Q1: What is the most common material for racquet string?
A1: Right now Nylon (polyamide) is the most common material. Many different combinations of nylon produce many different string characteristics.
Q2: What is “synthetic gut”?
A2: The term “synthetic gut” has very little meaning in terms of string quality. Typically “synthetic gut” is the term applied to any string that has more than one filament.
Q3: What is the most popular string gauge, or diameter?
A3: For the moment 16 gauge, (1.30mm-1.32mm), .050, diameter is the most common gauge.
Q4: What is a “hybrid”?
A4: A hybrid is a combination of two (2) different strings in a single racquet. The differences can be as slight as color differences or gauge, or as significant as two (2) different string materials. The most common, right now, combination is nylon and polyester.
Q5: How long will string last in a sealed package?
A5: A lot depends on how the package is stored. If it is subjected to extreme temperature variations I would toss it after one (1) year.
Q6: How long will string last in a racquet?
A6: If a string is properly installed in a racquet and never hit with it you can expect it to last for many years! This is why we need to determine how many hours your customer uses the racquet per week, or month.
Q7: When should I re-string my racquet?
A7: In reality most racquet strings lose enough tension in 20 to 25 hours that you should consider stringing if you want the best possible performance. Of course many players can, and will, play with string for months without, in their opinion, a downgrade in the performance.
Q8: How do I know what the tension in my string is?
A8: There are a few devices that can give you this information. However, the information you will get is the “string bed stiffness” not the tension on each individual string.
Q9: Should I pre-stretch string?
A9: Pre-stretching string can do no harm if the elastic limit of the string is not exceeded. It would be nearly impossible for a person to pull the string hard enough to damage it. I prefer pre-stretching in a single long piece and not, necessarily, on the stringing machine. Pre-stretching can stabilize the string as well as make it a little easier to handle.

The String Breakers Dilema

What’s the perfect solution for the string breaker? The truth is, there isn’t one, unless you’re the type of player who could care less about the “feel” of the racquet and stiff strings have no physical effect on you. To understand this issue a little better, let’s look at some different types of string breakers.

1. AVERAGE string breakers are those that may break strings once in a great while. In fact, they might even feel proud of themselves that they actually broke a string for a change. WOW—am I hitting the ball that hard?

2. FREQUENT string breakers will break strings every 3-4 weeks. This is the category that’s the most difficult for the stringer to address. These players are usually playing at the 4.5 NTRP level or higher, and serving withgood pace and hitting the ball with heavy slice or topspin off the ground. Because of their level of play, they’re usually more sensitive to the “feel” of the racquet, preferring a lighter gauge (thinner) string or maybe even natural gut to enhance the control and touch they seek from the racquet.

3. CHRONIC string breakers can and often do break strings every time they walk onto the court. A set of string might last them one set of tennis and they know that if they get 2-3 hours of play from a string job they’re doing good. Keep in mind that there are a multitude of strings on the market and many are targeted at string breakers. However, remember that as with any product, there’s a certain level of marketing jargon that accompanies any product and strings are no exception.


AVERAGE string breakers need not worry. You’re not breaking strings often enough that it becomes an issue. Remember to string on a regular basis and you should be ok. A general rule of thumb is to restring as many times a year as you play each week and you should be fine.

FREQUENT string breakers have to be more involved with their stringer. There are strings that can solve your problems of premature breaking, but they’re much stiffer than a typical synthetic. These usually include Kevlar and polyester hybrids, which consist of different main and cross strings. The mains (vertical) strings are where the Kevlar or polyester is used, and the crosses (horizontal) strings will be a typical synthetic gut or natural gut if you choose to use the very best. Another option is to switch to a thicker gauge version of the current string you’re using if it’s available. Either way, you’re going to give up a lot of “feel” in your racquet and most of the time players at higher levels aren’t willing to make that sacrifice. In that case, make sure you’re using a racquet with a tighter (more dense) string pattern and try string savers. These little devices can enhance the overall life of the string, sometimes doubling it. There is some debate about whether string savers affect play or tension but it’s been the authors experience that string savers have such little affect on either that it becomes a mute point. If you question the viability of these little devices you needn’t look any further than Pete Sampras for their justification. Pete’s been using the Babolat Elastocross for quite some time now and it didn’t seem to keep him from winning a few Wimbledon & U.S. Open titles. Their basic function is to minimize the notching that takes places when the main and cross strings rub against each other during play.

