Category Archives: Tips
A Picture is Worth a 1000 Words?
Yesterday @ the World Headquarters was full of interesting stringing! So we decided to do some testing of some of the strings that were just waiting to be broken!
The chosen strings are Ashaway MonoGut ZX Pro 17, Tecnifibre Triax 17, and Volkl V-Star 18—three totally different materials. Our purpose is to determine a string’s properties before it goes into a tennis racquet. Our testing quantifies these properties, and then the “feel” component comes from the player.
A 1000 Words?
We normally do not do more than two (2) overlays because it is a little messy, but these strings begged to be compared, so here it is!
Our Questron can cycle automatically, so the stop points are pretty precise. All strings are cycled from two (2) pounds to fifty (50) pounds and then until they fail or ultimate tensile strength (UTS).
In the Displacement axis (X), the shorter the distance in mm to 50 ponds, the stiffer the string. The straighter the line is to fail, the more consistent the feeling until failure.
The testing confirms that Tecnifibre Triax does contain some stiffer fibers. The other strings are monofilaments, so there are no fibers.
Racquet Quest uses a bunch of each of these strings for obvious reasons and, of course, depending on the player.
Pre-Stretching String…Why and How?
Every string we put into a tennis racquet is “pre-stretched”…not just sometimes but every time! This is an old post but worth seeing again I believe.
Why?
Pre-Stretching slows down the “creep” process that reduces string bed stiffness, (tension loss) and to feel what the string is doing while being stretched, and making some strings easier to handle during the stringing process. Some strings stretch a lot and some strings don’t. We can tell a lot about how the string should be handled (and the application) based on pre-stretching.
How?
Most stringing machines have a pre-stretch feature, including ours, however, we prefer the entire length method. All forty (40) feet of it! If you have a room, that is forty feet long, or a perfect outdoor spot use it!
The proper tools and proper technique make pre-stretching an easy and performance-enhancing procedure.
Parallel Plier
The object is to pull the string straight. The plier needs to grab the string as shown.
The arm and wrist should be in the neutral position as shown so the stress is on the string, not your body.
The other end of the string can be secured through a hole with a “starting clamp” as you will see below. These clamps are rated to hold 90 pounds so it is not in danger of letting loose!
Tree Hole
We probably hold the string at tension for 30 to 40 seconds after applying four or five quick short stretches.
For many years we used a high-tech device to measure how much force we apply during the stretching procedure. The force we apply is between 35 and 40 pounds using this rig…
This scale is rated to 100 pounds. The string is inserted through a hole in the bracket and secured by a starting clamp, then using two hands grab the handle and begin to stretch the string while reading the force on the scale. After using this device for a while it will become a matter of “feeling” not measuring the force.
Stretch Scale
String Shape
How’s the shape of your string?
Is it round, square, hexagonal, octagonal, triangular, or something else?
The string pictured here is square. The dimension across the flat sides is roughly .048 inches/1.22mm, which means the largest dimension is about .063 inches/1.6mm but due to the rounded edges it is less than that. The wear is happening on the “flat” side (.048/1.22),
A flat-sided string shape can create some issues when trying to achieve consistent string tension.
Side View of Fail
Flat Side Wear
String Bed View
This is expected because the string will want to align with the flat side, not the edges. This may cause the string to twist and create added friction when tensioning.
So, we can expect the “edges” to be exposed to the ball, and the “edges can create friction on the ball, which causes rotation!
Yea! How much and for how long is hard to know.
I believe it is safe to say “square” is a good “shape” for your string to be in for polyester monofilaments which we are looking at here.
Our Questron in Action!
As you know, Racquet Quest is a data-driven business, and data requires numbers. To generate those numbers, we have designed and built several devices.
One device is the Questron!
The Questron is used to test every string we receive, and the data is compiled to understand where that particular string fits.
So, instead of talking about it we have included a short video!
Thank you for watching our Questron in Action! If you have a question, or a particular string of interest, please let us know. We may have already taken the data! On GASP.network there are many graphs of previous tests. GASP.network is a membership ($40.00 one time) site.
Racquet Quest, LLC
