The table tennis rubbers can be categorized into two groups: pimpled and inverted. Pimpled rubber has many cylindrical "pips" protruding from the surface of the rubber, causing the striking surface to be uneven. Such rubber is best suited for defensive play where topspin is not as important. The pips come in two flavors, long and short. Short pips are thicker than they are tall, and are below 1 mm in height. Long pips tend to have an equal or greater length-to-width ratio. These special pips are designed to bend or 'kink' slightly upon impact with the ball, and produce many deceptive spins as a result. The legality of these long pips is currently under scrutiny, so caution is advised before making a purchase. In the modern table tennis game, the pimpled rubber is mainly used as a backup surface designed to add variety to one's game. Attacking players almost never use this as their primary surface.
On July 1, 1999, the following long pips rules were introduced:
* The aspect ratio, or height divided by diameter, will be the basis for legality
* 1.1 is the limit for aspect ratio; anything higher is illegal
* The unpredictable 'kinking' of the pips has been cited as the reason for the passage of this amendment
The inverted, or 'smooth' rubber, is actually a sheet of pimpled rubber turned upside down so that the flat surface under the pimpled side becomes exposed. Nearly all inverted rubber has a layer of sponge sandwiched underneath. The sponge adds speed and/or control to the rubber, depending on the thickness and composition. Inverted rubber makes possible a greater variety of spin shots and attacking games requiring heavy topspin and other spin-intensive strokes. The surfaces of many inverted rubbers are 'sticky', allowing a player to gain the traction needed to produce spin. Most beginners should start with inverted as their primary rubber, for the sake of learning today's most effective techniques.
Regulations require rubber to be either red or black, and one of each color must be placed on a paddle for it to be legal(penhold paddles with only one rubbered side must make the other side red or black, depending on the color of the rubber). Be sure to realize this and request the appropriate colors. Also, be sure that the rubber itself is no thicker than 2 mm and the combination of rubber and sponge no thicker than 4 mm. The majority of retailers sell legal rubber so this shouldn't be too much of a problem.
Rubber has a rating system that measures speed and spin independently. There are no standard notations, but many companies that distribute rubber rate speed and spin on a 1 to 10 scale, with 10 being the most spinny or quick. The ratings are usually determined by players who evaluate them specially to analyze the speed and spin. You can also ask around about a particular brand of rubber or try it out yourself. One can test out blades this way also. Remember that the ratings will most likely be 'opinions' and not machine-tested. Take ratings with a grain of salt, and simply realize that getting an exact kind of rubber will not be the most important thing until you are at a level of play to do so.(Note: Beginners should not select overly spinny rubbers, because while these rubbers will allow the production of better spin, they will also be more affected by the spin that their opponents impart on the ball. When the 'touch' is not yet mastered, it is very difficult to return a spinny shot on sticky rubber.)
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by cleamaes Tue Jan 31, 2012 4:20 pm
Subject: Wozniacki Plans To Apply To Yale University 
