Category Archives: Learning

Recommended Stringing Frequency (RSF)

We have moved the very popular Recommended Stringing Frequency (RSF) spreadsheet to the main body of our web page to make it easy for you to determine when to re-string your tennis racquet.  This recommendation is based on the very best overall performance of your racquet.  

You can use this valuable tool to evaluate a tennis racquet purchase.  If you are considering a new racquet insert those values and compare it to what you are currently using to see if your stringing frequency will be similar.

This is an interactive spreadsheet so all you need to do is put your racquet values into the fields below “Your Input” heading. The rest is calculated for you.  Don’t worry if you do not have a UTR number.  By putting a “0” in that field a value will be added for you.

In “Player Style” you can enter, “tour, club, beg, rec” and a value will be inserted for you. If you are a junior tournament player please use “tour” in this field.

It is not necessary to put a value in both the “UTR” and “Player Style” fields, just one will do.

Use “return” to move on to the next field.

The “Value/Playability Ratio”  incorporates a factor to quantify the value, or enjoyment, of each type of string.

In the “Stringing Date” box near the bottom you can enter the date your racquet was strung and your “Next Stringing” date will be calculated for you.

We hope you enjoy this update!  Go ahead, start now!

Let’s Talk About This!

I decided to write about this again after reading some posts asking questions, good ones by the way, about string tensions when stringing a racquet.

What we are discussing is not a simple matter, in fact, it is challenging to quantify many things we believe are real.  It is difficult, if not impossible, to tell a stringer how to string a racquet for a new client.  These are the obvious player/stringer questions that need to be answered:
a. What racquet type?
b. What string type?
c. What main and cross string tensions should be pulled?
d. What stringbed (SBS) stiffness is wanted?
e. What racquet weight, swing weight, and CG is wanted?
f. What stringing machine should be used (yes this matters, but is rarely considered!)?

There are also many player-specific questions that are in the mix, including:
a. Do you want more or less power?
b. Do you want more or less control for that power?
c. Do you want to hit with more spin?
d. Do you have any physical problems influencing your play (sore shoulder/arm, elbow, strength, etc.)?

The task/responsibility for a good stringer, or, racquet technician preferably, to his player is quite daunting if the goal is to “string responsibly.”

With answers to these questions, and a stringers plan in place to achieve these goals, one of the most important attributes a stringer can deliver is repeatability. Once a player has settled on a path (racquet, strings, tensions, stringbed stiffness (SBS), etc. you want, as a client and stringer, that customized performance to repeat with every re-stringing. So the stringer must have a process, with metrics, that will guarantee that repeatability. This repeatability is also the foundation for changes from that norm (for example, what happens if I replace my strings with another type, or if I stay with the same strings but switch racquets, etc.)

My comments that follow is the plan I have developed for my stringing process for the players I try to support.

One of the most important influences on how a racquet plays is the stringing machine that is used to string a racquet.

About twenty years ago I developed a machine evaluation procedure for understanding what happens during, and after, the stringing process.

Every machine is treated in the same way. The same racquet, the same string, and the same tension settings, and the same testing devices. I am not going into detail here because it is quite a lengthy path.

Here is what we need to know:
1. When stringing a racquet with main and cross strings, every racquet has a “natural ratio” of the final cross tensions to the final main tensions. That is what the cross string tension is relative to the main string tension of a finished racquet.
2. Nearly every machine tested allowed considerable distortion of the racquet in the three and nine directions. As much as .380 (9.62mm)! You want to minimize that distortion for the final strung racquet.
3. Almost every machine reacted slightly differently when the racquet was removed, i.e., some easier than others.

Why does this matter:
1. Due to the distortion, with the racquet in the machine, every machine produced main string only tensions of about 55% of the machine tension setting. That is the machine is set on 60 for example, and the measured tension is approximately 33 in the middle and increasing slightly going toward the 5th and 6th string. It never reaches 60 with only the main strings installed.

