as much as it applies to topspin shots so the added-possible-speed-because-of-added-possible-topspin argument doesn't work.

The Rasant people seem to believe that the sponge can recover fast enough to act as a spring:



When you assert it doesn't, what evidence do you have? You do believe the ball can act as a spring, why not sponge?

Anyhow this is straying far from the topic at hand.

Iskandar

Everything here acts as a spring, but the spring rate/frequency of the ball is faster (ie along the arrow of time) so it completes its cycle before the others. The analogy I used before of the jumping on a trampoline is insightful here: to get max height (what can be accurate called "catapult" in some sense) you must pump your legs at the exact natural frequency of the contraption. However the ball has no such capability, and does the equivalent of pumping your legs too fast and gets no such mechanical assistance.

It's possible to estimate the frequency by just listening to the pitch of collisions; rubbers have nowhere near the pitch of the ~1khz ball. The cycle length in time is 1/frequency (technically 1/(2*freq) here) by definition.


> The thin sponge = slow vs. thick sponge = fast thing doesn't only apply to long pips,

It applies to anything. However, the useful property of LPs is off-axis when other properties like bending of the pips dominate. That's also true for sponged inverted, but the reason anyone bothers with LPs is their behavior drops off a cliff.

> thin-sponged inverted is slower than max-sponged inverted.

It's not though, and again this is easy to test if you had a thin and thick sponge of the material to bounce the ball off of. If you don't, imagine what happens when that sponge thickness on a wood backing approaches zero.

The trampoline model is again instructive here. You can still jump reasonably high on a tight trampoline with completely off-speed timing, but a trampoline with more play will be less effective for this since it absorbs your kick more.

> And this applies to backspin (pushes and chops) as much as it applies to topspin shots so the added-possible-speed-because-of-added-possible-topspin argument doesn't work.

It's harder to compare shots at an angle because they're not necessarily at the same angle between two rubbers. The whole point of adding sponge is so more angled spin shots are feasible. Try looping with a hardbat. A more fwd angle of attack for example would have more advantageous geometry (larger component going fwd instead of up), though the greater factor is still going to be more spins allows faster contact speed.

I am too late to find this pdf url。This web page is 404 now. Could anyone send this http://www.ittf.com/museum/TTC75.pdf file to my email : [email protected] . Thanks a lot !!!

Also late here, but I found this about the 1952 WC.

http://ttnzarchives.org.nz/chronicle/1952.htm

Which contains the following "Unlike Nishimura, Satoh fully exploited the properties of sponge by variously counter-hitting, floating, chopping, blocking and suddenly springing into attack – deceiving and wrong-footing opponents every inch of the way." Seems to contradict received wisdom about Satoh's playing.

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Other setups:
SDC Custom Blade/Butterfly Dignics 80/Butterfly Glayzer
BTY Viscaria/Tibhar K3/Tibhar K3

https://www.ittf.com/wp-content/uploads ... /TTC75.pdf

This is seemingly the doc source you aspire for.