Ping pong ball

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3-star balls 40+ made of plastic, diameter 40 mm - with current ITTF approval
3-star balls 40 made of celluloid, diameter 40 mm - no longer internationally approved

The table tennis ball is used in table tennis . The properties of the balls are prescribed for official competitions: As of 2018, the ball will only be made of plastic . Since December 31, 2017, the production of table tennis balls made of celluloid has been discontinued worldwide because celluloid is considered highly inflammable and therefore no longer transportable. It is hollow, evenly round, should have a diameter of 40 mm and should weigh 2.7 g. If it is dropped from a height of 30.5 cm onto a standardized steel block, it must jump off 24 to 26 cm.

Prescribed properties

Section 3 of the “Table Tennis Rules” manual deals with the table tennis ball. The following provisions are taken from this (as of April 2019):

  1. The ball is spherical and has a diameter of 40mm.
  2. The ball weighs 2.7g.
  3. The ball is made of plastic. It's matte and either white or orange.

Quality standards

Standard color white
Standard color orange
Table tennis ball, cut open - inside view of the seam
TT training ball for spin detection

High demands are made on the material and processing of a ball. A hard hit "smash ball" can reach speeds of up to 170 km / h. The ball only touches the club for about 1/1000 of a second and is deformed by up to 25 percent.

If the topspin is hit optimally, the ball spins about 150 times per second or 9,000 times per minute.

Table tennis balls are therefore offered in different quality levels depending on the requirements in training or competition performance. The highest quality level is marked as a selected "3-star ball", the lowest (less than 3 stars) are sold as training balls. The labeling is not reliable, however, as manufacturers sometimes label their balls with three or more stars without meeting the quality requirements for a table tennis ball suitable for competition. The classification as a 3-star ball only results from a complex selection (for weight, hardness and rounding) after production.

Table tennis balls can be seen as a kind of consumable item because they break regularly (depending on the quality and style of play). In most cases, the balls will tear at the seam. Experienced players usually recognize this immediately by the sound or jumping behavior.

Because at the high flight and rotation speeds even minimal deviations of the ball have a significant impact on the flight path and the jump off the table, 3-star balls are mandatory for competitions.

Training balls can differ significantly; The highest quality are those balls that have been sorted out from the production of the competition balls because of deviations in mass, hardness or roundness. There are also balls made of inferior celluloid that have already been produced as training balls. Table tennis balls with an outwardly curved seam are largely no longer available today.

The classifications "1-star-ball" and "2-star-ball" that used to be found have largely disappeared from the manufacturers' offer due to a lack of demand. These balls are now usually sold as training balls.

Quality inspection

The Süddeutsche Kunststoff-Zentrum (SKZ) in Würzburg has been testing since the beginning of the 2000s on behalf of the International Table Tennis Association ( ITTF ) whether a table tennis ball meets the properties required by the ITTF. There are around 70 product lines. Each of these series is checked every two years. For this purpose, 24 balls are randomly purchased. The color value of the balls is determined with a spectrophotometer , then they are weighed. An inclined plane is used to measure whether the balls are rolling straight ahead. Since the halves are joined together by means of a weld, there may occasionally be deviations. The jump height is measured with the help of a digital camera. Then it is tested whether the balls are evenly round. A ball is rotated in a measuring device and the diameter is measured 200 times in the various planes. Finally, a pressure is generated with weights, whereby a ball may deform between 0.71 and 0.84 millimeters under a load of 5 kg.

Manufacturing

For the production of a table tennis ball you needed celluloid plates from which small, round disks are cut out or punched out. Heated to around 100 ° C and pressed into a hollow shape using a deep-drawing process , the disks are transformed into hemispheres with a rim. The edges of the hemispheres are cut and glued together with acetone . This raw shape of the ball is now trimmed again at the glue seam and then inflated to the final size by heating in a spherical shape. The balls are then given their final weight and shape in a rotating drum with the help of pumice powder.

