Topsheets
The topsheet of a rubber is the surface which sits on top of the sponge (assuming sponge is used), or directly on the blade (if sponge is not used), and which makes contact with the ball. Like sponge, there are several factors to consider when choosing topsheets for your table tennis rubber.Pimples-In (smooth) or Pimples-Out?
Most new table tennis players who are looking to take the sport seriously are told to begin with pimples-in rubber. The reason for this is that it will allow them to develop all the strokes used in table tennis while they are learning the game. Once they have developed a style of their own, the players can then decide whether to stick with normal rubbers, or whether to choose an anti-spin or pimples-out rubber that would be better suited for their particular style of play. It is relatively rare these days for new players to begin with pimpled-out rubbers.
Tackiness
The tackiness of the topsheet is a measure of how much it grips the ball when the ball is struck. Some rubbers, such as Neos Tacky or Friendship 729, grip the ball a lot - it is difficult to slide a ball across the surface. Other rubbers, such as Bryce, Sriver, or Mark V, will allow a ball to be slid across the surface much more easily. And of course, their are the anti-spin rubbers, which will offer virtually no resistance when a ball is pushed across the surface.
In general, tacky rubbers are able to place more spin on the ball, but suffer from the problem of being more affected by the opponent's spin as well. Traditionally (say up to about the late 1980's), the Chinese players used to use tacky rubbers and hard sponge without speed glue, while Europeans speedglued their bats and used less tacky rubbers and softer sponge.
In today's modern game though, almost all the professionals are using speed glue to increase the speed and spin that can be produced. Most players still favour a less tacky topsheet, since it is less affected by the opponent's spin, while the speed glue increases the speed and spin produced by the sponge. This is supposed to give the player the best of both worlds, with more spin and speed of his own while being less affected by his opponent's spin. Some of the best Chinese players in recent years, are speed gluing their tacky rubbers with harder sponge to get a similar effect from their traditional type rubbers.
Thickness
The thickness of a topsheet can also vary between rubbers, although this is not important to most players buying normal rubbers made up of topsheet and sponge. It is important to those players who buy separate sponges and topsheets and then put them together, as they have to be careful that the total thickness of the combination is not more than 4mm, or the combination will be illegal according to the rules of competition.
Hardness
Again, the hardness of the topsheet can vary, with harder topsheets reducing the 'dwell time' and giving less spin than softer topsheets. Dr Neubauer actually produce an antispin topsheet that is completely stiff - very strange stuff to play against - like playing against wood!
Speed Glue
The subject of speed glue is worthy of an article of its own, but that is a topic for another time. Suffice to say that speed glue is used by advanced players to increase the spin and speed that they can produce. For shots involving spin, it will also increase control due to the increased spin.
Beginning players can and should avoid speed glue until their technique is solid - otherwise they run the risk of never developing their shots properly. Plus it's pretty darn expensive to glue up regularly due to cost of the speed glue and the reduced life span of your rubber, so unless you are a serious advanced player it's probably not worth the extra time and expense.