CHRONIC string breakers are rarely found at the recreational level so many stringers don’t need to worry about this too much. However, if you’re working with satellite or professional level players it’s a different ballgame. Even then, it’s somewhat of a non-issue because these players will string after each match, whether or not the racquet was even used. The name of the game for these players is maximum control, not durability, and most of these players are on some sort of program with their string supplier anyway, so cost is not a factor.

Keep in mind that there are a lot of reasons that make strings break or lose their tension much too quickly. A few of these are:

  1. Construction or physical make-up of string used
  2.  Gauge of string used
  3. Frequency of play
  4. How much time you play – most synthetic strings are good for an average of 20-30 hrs of play before they start losing their zip & feel
  5. Style of play—meaning excessive topspin or slice as opposed to hitting flat (no spin)
  6. String pattern density of the racquet
  7. How hard you’re hitting the ball
  8. Framing a ball—hitting the ball off of the side of the frame, which results in tremendous stress on the string where it enters the grommet, usually snapping the string at impact. There’s nothing your stringer can do to correct this problem. This is player induced
  9. Subjecting a racquet to extreme temperature changes—leaving it in the car in the heat of the day even for a short time can cause the strings to lose tension. Checking your racquets at the airport is another no-no. From ground zero to 30,000 feet the temperature can go from 80 degrees to well below zero in less than 10 minutes and your racquet strings will pay the price. Many airlines now have temperature controlled storage spaces but we could not verify if all do. In short, it’s best to carry on your racquets if possible
  10. Stringers error—I’ve seen some pretty terrible string jobs and many mass retailers use inexperienced employees to do their stringing. This inexperience can result in sloppy, loose string jobs, miss-weaves, notching of the string during installation, and damaging the string by trying to force an awl through a shared hole for the tie-off. Racquets can pay the price too due to incorrect mounting prior to string installation. Ask questions before you turn your racquet over for service. Find out who does the stringing, are they certified, a member of any organization that offers training & testing to sharpen their skills, or simply the kid that was pulled out of the scuba diving section because someone needed a string job!

Racquet stringing is certainly not rocket science, but there are a lot of factors involved in determining the right string for each individual player. The best thing you can do is find someone you’re comfortable working with and stick with them for as long as you can. Consistency is a major factor and this comes from trust in the beginning and forming a good working relationship with your stringer. A good stringer will welcome the challenge of working with a string breaker and be happy to offer suggestions to solve any problem a player might encounter.

Top Ten Reasons for Premature String Breaks

There are so many reasons why strings break prematurely and as the racquet technician, you always have to be on your toes so you can avoid potential problems. Let’s take a look at some of the more common reasons for premature string breaks.