After production, the balls go through a selection process that automatically checks them for weight, hardness and roundness. The balls must be stored until they are used to allow solvent residues to evaporate. This often takes place during the several weeks of transport by ship from Asia, where the balls are manufactured today, to their place of use.

In the 1980s, an attempt to make the balls from a different plastic failed. The table tennis balls sold under the name of the table tennis legend Victor Barna are characterized by an extremely long durability, the plastic used for production was almost indestructible under playing conditions. However, after a short playing time the surface became so smooth that the "top spin" or "undercut" techniques were no longer an option. This problem could not be solved and the novel plastic ball disappeared from the market.

Since around 2010 it has been possible to produce balls of the same quality from plastic (e.g. ABS ), which then gradually replaced the celluloid ball.

Colours

Table tennis balls are available in different colors, including white, orange and yellow (since 1970) and with colorful prints. However, only matt white and matt orange balls are permitted for the competition. Yellow balls were banned in 1997 at the Biannual General Meeting (BMG) . Contrary to popular belief, it is not necessary to play with white balls on green tables or with orange balls on blue tables. Rather, any of the color combinations are permitted. For training purposes there are also two- or three-colored balls such as red-white or red-white-blue, so that the rotation can be better recognized.

The development of colored (yellow or orange) balls is based on the studies carried out at the end of the 1960s and beginning of the 1970s at the TU Braunschweig by the lecturer and then federal instructor of the DTTB, certified sports teacher Martin Sklorz, which showed that yellow balls can be seen better by the player than white balls. The first tests in competition took place in May 1970 at the German Junior Cup in Ettlingen. The first colored balls were manufactured and sold by the Hanno company. It took almost two decades for this innovation to catch on in competition operations.

history

The English engineer James Gibb brought the celluloid table tennis ball, which was in use until 2018, from a trip to America in 1890/91. Before that, rubber balls or carved cork about five cm in diameter had been used to play. The celluloid balls were soon made by machine. In 1902 Essex, England produced around 2 million balls a week.

Around 1969 one experimented with yellow balls for the first time, whereby initially the jumping behavior of the ball deteriorated due to the addition of the yellow dye used at the time - the balls became softer. These problems were later resolved by using other dyes.

In 1990 it was estimated that more than 10 million balls were used in Germany every year.

At the 2000 World Cup , the ITTF Congress decided to increase the diameter of the ball from 38 to 40 millimeters. The next World Cup was the first to use the big ball. The changed trajectory required a great deal of adjustment from the players. The defenders in particular had problems. At this World Cup, many defenders were eliminated early, and none of the women made it to the last sixteen.

Before 2000, smaller balls were used. The diameter was 38 mm (tolerance 38.2 mm to 37.8 mm), the weight was specified as 2.5 grams (tolerance 2.40 to 2.53 g). A competition ball would have to bounce up 9 to 10 inches if it fell onto a steel block from a height of 12 inches. The flight speed should be reduced by enlarging the ball to 40 mm. It was hoped that this would result in longer and more attractive rallies as well as better visibility of the ball for spectators on site and during television broadcasts. However, these properties were not achieved because table tennis bats have also been further developed in the meantime . Faster clubs and rubbers that are easier to bounce meant that the ball speed remained the same despite the larger ball.

The plastic ball

Table tennis plastic ball 40+
+ Sign after the number 40 means: plastic ball

In June 2011, the German Table Tennis Federation DTTB and the World Association ITTF announced that a new ball would be introduced after the 2012 Olympic Games . The aim was to switch from celluloid to plastic balls; The reason given was that it would be difficult to produce balls from celluloid in the future, as their production would be banned in some countries. In addition, the balls are classified as dangerous goods due to their high flammability. At the same time, officials were told that there would be only minor differences to the old ball, as the size and weight would be retained. Top Chinese players also found this out after tests with the new ball. However, the tolerance dimensions have been changed to 40.0–40.6 mm (previously 39.5–40.5 mm), so that the balls are larger than celluloid balls, as the companies often used the lower end of tolerance for their production.

