In every training session, players use lots of balls. If they perform multi-ball training, then the number of balls used can exceed a hundred.
To supply this demand, factories produce millions of balls annually. The DHS brand alone produces 200 million balls annually.
One problem that ball manufacturers face is striking the balance between producing such a large number of balls while maintaining high-quality standards for each of them.
If I buy a DHS ball, play with it, and the quality is poor, I’m not going to care that the other 199,999,999 balls produced are of good quality.
Table tennis factories have to produce balls in the hundreds of millions while guaranteeing a satisfactory playing experience with each individual ball.
Table tennis players tend to be quite critical of the balls they use (sometimes using them as scapegoats when they aren’t playing well!), so companies must abide by strict production standards to make sure players don’t choose balls from other brands over theirs.
Companies have developed incredible production and testing methods to provide players with the quality they deserve. In this article, we will explain how the Double Happiness brand makes it happen.
We would like to thank DHS and the WTT channel for providing us with such insightful footage on the manufacturing process of the table tennis balls we all love.
Balls are crafted out of plastic sheets. The main material of the DHS plastic balls is cellulose acetate. D40+ balls are made from a different material, and many other manufacturers’ balls are made from ABS (Acrylonitrile Butadiene Styrene).
Before starting the production process, all the plastic sheets are weighed, measured, and checked for quality so that both halves of the balls are good enough quality.
Once the plastic sheets are selected, the production process begins by placing them on the assembly line.
Step 1: Shaping
The first step in the production of the balls is to shape the halves. The machines in the factory press against the plastic sheets and give them their circular shape.
While the machines are working, hot water is used so that the halves of the balls do not crack when under pressure.
Step 2: Edge trimming
The halves still have pronounced edges. In the next step, those edges are cut to ensure that the ball is even and that there are no negative effects on the bounce.
Step 3: Glueing
Operators place two halves on top of each other in the copper molds of the gluing machine, and the machine glues them together.
The solvent is applied evenly so the ball doesn’t peel off or break in half when playing.
At the end of this process, we have a complete ball. Balls are then distributed to another production process in which they are given their perfect circular shape.
In the DHS video, it is noted that this process is a trade secret.
Nittaku shared their video in which they show that the balls are chalked and then put into copper molds, where they’re subjected to very high temperatures. Presumably, this is how the balls get their perfect shape.
Step 4: Storing
After the balls are finished, they are stored in specialized sheds at a temperature between 45 and 50 degrees Celsius (approx. 117 degrees Fahrenheit) and a specific humidity.
This way, they acquire the right hardness and optimal playing characteristics.
Step 5: Quality control
The most important step in the whole process is quality control. It is thanks to quality control that we always receive round balls.
Although all the balls are built using the same method, the result is not always the same since the machines do not have absolute precision, the operators do not always put the sheets in the same way and the sheets themselves are not perfect.
Because of this, there are going to be some higher quality balls and others that aren’t up to par. In quality control, it is decided which balls are branded as training balls, which ones as 1-star, which ones as 2-star, which ones as 3-star, and others are discarded and recycled.
The first step in quality control is to pass the balls through the automated assembly line. There are automated machines that can estimate how good a ball may be.
This way, potential competition balls are decided, and these high-quality balls must be tested by hand.
To ensure the highest quality, DHS always checks competition balls multiple times. They use five manual steps to check the quality of the balls.
The first step of manual quality control is to check the surface of the table tennis ball. Operators hold the ball by the seam and inspect it under a lamp, discarding balls with an imperfect surface.
They must pay attention to the seam and the integrity of both halves. The video shows a ball that has an uneven seam. Hence, it gets sorted out.
The second step is to test the veer of the balls. In this process, balls are released onto a wooden table at a specific angle. If the ball veers more than 175mm, the ball is disqualified.
Step three is to test the hardness. A special device can measure the hardness of the balls in different spots.
The seam of the ball is placed parallel to the base of the machine and the hardness of both sides is tested. The balls are then recategorized by the difference in hardness.
This is why balls of different price categories feel different.
If you have ever played with training balls and 3-star balls, you will find that 3-star balls feel more solid. This is because they have superior hardness and quality. Higher quality balls are more stable and predictable.
The fourth step is to weigh the balls. Balls must weigh between 2.68 and 2.76 grams to pass.
According to point 2.3.2 of the ITTF handbook, the ball shall weigh 2.7 grams. For the balls to maintain the approval of the ITTF, the weight must fall within the tolerances indicated above.
The fifth and final step is to measure the roundness. For the balls to be approved, the deviation on the measuring machine must be between 2 and 2.4 millimeters.
The size of the ball must be between 40.0 and 40.4 millimeters.
Step 6: Logo Printing
In two steps, the DHS logo is applied to the table tennis balls. Red inscriptions (stars and seal of approval) are applied first, followed by the black text of the DHS brand.
Step 7: Packaging
Once the balls are ready, it’s time to ship them all over the world. The packing machine is automatic and it can pack up to 1,200 balls per minute. The whole production line can produce 600,000 balls per day.
After being packed, the operators put the boxes into larger cardboard containers and send them to the different official DHS distributors around the world to sell the balls to all table tennis players.
Frequently Asked Questions
What size is a table tennis ball?
The official table tennis ball is 40mm.
However, since 2014, plastic balls come with the inscription “40+”. Have you ever wondered what it means?
The reason for the 40+ inscription is that previously 40mm celluloid balls could fall between 39.6 and 40.4mm in diameter.
Since the production of table tennis balls is on a very large scale, manufacturers wanted to get as close to the lower limit as possible to save costs, and thus most celluloid balls were closer to 39.6mm than to 40mm.
When the ITTF introduced the plastic balls, they asked the manufacturers to make the balls 40 millimeters or larger, that is why the plastic balls are said to be bigger, hence the inscription 40+. The smallest approved plastic ball is 40mm in diameter. It can be a bit bigger, but not smaller.
What are table tennis balls made of?
Table tennis balls were made of celluloid until 2014 when they were replaced by plastic balls.
This change was because celluloid was an obsolete material, the only purpose of the material was to produce table tennis balls.
In all other areas, celluloid had been replaced by other more environmentally friendly materials, since celluloid is highly flammable and quite toxic.
Current balls are mostly made of ABS (Acrylonitrile butadiene styrene).
What is the difference between 1-star and 3-star ping pong balls?
What is the difference between plastic and celluloid table tennis balls?
The difference between the plastic ball and the celluloid ball is that the plastic ball is harder.
Due to this, the spin in the sport was drastically reduced, and so the techniques and tactics of the players changed.
With the celluloid ball, the game was slower and more spin-dependent. The predominant style with the plastic ball is the offensive style close to the table with quick counters on both sides.
Defenders, mid-range players, and spinners were the ones that suffered the most from the ball change, while short-range attackers who use speed over spin, such as Tomokazu Harimoto, benefited greatly.
Alvaro’s been playing Table Tennis since he was 15 and is now ranked within the top 100 in his native Argentina. He loves to compete in provincial tournaments and is always looking for ways to improve. Alvaro made his favourite memories with a racket in hand, and he joined the RacketInsight team to share his passion with other players!