2. When the cross strings are installed, they begin to pull the racquet head back into shape but not significantly until nearing the 11th or 12th cross string.

3. When the racquet is finished and depending a little on the number of strings, it will, hopefully, return to close to the original unstrung shape and dimensions.

4. This “reshaping” can have damaging effects (stress failures) on the racquet.

Here is the question that started this whole discussion again.”

So, do I want to increase or decrease cross string tensions? My opinion is that until you know how the racquet, any racquet, is going to react don’t change tension settings at all. The key here is a responsible stringer wants repeatable metrics first.

We have an “Accuracy Index” procedure for every string pattern, that is the number of main strings and number of cross strings, that calculates the accuracy of the entire string bed based on where the ball is impacting the string bed. The accuracy index is a measure of the ball rebounding normally to a deflected string bed. For example, if a ball were to hit in the geometric center of an elliptical head racquet that was strung with main and cross string tensions that minimized racquet stresses and frame distortion the accuracy index would be 1.0. For the same racquet, if some of the strings were at low tensions (perhaps a break) the accuracy index would be less than 1.0.

Based on “observed breakage locations” we can see the accuracy of that small area of the string bed where most breaks occur.

Most machines I have evaluated will return accuracy indices of 87 to 95 percent.

I have, however, included in this test an “Efficiency Index” which shows me how much the racquet had to “move around” to achieve the accuracy index number and reach some equilibrium. This value is typically in the 70 to 75 percent range! So the racquet is working hard to get back into shape.

If you are a stringer or racquet technician, please note that after the racquet is setup in the stringing machine properly do not make adjustments to the supports during the stringing process. In some cases, the supports will not be in contact with the racquet. Don’t adjust.

Unless the racquet is mounted on a solid annular plate, like the top image, do not restrict the expansion of the racquet by placing a restrictive member across the 3 and 9 o/clock positions which in this image are the top and bottom.  The red knobs are the 12 and 6 o’clock positions

True Tension Professional

True Tension Professional Machine


Wilson Baiardo

Yonex Protech 8 Contact Points

Babolat Racquet Station

Need Direction?

A client just sent me the following statement and I think it has reason to be distributed amongst tennis players searching for “direction” when it comes to string and their game!

“Hah. Trying out these different strings has been very interesting. Over the past week or so, trying the different strings has given me some insight into what my game should be. I think usually people do it in reverse. They try to find the string that tailors to their game. By experimenting with the strings, I realize the direction my game should be going.”

“I’ve been coming to realize that my game is better with control and feel rather than power.  Experimenting with different strings have helped me recognize this.”

Do you think this applies to you?

Get real!

A lot of players are anxious for new tennis racquets this time of year and have, maybe, asked for one as a gift.  A great idea, of course.

However, be sure the gift giver, or yourself, gets real!  There are some real bargains out there, but the bargains may not get you what you expect.  This can happen to any brand and the more popular the racquet, the more likely there are to be fakes!

Fake Blade 98

This is an image of a fake Wilson Blade 98 compared to a real Wilson Blade 98.

I am showing this image because without seeing this detail the fake racquet graphics will look nearly identical to the real Wilson racquet.

One of the best ways to confirm a fake or real racquet is to “bend” it, that is to check the stiffness of the racquet.  In almost every case the fake will be quite a bit more flexible.  For example, this fake racquet has a stiffness of RDC 41 whereas the real racquet has a stiffness of RDC 63.   If your racquet technician does not have a device for checking stiffness the next best thing is to look at the “insides.”  A qualified racquet technician will know what the insides of the real racquet look like.

Another sign of fakery is the grip pallet.  Most performance racquets will have a foam pallet molded over the graphite shaft or a two-piece pallet that is attached to the racquet shaft.

Fake racquets may very likely have a continuous graphite pallet.  You can quickly look under the first couple of inches of the grip and see if it is foam or graphite.

Clamshell grip pallet

If you are requesting a new tennis racquet be sure you get it from a local business, if possible, or an otherwise reputable source.