As early as 1970 the Dunlop company developed a plastic ball, but it did not catch on. On September 15, 2005, the German chemist Thomas Wollheim and In Sook Yoo, as inventors, applied for a patent for a celluloid-free table tennis ball with In Sook Yoo International Project Management as the applicant. Since the patent law situation seemed unclear to the manufacturing companies, they hesitated to manufacture plastic balls. They also criticized possible economic ties on the part of Joachim Kuhn, husband of In Sook Yoo. From 2000 to 2013, Kuhn was named in the ITTF Technical Leaflet T3 (definition of the criteria for ball admission) as the ITTF Material Committee member responsible for ball tests. He resigned from the Materials Committee in 2013.

New plastic balls were approved for the first time in early 2014. The much-criticized Palio ball was not among them (see list of permitted balls). Since July 2014, only the new plastic ball has been used internationally. The DTTB recommended doing the same in the leagues it administers. At tournaments organized by the ITTF, the plastic ball has been mandatory since July 2014. Otherwise the celluloid ball is still permitted. The French table tennis federation FFTT decided not to introduce the plastic ball in its national leagues. From the 2016/17 season, the DTTB will make the use of the plastic ball mandatory in the national leagues. For all lower classes, including amateur classes, the plastic ball is mandatory from the 2019/20 season in Germany.

At the beginning of 2017, the table tennis company DHS (Double Happiness) presented a new generation of plastic balls. These balls not only have a greatly improved durability, but can also be offered more cheaply compared to the previous plastic balls. However, the new plastic balls take on even less rotation, which increases the differences in playing characteristics between the celluloid ball and the plastic ball.

At the beginning of 2020, top players were still criticizing the different playing properties of plastic balls from different manufacturers. This often has a disadvantageous effect, especially in top-class sport.

various

  • The table tennis ball as a collector's item is a rather unusual hobby in general, but one that appears now and then among table tennis players. Dieter Lippelt from Niedermark showed 5,800 different balls in Düsseldorf in 1998.
  • Stanislaw Schmidt is the first table tennis ball collector who exhibits his collection online and thus gives a comprehensive overview of the variety of table tennis balls.
  • The drawing machines of the German Lotto (6 out of 49) are equipped with 49 lacquered table tennis balls.
  • In 1999, Japanese and British scientists simulated the behavior of avalanches for study purposes by rolling 32,000 table tennis balls down a ski jump. In 2004 the experiment was repeated with 550,000 balls.
  • At outside temperatures of 34 degrees Celsius, 500,000 table tennis balls in a metal container exploded in Hong Kong.
  • In the Jugend forscht competition , Felix Kahlhöfer (Düsseldorf) examined chaotic effects with the help of a table tennis ball by attaching a glass plate to a loudspeaker and making the ball bounce with different sounds.
  • Celluloid table tennis balls are considered dangerous goods and may not be sent in small packages or parcels by DHL . Celluloid consists u. a. made of cellulose nitrate , which is also known as gun cotton and is subject to the German Explosives Act.
  • Almost 90% of all table tennis balls produced worldwide are supposedly used for salvaging shipwrecks. However, this is only a myth inspired by a Donald Duck story, which was only successfully recreated once for an episode of the television series MythBusters - The Knowledge Hunters . The cost of around 100 million table tennis balls that would be needed to lift a medium-sized freighter is about the same as buying a new ship.
  • In the 2013/14 season, the playoff games of the Chinese Super League were played with a two-tone plastic ball on a trial basis. Half of the ball is white, the other half is orange. This should make the ball rotation easier to see for the spectator.

