Tennis Balls

Before I started stringing rackets, I never paid much attention to tennis balls. Yes, there are certain brands I prefer, like Slazengers, but that's about it. I don't know the mass of the ball, nor its diameter, or how long I've used it.

According to the International Tennis Federation (ITF), tennis balls dropped onto concrete from a height of 254 cm (100 inches) must rebound  between 135-147 cm (53-58 inches). (link)

I gathered all my used tennis balls and started measuring their bounce from a drop of 254 cm. It's amazing how varied the bounce height of those balls were.

I sorted them into 4 groups. The "baldy" on the left bounced way above 147cm. The second group is within regulation. The third failed just marginally. And the last group could not even make it to 120cm!

From this simple experiment, I got a confirmation that my "feel" is very much intact. Just from playing, I've actually segregated those balls I liked from those I didn't. And everyone of those I liked were within regulation :)

If you have time, I think you should test your tennis balls too. It makes a GREAT difference on how your strings would feel. Try playing with a few in-regulation balls for a few minutes, then swap to those balls that just failed marginally. You will notice your racket stringbed would feel muted immediately with the flat balls!

So it makes sense to open a can of new balls whenever new strings are installed.