Category Archives: Bad Stringing
Use Your String
We want you to play your best, and using your string is a component of your performance.
If you have any questions about your string and the best stringing technique, please let us know. We can provide information that may help the tournament stringing team meet your expectations.
What is wrong with this picture?
Actually, it is going to be two (2) pictures! One with no narrative and one with an explanation of what is wrong!
Did you see what was wrong with this picture? If you did, congratulations are in order!
If you didn’t know what was wrong with this picture, here it is! If you receive a freshly strung racquet that looks like this, take a close look at the strings and do not accept it if there is a “mis-weave” in the string bed!
Sometimes this condition is not easy to spot, so take a good look.
SBS…what is it and why should we care?
We have made several posts regarding SBS, which is “String Bed Stiffness” and this is another one!
If you read this post we really need your comment(s), really!
String bed stiffness is the “feeling” when the ball hits the string on a tennis racquet. Due to the various string materials there will be “soft” and “hard” feelings. But wait, there’s more!
The string bed is made up of several strings, some longer called the Main string (M)and some shorter called the Cross string(X). Using “reference” tension each of the sets of string will be pulled at the same machine setting! It the machine is set at 50 pounds the tension head will stop pulling when it feels 50 pounds of resistance, regardless of what he tension inside the racquet head may be.
Let’s say you come into the world headquarters and we ask you what SBS you would like to have? Would you know? Probably not and not many would! We have grown up using the term “reference tension”, not SBS.
Reference tension is “number” you would ask your racquet technician to set the stringing machine tension system on. That number will probably be between 30 and 60 pounds (≈13 to 26 Kilo).
So, depending on many other variables, such as string material, string pattern, stringing machine, stringer technique, etc., you can end up with may different versions of the same “reference tension”.
A better way, and one we have been using for over thirty (30) years, is SBS but not everyone has bought into the concept, even though a qualified racquet technician will have a way to measure SBS! Maybe because it is too much trouble to figure out what your desired SBS from machine X would be from machine A! It is not!
There have been several really good SBS data collection devices but they have been difficult to use, and pricy! Not to mention gigantic!
Would you purchase a SBS data collection device?
How much would you pay for such a device?
Would you prefer a mechanical device or an electronic device?
The device must be portable, that is easily carried in a racquet bag or backpack
Yes or It doesn’t matter
It must be easy to use.
If you use an SBS device would you use a racquet technician that did not know what SBS is or how to measure it?
Thank you for adding your comments to this discussion! It is important stuff!
What Can String Failure Tell Us – Part Deux
In Part Un we discussed the difference between shanking (mis-hit) and friction failure. It was obvious that the string was broken. But what happens when it is not so obvious?
Part Deux, this part, will examine the frictional notching failure of monofilament string and how we can be prepared for it! To further refine this discussion we will be comparing PET polyester has PEEK monofilament string. The reason is that each material while both will notch one requires more time to reach the critical dimensional decrease that is a failure!
In almost every Racquet Quest Podcast we talk about tension v string diameter and agree that once 50% of the string diameter is notched away the string is vulnerable! So a .050 (1.27mm) diameter string that has a tensile strength of 120 pounds at 50% notching will have 60 pounds of tensile strength remaining.
Notched v un notched string
This graph is a string that was broken during use. The string was removed from the racquet. The top line is the tensile strength in the area of no notching so you can see that it is pretty strong still and has stabilized due to use. That stabilization is indicated by the very tight stress/strain grouping.
However, things go sideways when the notched area of the string is put under stress. The string failed at a force of 63.8 pounds, or about 59% of the used tensile strength. Not bad!
So, notching is failure-inducing but how long it takes to create the fatal notch differs with string material. This particular set of strings had about six (6) hours of play.
In Part Trois, we will look at PEEK material under the same conditions!
Racquet Quest, LLC
