Category Archives: Natural Gut String

Play Better Longer

For many years, we have been testing all racquets for string bed stiffness, effective stiffness, flexural stiffness,  in-plane stiffness, and about any other stiffness you can imagine.

Throughout this process, we were also testing the strings for power potential, creep, string-on-string friction, and linearity.

Linearity is a significant property of string; however, it does not get the attention we believe it deserves.  So, this little post will begin to change that.  We will start with some images and explain what we see in them.

String Behavior

Four different string materials are represented here from left to right:

  • RPM Blast
  • IsoSpeed Polypropylene Composite
  • Babolat VS Touch Natrual Gut
  • Ashaway MonoGut ZX Polyether ether ketone (PEEK)

The entire chart is important, but the real property we are interested in for this post is “linearity”.

  • Linearity is how straight the plot is from the beginning to failure.
  • Failure is the vertical line associated with each string material.

A glance will show MonoGut ZX with the longest linear track, however, Babolat VS Touch is the very “straightest”, followed by IsoSpeed and RPM Blast.

OK, but why do we care?  We care because when we say a string will play better longer, it is based on the linearity which is the property directly related to consistency.

Better predictability = better performance
Players perceive predictability more than raw stiffness.
A string that ages predictably plays better longer, even if it’s not the softest or most powerful.

That’s it!

Now all we need to do is quantify “better”.

I will leave that up to you.

 

 

What About Me?

A lifetime dedicated to racquet technology and innovation

For more than five decades, I have been immersed in the world of tennis racquet and string design, manufacturing, and performance optimization. As the owner of Racquet Quest, LLC, I’ve combined deep technical expertise with hands-on innovation to set new benchmarks in racquet customization, diagnostics, and stringing.

My journey has been defined by a relentless pursuit of precision and performance—whether with professionals, college,  junior tournament players, in the lab, or in front of an audience, sharing knowledge with peers.

Advanced diagnostic technology

At Racquet Quest, technology and science drive results. I’ve integrated some of the most advanced diagnostic equipment available, alongside proprietary systems I’ve developed, to provide unmatched insights into racquet and string performance:

  • True Tension Stringing Machines – pioneering distortion-free stringing
  • Babolat Racket Station & Wilson Baiardo Stringing Machines – industry-leading accuracy
  • Babolat RDC (Racquet Diagnostic Center) – comprehensive racquet analysis
  • Questron proprietary string testing equipment – measuring ultimate tensile strength, stress/strain, knot strength, and more
    • Three-string comparative graphing tools – side-by-side performance visualization
    • Flex, In-Plane, and String Bed Stiffness devices – quantifying structural dynamics
    • Custom portable SBS device – portable precision testing

By combining these tools, I’ve been able to capture and refine the delicate balance between tension, elasticity, and structural integrity, pushing racquet performance beyond traditional standards.

Innovation in design and customization

Innovation has always been central to my work. Some of the highlights include:

  • Development of the Perfect Pallet grip system with a custom three-piece anti-vibration design
  • Expertise in Special MakeUp (SMU/Pro Stock) racquets for elite players
  • Custom racquet extensions and modifications tailored to individual needs
  • Proprietary software solutions for collecting and analyzing racquet and string performance data

These advancements have helped players—from juniors to professionals—experience greater consistency, comfort, and control on court.

Experience on the global stage

  • My expertise extends well beyond the workshop:
    • 50 years in racquet and string design and manufacturing
    • Professional event stringing services for several years at major tournaments
    • Seminar presenter for 12+ years, sharing expertise with players, coaches, and technicians
    • Delivered the acclaimed session “Understanding String” at the 1994 Super Show in Atlanta, hosted by the United States Racquet Stringers Association

This combination of hands-on service and educational leadership has helped shape best practices across the racquet service community.

Media and knowledge sharing

I believe that expertise should be shared widely. To that end, I’ve created multiple platforms to bring racquet knowledge to players and enthusiasts worldwide:

  • RacquetQuest.tennis – a hub for insights and resources on racquet technology
  • Racquet Quest Podcast, Podcastini, and Podcast Midi – covering everything from string science to on-court trends

Through these channels, I aim to make the science of racquets accessible to every level of the game.

Tennis continues to evolve, and so does racquet technology. At Racquet Quest, I remain committed to research, testing, and innovation that give players an edge while deepening their understanding of how equipment shapes performance.

Whether stringing for professionals, customizing for serious competitors, or educating the next generation of racquet technicians, the mission remains the same: deliver precision, performance, and passion through technology.

Questron Cycle Update

Every string that enters the World Headquarters of Racquet Quest goes through the Questron cycle.  We have posted images of the product of the cycle, but not the entire process that the Questron goes through to create these posts.

The following video is the entire process from start to post.  We look forward to your comments!

If you have a string, or strings, that you would like to know more about, please let us know.  We may have already put them through the Questron Cycle.

I mistakenly said “Z” axis when I meant “X” axis, if you caught it.

Head Auxetic 2 Radical Pro SMU

Three (3) beautiful Head Auxetic Radical Pro’s off to South Florida!

Head Auxetic 2 Radical Pro SMU

Head Auxetic Radical Pro 28

 

These racquets represent a full custom version.

These racquets are 28 inches long (71cm) with a swing weight of 336 kg/cm^2.

The grip pallet is TK82S and the grip material is Head Calf Skin.

The string is Luxilon Natural Gut 130.

 

ManufacturerNordicdots
Racquet ModelModel 99
Reference Tension46
String
MonoGut ZX Pro Black
Machine UsedTrue Tension Pro
Static
String Bed Stiffness - RDC43
String Bed Stiffness -FlexFour52.9
Strig Bed Stiffness - SBS44.7
String Bed Stiffness - ERT30
Racquet Flex, RDC62
Racquet Flex, FlexFour38.3
Racquet - In Plane Stiffness423
Weight, Grams325
Weight, Ounces11.46
Balance, mm323
Balance, Inch12.72
Length, Cm68.6
Length, Inch27.0
Head Width9.59
Head Length12.904
Head Area, cm2614.8
Head Area, Sq. Inch95.3
Beam Height @ Grip, mm23.8
Beam Height @ Mid, mm23.2
Beam Height @ Tip23.2
Beam Width @ Grip, mm11.5
Beam Width @ Throat, mm10.5
Beam Width @ Mid, mm10.5
Beam Width @ Tip, mm12.9
Number of Main Strings16
Number of Cross Strings20
Ratio.583
Main String Grid Inch/mm7.31/185.6
Cross String Grid Inch/mm9.93/252.2
Density (% of head filled with string).762
Average Cross String Space.497
Average Main String Space.457
Dynamic
Dynamic Tension, Kp, ERT30
Dynamic Tension, Lbs/in167.8
First Moment, Nm.807
Polar Moment337
Torsional Stability16
Swing Weight, Kg/cm^2321
Swing Weight, Ounces11.32
Swing Weight Calculated339.1
Power, RDC51
Control, RDC47
Manueverability, RDC73
Power, Calculated 1915.4
Head Points6.30
Head Weight, %47%
Center of Percussion21.37
Dwell Time, ms7.14
Efective Stiffness - lbs25.39
K, Lb/In137.82
Recoil Weight161.7
Twist Weight216.1
End Weight 132.7
Tip Weight 191.2
9 O'Clock90.6
3 O'Clock90.6
Butt End143.5
COF, Main.358
COF, Cross.311