See also

literature

  • Martin Sklorz: Again: Yellow table tennis balls , presentation of the advantages and disadvantages, In: DTS . 11, 1970, edition Süd-West, p. 15.
  • Jörg Petrasch, Konrad Tiefenbacher: Physics in the interaction of racket / ball / table. In: table tennis . 1, 2010, p. 51; 2, 2010, p. 50; 3, 2010, p. 50.
  • Jörg Petrasch, Konrad Tiefenbacher: Physics - All kinds of resistance. In: table tennis. 5, 2010, p. 50.
  • Susanne Heuing: Whirling around the new ball. In: table tennis. 7, 2013, pp. 12-13.
  • Horst Biese: 100 year old object of desire. In: DTS . 1, 1991, p. 22.
  • Rahul Nelson: Bigger Ball - The Power of Millimeters. In: DTS. 1, 1999, pp. 30-31.
  • Rahul Nelson and others: Series of articles about the table tennis ball, In: table tennis . 6, 2004, pp. 18-23.
  • Susanne Heuing: Plastic Ball - The fronts are hardened. In: table tennis. 8, 2013, p. 34.
  • Susanne Heuing: The plastic ball is coming - for everyone. Questions and answers on the subject of plastic balls:… In: table tennis. 1, 2014, p. 39.
  • Susanne Heuing: Experience with the plastic ball. In: table tennis. 11, 2015, pp. 10-13.

Web links

Commons : Table tennis balls  - Collection of pictures, videos and audio files
Wiktionary: table tennis ball  - explanations of meanings, word origins, synonyms, translations

Individual evidence

  1. ↑ Table tennis rules A. (PDF) Retrieved on April 17, 2020 .
  2. ↑ Values ​​measured in 1970/71 at the TU Braunschweig by Martin Sklorz, federal instructor of the DTTB.
  3. ↑ Focus Online Interview with Timo Boll .
  4. ↑ Helmuth Ziegler: Ball test - ballisticians make the acid test. Tischtennis magazine , 2006/3, pp. 46–47.
  5. ↑ DTS magazine , 1997/6, p. 15.
  6. ↑ Journal DTS , 2001/6, pp. 12-13.
  7. ↑ DTS magazine , 2010/5, p. 53.
  8. ↑ a b It's not ticking properly! FAZ Technik & Motor, June 4, 2014, accessed December 20, 2014.
  9. ↑ DTS magazine , 1970/9, p. 10.
  10. ↑ Patent EP1924331 B1 (accessed on July 6, 2013)
  11. ↑ The battle for round plastic Süddeutsche.de, July 16, 2014, accessed on December 20, 2014.
  12. ↑ ITTF Technical Leaflet T3 (June 2003 version) (PDF; 127 kB).
  13. ↑ The End of the Ping-Pong-Ball Zeit online, September 24, 2014, accessed on December 20, 2014.
  14. ↑ Notice from the DTTB on the new plastic ball ( memento of the original from December 20, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Tischtennis.de, accessed on December 20, 2014. @1@ 2Template: Webachiv / IABot / www.tischtennis.de
  15. ↑ DTS magazine , 2014/5, p. 4.
  16. ↑ DTS magazine , 2019/9, p. 7.
  17. ↑ table tennis balls . Retrieved September 3, 2017 .
  18. ↑ Ricardo Walther: Plastic is not just plastic in: DTS magazine , 2020/3, p. 11.
  19. ↑ DTS magazine , 1998/6, p. 20.
  20. ↑ www.tischtennisbaelle.org - The first table tennis ball collection on the web. Retrieved April 1, 2014 .
  21. ↑ Table tennis balls and a fairy decide who wins the lottery. Retrieved April 1, 2014 .
  22. ↑ Journal DTS , 1999/11, p. 6; 2004/3, p. 5; What table tennis balls have to do with powder snow avalanches
  23. ↑ DTS magazine , 2001/9, p. 6.
  24. ↑ DTS magazine , 2004/6, p. 7.
  25. ↑ Permitted content (valuables and dangerous goods). Retrieved April 1, 2014 .
  26. ^ Records and other curiosities Austrian Table Tennis Association . The EM starts on Friday in Schwechat. The guide to a fascinating sport. kurier.at, October 3, 2013.
  27. ↑ Ping pong balls and balloons .
  28. ↑ Series of publications by the Badische Anilin- & Soda-Fabrik, issue 16, p. 53.
  29. ↑ DTS magazine , 2014/8, p. 43.