Theory of Spin

Rowden Fullen(2000)

  • In 1960 Jacobson brought the loop back after training in Japan and became a sensation in England beating all comers.
  • The initial loop technique was with a ‘fine’ touch and slow, with a high arc. This type of loop had an unpredictable bounce due to the ‘Magnus’ effect. Often the ball dropped low very quickly causing problems for defensive players.
  • There was a big difference between the hard rackets of the ‘50’s and the modern sandwich rackets. The new surface was much softer and more ‘tacky’ allowing the ball to sink in and be gripped. As a result the contact angle used to strike the ball changed dramatically. Players were able to strike the ball with a much more closed racket angle, which resulted in very much increased topspin.
  • Using a more closed racket angle not only could players achieve much more spin, but also they had the capability of hitting the ball much harder and still getting it on the table!
  • Striking the ball with a closed racket angle with power means SPIN. The harder the player can hit the ball the more SPIN is generated. Women have a lesser capability than men do to hit the ball really hard.
  • We are aware that it is necessary to have a ‘thin’ contact in order to achieve good spin. However if the contact is too fine, we will not produce strong spin, however much force we apply. This is of course because the ball is not given enough friction and it will just slide off the bat surface without being held long enough to obtain the required effect.
  • Spin affects the ball in flight and after bouncing. This is known as the ‘MAGNUS’ effect and is to do with the high-pressure part of a spinning object impacting against the air pressure. Generally with topspin there is a smaller angle after the bounce and with backspin a larger one.
  • Sometimes with the slower loop, high with spin and no speed, we encounter unusual bounces. This is to do with the angle of contact with the table. Because the prime speed is downwards, the ball ‘kicks’ up first, then ‘drops’ low very quickly. The same happens with the fast chop especially if this is taken early against a rising ball. The return ‘comes through’ fast and instead of ‘kicking’ up skids through very low.