OOAK Table Tennis Forum

Seems to be a trend with the more modern (more spinny) short pimples having softer sponge compared to modern inverted rubbers. I’m curious as to why the trend seems to be almost exclusively in the direction of softer sponges which – to me – seem to lack power compared to the much firmer sponges used on modern inverted rubber. Modern inverted rubber, meanwhile, seems to be going in the opposite direction with harder and harder sponges being produced. Is there a reason for this? Just as an example the Butterfly Impartial XS is a modern spinny SP…but it uses a soft sponge compared to the likes of the tenergy or dignics sponges. I think I’m right in saying that even the tenergy FX sponges are firmer than the standard sponge of the Impartial XS. Is there a reason why the sponge technology used in the modern inverted rubbers doesn’t ever seem to be used for modern SP's? Why no butterfly short pimples with a tenergy sponge?

One reason will be that inorder to enable topspin counter hits and loops from a short pip rubber to replace inverted on the forehand, the ball needs to sink into the sponge, so a soft tensor sponge thus gives both speed and grip. Also a softer sponge short pip apparently makes it easier to block heavy topspin.

A harder sponge short pip is more of a classic hitting rubber.

Softer sponges on SPs makes flat hitting easier/more forgiving. The Softer base allows some degree of pips bending making them less "sensitive" to spin and give slightly more margin for wrong angle.

I don't agree with the idea of sinking into the sponge to create spin. A grippy topsheet+hard sponge is capable of much higher spin potential than the same topsheet on a soft sponge.

I see benefits for both types, but as skills improve, harder sponge SPs have more potential. Less "spring/bounciness" on low impact, but much higher smashing power.

Try the 42 degree 802-40 or Dolphin if you like harder feel. They don't bottom out as easily and smash faster than tensor pips, but you have to commit to get the speed out of them.

For inverted, the ball contacts a lot of topsheet, there is a relatively large amount of friction. A harder sponge does have the potential of making more spin (as long as you can supply the racket head speed). You also get added spin when the pips sink into the sponge and the whole of it deforms and springs back (there's that Rasant video on YouTube that shows this). For pips out, though, the surface area in contact with the ball is much less, there will be more slippage. You also don't get pips digging into the sponge, you instead get the flat surface of the topsheet pressing onto the sponge, over a much greater surface area. So perhaps a softer sponge would work better, if it allows the ball to "sink" further into the rubber and allow contact with more of the pips.

Iskandar

Some SPs have different sponges and in most cases harder sponges lead to more speed, less spin, worse control.
I think many modern inverted rubbers are faster then any popular SP rubber.

If you read old books (from the 1960s/70s) they'll explain that pips out would give you more speed, inverted would give more spin. And it might well have been true back then, with "normal" topspin drives. These days, with the fast loop, the more spin you put on the ball the more speed you can put on the ball and still have it hit the table. So inverted has more potential speed if you use the right strokes.

Iskandar

With topspin balls yes. But when putting all your effort forward in a smash, you can get much higher speed even if modern short pips are not as fast as inverted. And smashing with shorts pips are intrinsically easier then with inverted.

Flat hitting is not obsolete!

Would a thicker soft sponge help to return heavy loops? Since has more cushion and energy is lost in the sponge

I don't think energy is lost in the sponge...Thicker sponge will also make it less precise, maybe harder to return heavy loops.