  1. Is the player using the right racquet for their style and level of play? An NTRP 4.5 player using a super oversize lightweight racquet should set off alarms for you right away. The players power level is too high and the pattern density on the racquet is too open for strings to last much more than a few hours of play. The racquet a player uses makes a significant difference as to how long the strings will last.
  2. Is  the player using the right string for their playing style, level of play, and most importantly, the racquet they’re using? (see #1) String selection is always a consideration and should match the player’s ability level and style of play. Likewise, if the string is mismatched to the racquet this can create problems as well. This is an area that will often separate a knowledgeable stringer from a novice so know your products and take the time to educate yourself on the differences in string.
  3. Players hitting with a lot of topspin or excessive slice should be cautious about using a thinner gauge string unless they’ve recently won the lottery and can afford to re-string every 6-10 games. Using a thinner gauge string for a player with this style is a complete mismatch. Spin can cause strings to move a lot, especially if the pattern is more open than closed. The strings will begin to notch at the junction where the crosses and the main strings meet and before you know it, the notch has worn too thin and the string breaks.
  4. Framing a ball is one of the most frequent reason for premature string breakage. This happens when the player doesn’t strike the ball in the center of the racquet and instead, hits the ball off the side of the frame. Half of the ball is on the frame and half of it is putting tremendous downward pressure on the grommet where the string enters the frame. As the stringer there’s NOTHING—repeat—NOTHING you can do that will prevent the strings from breaking if this happens.
  5. Cheap string is another culprit. Players think they’re saving money by trying to buy their own string but there’s no way to verify how well the string was stored or how old it is. As the stringer you can choose to educate your players to rely not only on your expertise but also on products you choose to stock and the reliability of the manufacturers you choose to deal with. Players who think they’re saving money by buying their own string and paying someone less money to install it actually end up spending far more money than they ever would have if they had relied on your experience as a stringer in the first place.
  6. We often see players who constantly drag the side of their racquet on the court when going for a low ball instead of bending at the knees to make the shot. This will eventually wear the bumper guard down to a point where protective channel in the bumper guard no longer protects the string. This leaves the string exposed (raised) to a level where dragging the racquet on the court will result in scrapping the string, eventuallyu causes it to break prematurely. Again, there’s nothing the stringer can do to prevent this. It’s purely due to the player’s technique.
  7. Old and brittle strings can be a problem as well. Strings becomes brittle due to improper storage or too little humidity in the air and become a prime candidate to break too early. As a professional stringer you have a responsibility to maintain a high quality of string in your inventory which prevents this from ever becoming an issue.
  8. Racquet abuse is another one on the list. No need to explain anything here. This is obviously not controlled by the stringer.
  9. Improper storage can wreak havoc with strings. By this we mean how the player cares for their racquet while in transit from one location to another. If they leave the racquet in the cab of the car or in the trunk in the middle of August the strings are going to be affected by the extreme temperatures. If pets and children can die from exposure like this it makes sense that the racquet strings aren’t going to do too well in the heat either. Also, think about the other extreme when traveling by air. It may be 80 degrees on the ground when your plane departs but once you reach 30,000 feet the temperature in the belly of that plane is much colder than you think. Don’t check your racquet with your luggage. If you’re going to take it with you make sure you include it as a piece of carry-on luggage.
  10. Stringer error — who me? Yes you. Stringers make mistakes because we’re human just like everyone else. Nicking the string or pulling the crosses too fast can damage the string. Trying to use an awl in a shared hole can damage the string but not break it at the time. After a few hits the string breaks and the player is wondering why it broke too soon.

About Strings

In the world of racquet sports it’s amazing to see how many players will be so concerned about what racquet they play with, going to great lengths to find that “perfect stick” for their game. Then, for reasons unknown to mankind, will give very little consideration as to the string or tension used. For the record, those of us in the business of racquet sports believe that the strings are to the racquet, what the engine is to a high performance race car. So here’s a little food for thought on the subject.

Listed below are 4 common materials that strings are made of:

  • Nylon
  • Natural gut
  • Zyex™(PEEK)
  • Kevlar™
  • Polyester

Nylon is basically what everyone refers to as synthetic gut. There are so many variations of this stuff out there today that a player can get confused just reading the list. Keep in mind however, that in the last 15-20 years there’s been a vast improvement in nylon string. If you’re a player that tends to follow the pack and you’re using synthetic string then you’re in good company. Over 90% of the players out there today are using synthetics.

Natural Gut is an entirely different animal-pun intended. It’s the standard by which all other high performance strings are measured. Made from beef intestines (no not cat gut) this stuff is the real deal.  Elasticity, when it comes to string  is a key factor. As of now nothing matches the elastic properties of natural gut! For years gut has been, and still remains, one of the overwhelming choices of touring pros that prefer maximum feel in the racquet. Think of it this way. If you spend the money for natural gut you’re probably going to keep it in the racquet much longer than your usual synthetic (man this stuff is expensive!) Eventually the gut will lose its playability and you’ll have to restring but during this process, you’ll soon see that your set of gut kept playing much better for a longer period of time than the cheaper nylon. Now imagine the player on the tour. These players are restringing before every match (the majority of them) and many are using natural gut. This means they’re getting maximum playability through their entire match-EVERY MATCH THEY PLAY! Natural gut offers unsurpassed “feel” of the ball and because of its natural texture, it tends to grab or cup the ball better than any other string. Another characteristic of natural gut that is often overlooked is the fact that it is more elastic at higher tensions, say between 55-70 lbs where most tennis racquets are strung. When string stretches at higher tensions natural gut is going to continue to stretch more, while a synthetic product will start to level off more as the load increases.