If you have any questions at all, please call your local dealer or us (407.491.4755) to be sure you “GET REAL.”

Why Sell Tennis Racquets?

With a zillion or more places to buy tennis racquets, why would Racquet Quest, LLC want to to do it?

Simple. Racquet Quest, LLC offers a level of racquet preparation that just can’t be matched by an online or big box seller of the same equipment!

Racquet Quest, LLC sells only a few brands of high-quality tennis racquets, so it is reasonable to look online for the racquet we do not carry. We can assist you in making the right decision wherever you decide to buy.

But, please take your new racquet to a local, and hopefully qualified racquet technician for stringing!

“But, dude, what about the free stringing I am getting online?” The value of “free” is not very high, so please consider the following post I made a long time ago:

So, the answer to the question is “we sell tennis racquets, so you get the very best performance from that racquet from the very beginning!”

We take tennis racquets very seriously, and we suspect that you do too so get it right!


Shaped String Considerations

Monofilament string can be easily produced in almost any shape.  Round, square, triangular, hexagonal, octagonal etc.  So, on the surface that seems like a good thing.  Who wouldn’t want the sharp edges digging into the ball creating even more spin!

But, there may be a side to the shape that needs considering and that is tension as it is applied to the string vs tension as it is in the racquet.  Those can be two very different things!

When the main strings (the long ones usually) are installed they are free to move and will normally be only slightly “twisted”.  This is more obvious with square and triangular strings.

Cross String Twist

This image shows one of the lower cross strings and the “twist” is obvious.  So what?

So the tension on these strings will be considerably lower than expected.

Why?  The machine tension head is set to pull each string to the desired setting, say 50 pounds.  When the machine “feels” 50 pounds the tension head stops.  The cross string will twist, just like a screw, as it passes over and under the main string.  A twisted string will not pull through the adjacent main strings easily so the tension will, in this area, be less than desired.

This variation in “tension” can affect the way a ball comes off the racquet.

We use string spreading devices for every racquet and every type and shape of string.  The “spreaders” raise and lower the main strings so there is no friction (twisting) between the cross string and the main string.

Not all racquet technicians use this type of device, so,  the twisting can be mitigated by weaving the appropriate cross stings over and under the main string one at a time making sure they are not twisted and then apply the machine tension.  This will result in a more consistent result.

If your racquet has cross strings that look like the image be sure to mention it to the stringer so it can be remedied.


What is Important?

I spend hours each day dealing with tennis racquets, strings, machines and questions of all sorts!

By doing this I am learning what is important to tennis players but it should not require a one-on-one discussion to learn this, in my opinion.

So, what is important to you?  Here is what I am discovering.

Comfort.  It goes without saying that you don’t want to play tennis if you are hurting!  Players are requesting racquets that are more arm friendly.  But wait, the racquet really holds the string which has a huge impact on comfort.  So should we begin with string?  I think so!

String.  Every string I have has undergone a comprehensive testing procedure to determine elongation which in turn is converted to Power Potential.  The higher the elongation the higher the power potential and the less stiff the string bed will feel when the ball is hit hard, all other settings being equal.  If you have a stiff racquet it is important to select a string and tension that will mitigate the racquet stiffness to some extent.  Every racquet we do has the “effective stiffness” calculated which is the combined stiffness of the racquet and string bed. Once we have the preferred effective stiffness for a customer we can achieve that even if a new racquet is added to the mix.

Durability.  We try to associate the cost of racquet stringing to “cost per hour” of play time.  What is your threshold?  $1.00 per hour or $10.00 per hour?  When considering durability do not confuse “performance” with “durability”!  There are several strings that may not fail for several months however the performance is gone in a few hours.  This is typical of polyester based strings.  So, even if the string is still intact the performance is way gone!

Cost.  The cost of tennis racquets is increasing, sometimes justified, sometimes not but are rising none the less.  If cost is your “driver” some navigation around the market is important, however, we do not suggest you buy the “cheapest” thing you can find without a thorough understanding of what you are getting.  We can assist you in evaluating racquets from any source.

