Category Archives: Testing Devices
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.
What Can Pictures Tell Us About String?
It is said that “a picture is worth a thousand words,” which may be true as long as the picture tells a story.
This story is about natural gut string, and the pictures will show what we can achieve, informationally, with our testing equipment. The two (2) strings are Babolat VS Touch 17 and Luxilon Natural Gut 125.
Our Questron software scales the images to suit the data so the graphs will not be the same size.
Our testing loads the string from 0 pounds force to 50 pounds and back to zero then up to 50 pounds three (3) times. This is the “stress/strain” curve. Fifty (50) pounds is arbitrary and because we are using the same methodology for all string materials it is a good number. The closer these lines are together the better.
The farther it takes to reach 50 pounds the “higher elongation” the string is. In this case it is about 44mm.
The important property of this string is the linearity! That is the “straightness” of the line from beginning to end. This indicates predictability, stability, and consistency.
This picture tells us the tensile strength and the knot strength. In this case the knot strength is 52.3 pounds and takes a stretch to very close to 60mm before failure.
What is, probably, the first thing you notice about this “picture”? Could it be the squiggly lines? What could be causing this?
We believe it is the “break-in period” players associate with Luxilon gut! We have heard it from the players but have not been able to “see” it! It could be the bonding agents realigning as the load is applied.
You will notice a couple of things: the similarity of the “stress/strain” curve and the displacement to “knot strength” of the two strings. This string will feel a little less “soft” than the Babolat VS Touch 17. The linearity is quite good up to failure.
So, based on these pictures, could you make a recommendation? If so, let us hear them!
The World Headquarters of Racquet Quest, LLC was happy to welcome Randy St. Pierre and Henry Hamels for a visit!
Randy is a member of the Dunlop Stringing Team and is from the UK and Henry is the principal of String MD in Florida! Randy has been stringing racquets for quite a while and is always a source of good information…and he bought lunch!
Randy lives in a beautiful part of England so we are all invited to his house when the weather is better…is that right Randy?
Randy remembers stringing for a young player named Emma at a tournament in Nottingham when young Emma was in the 300’s world wide! Look at her now! Was it Randy or something else? I wonder!
Anyway it was great fun having these guys here and they are welcome anytime as are all of you reading this!
And the winner is…Head FXP 17
Head FXP is a string that seems to be largely overlooked and I am surprised after seeing the results of the installation and testing!
|String Name||Category||Gauge||Ultimate Tensile Strength/Lbs||Knot Strength/Lbs||Country of Origin|
|Head FXP||Multifilament - Nylon||17||165.9||93.4||Japan|
Both the tensile strength and knot strength are exceptional and the graph shows that this string is very “elastic” which is a good thing for tennis racquet string but sometimes just not considered.
The area under the solid red lines is considered a stress-strain curve and indicates the “elasticity” of string by how close the lines fit from 0 to 50 three (3) times. A perfectly elastic material would be one line even though it went through three (3) cycles. What you see here is quite good and one of the reasons it is the winner!
String Evaluation Program
Racquet Quest, LLC has for years been doing the extensive evaluation of racquets and string for the benefit of our client’s customization requirements.
Now we are making this evaluation “program” available to anyone that wants to dig deeper into the workings of the string in the racquet!
This is serious stuff and requires significant resources but it is worth it!
Please contact us of you would like to take advantage of our evaluation program!