One last thing about gut. If you’re one of those unfortunate players suffering from tennis elbow, there’s nothing better than natural gut for your game and your arm.

ZYEX™ is an up and coming material that has been used for quite a few years but is just now hitting it’s stride.  Zyex based string exhibit high elongation and good durability.  The elongation of the Zyex based string makes this a possible alternative for players with arm problems that still require durability.

Kevlar™ is by far the most durable string out there but it’s also very stiff. Talk about lack of elasticity, this stuff is meant for one thing and one thing only-the string breaker. These days it’s always (or at least should be) used as a hybrid string where the kevlar is installed for the mains and the cross strings are a softer more elastic material to tame the kevlar down a bit. It’s suggested that you should reduce the tension by approximately 10% with kevlar but this is only a recommendation. Each player will have to find their own way if they plan to use this string.

Polyester is another very durable string that we’re seeing more and more of on the pro tour these days. However, keep in mind that poly loses its tension quicker than standard synthetics so adjust accordingly. Poly is also used as a hybrid for most recreational players but in many cases it’s used in the entire string bed on the pro tour. So why do so many pros use it if it loses tension so fast? Remember that most pros are restringing before every match. If you’re getting 2-4 hours of good play from the poly before it starts to lose tension pro players don’t have to worry about the tension loss. They’re usually restringing before they ever get to that point and if they get into a longer match, they can just switch to a racquet with a fresh string job.  As with many things it’s a personal choice and some players like that “dead” feeling that they get with kevlar or poly.


For the record, whoever invents a synthetic string that plays like gut and is as durable as kevlar is our hero! Until that day comes you’re stuck with two solid choices and several “in-betweens”. The two consistent ones are playability and durability. These two constants in the string will be determined by the strings composition, layup, and gauge.


Everybody wants it and if you want it badly enough you’re going to pay a premium price to get it. This means you’ll be buying natural gut because, as we said before, this is the standard by which all others are measured. Many strings in this category will be classified as “Multifilament”. This simply means that the string is made up of several (sometimes thousands) of twisted fibers. The technology used to manufacture these strings dictates that the costs are going to be higher. Here are some possible choices:

More expensive models-Multifilaments

  • Babolat Natural Gut
  • Bow Brand Natural Gut
  • Wilson Natural Gut
  • Gosen Remplir
  • Tecnifibre X One BiPhase
  • Technifibre NRG2
  • Wilson NXT Tour
  • Wilson NXT Max

Lower priced models-Solid core synthetics

  • Prince Synthetic Gut Original
  • Gosen OG Micro Series
  • Wilson Stamina
  • Babolat Synthetic Gut
  • Gamma Synthetic Gut
  • Tecnifibre Synthetic Gut


It’s no secret what’s going to happen for those of you who want more string life. If you want a more durable string you’re going to make sacrifices, primarily in playability and feel. You have several options ranging from a multitude of hybrid arrangements with poly or Kevlar or switching to a thicker gauge string. Remember however, when using a hybrid with stiffer mains with poly or Kevlar, or thicker gauge nylons that these strings are not as elastic as thinner nylons or natural gut and you’re sure to notice it. Here are a few choices in the durable category:

  • Luxilon Big Banger Original
  • Luxilon ALU Power
  • Ashaway MonoGut Pro ZX
  • Prince Pro Blend
  • Babolat RPM Blast
  • Babolat Pro Hurricane
  • Tecnifibre Red Code
  • Gosen Polylon
  • Gamma Monoblast
  • Kirschbaum Basic Poly

In the Middle

  • Gosen Sidewinder-this string is the first poly based string IART has tested that actually has significant elongation. The string is also textured to enhance spin. We can’t really place it in the durable category and it’s certainly not like a standard synthetic gut. Well worth a try in our opinion.

The important thing to remember is to restring on a regular basis. Your string’s tension will diminish over time and this will have an adverse effect on your racquets performance, which can translate into missed shots on the court. A new string job is a small price to pay to insure maximum performance from your racquet.

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