Catching up!

The past month has been a whirlwind of weather and other activity and I wanted to pass on some recent news.

The USRSA World Conference was held at USTA National Campus, however in the brand new USPTA National Headquarters! What a perfect building! Several session leaders from around the world presented terrific sessions on topics necessary for racquet technicians. I presented a session on “Customization.”

USRSA World Conference, Orlando, FL

Being near the USTA Campus was perfect for grabbing a fabulous and quick lunch. Try the fresh pasta the next time you are there!

This month the World Headquarters welcomed Ron Rocchi, the Advanced Innovation Manager at Wilson, and Eric Ferrazzi, Stringing Machine and Tour Stringing Manager for Babolat, France. These guys are the pinnacle of the field, and I am always glad to have them here.

The new Babolat Racquet Station is in and being used and evaluated. This is one of the most significant “electronic” upgrades you can imagine!


Some new and essentially “secret” racquets are in and being reviewed.  The non-secret ones will be in around the 8th of November!

Hybrid Stringing…What is it and Does it Matter?

When the discussion is about stiff polyester string, it will always include the word “hybrid”!  Typically this word is used to convince players that by putting a “soft” multi-filament string in the cross position the string bed will be easier on the wrist, elbow, and shoulder.

Intuitively this makes sense, but in reality, the reverse could be true!

I began analyzing hybrid string beds years ago and did many just to test the theory. At the time it did not seem so important because, frankly, the use of polyester based string did not approach the usage of current times.

I have nothing against the polyester string(s)! I do have an issue with bad applications of polyester string(s).

I am bringing this up again because recently an “interviewee” stated that that replacing the polyester cross string with a multi-filament would cure the ills of a very stiff string bed.

The bottom line:

A high elongation string of any material can increase the string bed stiffness of a hybrid string bed!

How can this be?

Stiff (polyester) strings are “stiff” and the tension applied to them during stringing is low. However, high elongation (multi-filament) strings will be influenced more by tension and become “stiffer”.  The cross stings are typically shorter, and there are more of them, so the combined affect is stiffness.

The initial reaction to this conundrum is to automatically reduce tension on the cross string by a certain amount. Again this raises another issue, and that is racquet distortion.

During the installation of the main strings most stringing machines will allow the racquet to become wider, sometimes a lot wider! So, reducing the cross string tension may not return the racquet to the designed shape. What happens then is the racquet will continue to move around trying to find a “safe” place and therefore the string bed stiffness changes.

In summary, the hybrid string bed will not be statistically different than the full string bed of polyester. This is even truer if the initial string tensions of the polyester are very low, such as 35 to 40 pounds.

So if you feel the need to use polyester just go with lower, lower,  tensions.



Is It Worth It?

Racquet Quest sells only a few high performance racquet brands so it is not unusual for us to receive racquets purchased from on-line sources.  These can be dropped shipped to us or brought in by the client.

That’s great.  But here is the problem!

If you have a racquet technician in your neighborhood do not have the racquets strung by the online source!  Take the racquet(s) to someone you trust, and, can be there if there is ever an issue, and this is an issue!  The knot actually came untied!  This is rare but is particularly likely when using a really “cheap” string and not knowing how to tie a proper knot!

Two things are happening here.  The knot on the top is a “tie off” knot.  While the tail may become loose it is not likely the knot will totally untie itself.  The knot on the bottom is a “starting knot” and was subjected to the tension of the first cross string and, as you see, became a “not knot”.

Very Close to a Not Knot!

Very Close to a Not Knot!

"Not A Knot"! Whoops!

“Not A Knot”! Whoops!

This was very likely a “free” or “discounted” stringing so why not take advantage of the offer!

In this case, it is impossible to play with the racquet so what was saved by the cheap stringing?

This happens because the source knows that the racquet will probably not be returned for correcting the error(s) so who cares!

I care and you should care!

That is my “rant” for the day!

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