How to Make a Tennis Ball

My engineer brain is fascinated with how things are made. The process for manufacturing tennis balls is complex to the point that I was astonished this morning to find someone selling custom hand made tennis balls on Etsy.

While these balls most certainly do not appear on the ITF approved ball list, the description of how they are made seems to be legitimately in alignment with how the sanctioned balls are made. Unfortunately $26 for a sleeve of three pretty much precludes further evaluation on my part. I mean, that’s about the same price as a good pair of singles sticks.

The ITF provides a description of the manufacturing process for balls from the approved ball page. An example formulation for the core of the ball is provided, which is about 50% rubber. The core also contains many other substances including Clay, Zinc Oxide, and Sulfur. I am wondering which of these produces the characteristic tennis pro shop aroma. My money is on the sulfur.

There are a couple of great videos available on the ball manufacturing process. Tennis players who are loyal to Wilson balls will enjoy this video, while Penn aficionados will like this one.

While the ITF indicates that there are two types of fabric used to cover tennis balls, this information might be dated. The ITF indicates that either Melton cloth which has a high wool content or Needle cloth are used. The Needle cloth has more synthetic fibers and is cheaper to produce.

According to a web page published by Penn Europe, their balls use a combination of New Zealand wool and synthetic fibers. I was looking for similar ball composition information for Wilson balls, but instead stumbled across the following astonishing assertion.

“The United States Open and other American hardcourt tournaments use regular felt balls instead of extra duty for women’s matches because they produce a faster style of play.”
“Which Tennis Ball is in Use? It Makes a Difference,” New York Times

I am astonished to learn that different balls are used for the dudes than what are used for the ladies matches. My engineer brain also sprints to the edge case, wondering which ball is used for mixed doubles. I am sure that I will be writing about this more in the future.

I have high brand loyalty to a particular brand and model of ball that I recently was thrilled to learn contains New Zealand wool in the felt. It is also an extra duty ball, which should result on a slower style of play. Anyone who has ever watched me play will attest that slow is a pretty good summary of my game.

Before writing this essay, I would have said that my ball preference is based on how well the ball holds up over an extended match or training session and how consistent the fuzz stays across play. Now I am wondering if my affection for a certain ball is also rooted in it being a good match for my personal style of play.

The more I learn on this topic, the more I wonder whether I should be rotating different balls in my practice sessions just for the variation.

True confession time, there is one brand of ball that I loathe to the point that I once intentionally dispatched one of the balls over the fence and then magnanimously opened a new can of the ball that I prefer for the remainder of the match.