The pressure of a tennis ball is one of the most important factors that will affect the whole game. And one of the problems that many tennis players face on a daily basis is that tennis balls simply lose their pressure with time. This forces players to go through hundreds, even thousands of balls simply because they lose their pressure.
How to keep tennis balls pressurized? Keeping the tennis balls unopened is the best way to keep them pressurized. Once opened, tennis balls will start to lose their pressure. To keep used tennis balls pressurized, make sure to keep them in a pressurized storage container at room temperatures.
To learn more about everything you need to know about how to keep modern tennis balls pressurized continue reading below.
Why Do Tennis Balls Lose Pressure?
Tennis balls are built in a special way. They have internal pressure, which is higher than the atmospheric pressure outside. In other words, the internal pressure creates a force that pushes from the inside out. This affects the bounciness of the ball.
The surface of the ball is composed of a rubber-like material that is covered with felt. This material, however, is not completely inert or non-porous. And what this means is that the air inside the balls will slowly seep through it and leak out.
With time tennis balls will start losing their felt, including the plasticity and structure of the rubber material. The more the ball is used, and the harder the hits are, the faster the ball will wear out, ultimately speeding up the loss of pressure.
This is a completely natural process. For the most part, once a tennis ball is taken out of its can, the loss of pressure cannot be avoided. However, certain things may help us improve the longevity of a tennis ball.
What Is the Best Way to Keep Tennis Balls Pressurized?
Unopened Tennis Balls
The best way to keep tennis balls pressurized is by leaving them in the can unopened. However, unopened tennis balls will not last indefinitely. There is always the possibility of micro leaks and overall material degradation with time. Unopened tennis balls may be able to stay good between 2 to 4 years.
Keep the balls in climate-controlled places. Usually, it is best to keep your tennis balls inside your home—the closet or the laundry room are also acceptable locations. You can also keep tennis balls in your basement where the temperatures will remain relatively stable throughout the whole year.
Some players may keep tennis balls in the trunk of their car, but this is not a good place, so avoid it as much as possible.
So unless you will be using the balls, don’t open the can and keep it at room temperatures.
Opened Fresh Tennis Balls
Unfortunately, once the can has been opened, the balls will start losing their pressure no matter what you do.
Fortunately, there are some methods that we can use to extend the life of a tennis ball.
Using a pressurized storage container like the Gexco Tennis Ball Saver on Amazon is a great way to maintain the pressure of your tennis balls.
This tennis ball storage container is going to keep the tennis balls under equal internal and external pressure, which is about 14 psi. That way, the tennis balls will retain their pressure for much longer.
You can keep your tennis balls in the container, and when you need them, all you have to do is take them out and voila you have a few fresh tennis balls to play with.
Opened Old Tennis Balls
The more you play, the faster the tennis ball will wear off. It will start losing its fuzz, and the rubber may get harder with time due to use and heat exposure. All that will affect the structure of the ball and its ability to maintain its pressure.
This is why older tennis balls should ideally be kept in a pressurized storage container; however, they will lose their pressure a lot quicker compared to new and fresh tennis balls.
Older tennis balls are best used for a tennis machine or a wall practice.
Can You Re-Pressurize Tennis Balls?
Older tennis balls that have lost their bounce can be re-pressurized. It is a fairly slow process, but it does work.
To successfully re-pressurize dead tennis balls, you need to place them in a re-pressurizing container that can create a higher pressure than the one inside the ball.
The ideal pressure range is between 30 to 32 psi. Applying to much pressure, however, about 35 psi or so, will crush the balls. Conversely, very old and worn-out tennis balls may even crush at 30 psi.
Tennis balls have to be stored for about two weeks at appropriate pressure levels to be successfully re-pressurized.
With that being said, re-pressurizing a tennis ball will not always bring back its old glory days, so to speak, as it will not have the same bounce.
The pressure inside new tennis balls out of the can is usually very consistent. There is very low variance, while re-pressurizing old tennis balls can give you mixed results.
The problem comes from various factors like:
- The accuracy of the pressure gauge; and
- The overall condition and age of the tennis ball;
Because of these variables, there will be some trial and error involved in the process. You will have to test each one of the balls as some may be bouncing more while others significantly less.
For a really cool DIY tennis ball re-pressurizer, check out the video below.
What Is a Good Tennis Ball Pressure?
The simplest way to find out if a tennis ball has proper levels of pressure is to give it a gentle squeeze. The ball should feel firm but give ever so slightly.
Usually, this is done by measuring the bounce of the ball. According to the rules, a tennis ball dropped from 100 inches on a concrete floor should bounce up to between 53 to 57 inches.
The pressure of tennis balls will vary from manufacturer to manufacturer. So the numbers do vary within certain ranges.
Usually, the pressure of tennis balls is between 1.2 and 2 atm (or 14.7 to 29.4 gauge pressure).
How Long Will a Tennis Ball Stay Pressurized?
If you have been playing tennis for a while, you already know that tennis players can go through a lot of tennis balls—especially the pros which will be using new tennis balls every 30 to 60 minutes.
Tennis balls maintain their pressure at optimal levels for the first one to three hours of play. The more you play and the harder you hit, the faster they will lose their pressure.
If you leave tennis balls out in the open, they will continue losing their pressure at very slow rates even if they are not used. After a couple of weeks, about one to two, the difference in pressure can become very noticeable.
What Happens If a Tennis Ball Is Not Pressurized?
The pressure of the tennis ball affects its behavior on the court—its bounciness, trajectory, spin, and movement.
Old tennis balls that have lost much of their pressure are often called dead tennis balls.
Dead tennis balls, generally speaking, are not harder to control, but they do not bounce much.
Another problem that tennis players face is that the different tennis balls will depressurize at different levels.
Some dart players may even outright refuse to play with tennis balls that do not have proper pressure as these balls will affect the pace of the game, which can be very frustrating.
And if that is not enough, older tennis balls that do not have adequate levels of pressure are also associated with injuries. Some players report that hitting dead tennis balls hurts their arm, wrists, and shoulder more compared to hitting new fresh balls.
Are There Pressureless Tennis Balls?
Even though you will not have to worry about the balls losing pressure anymore, pressureless balls are not very popular. The main problem with pressureless tennis balls is that they are heavier, do not bounce well, and there may be a higher incidence of injuries associated with them.
This is why they are used for practicing serves or use with a tennis ball machine and not much else.
There are also the ROG (red, orange, and green) tennis balls that have lower pressure than the standard tennis balls. These are also known as low-compression tennis balls and are usually used as introductory tennis balls for new players and especially for kids.