Category Archives: PEEK
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. Â 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.
Head TK293.1 XL Retro Review
Head TK293.1
This is the selection of “retro” racquets that will be included in our “Retro Review” series.
The following data is based on the XL version disguised as the “Auxetic” model. I imagine Auxetic was just a dream when these racquets were made.
While we are on Head Prestige racquets, I am surprised that more players avoid this series!
Especially now with the new Prestige MPL added to the mix.
| Manufacturer | Head |
|---|---|
| Racquet Model | Head TK293.1 XL |
| Reference Tension | 54 |
| String | |
| Machine Used | True Tension Pro |
| String Pattern | 16x19 |
| String Bed Stiffness - RDC | 52 |
| String Bed Stiffness -FlexFour | 59.1 |
| String Bed Stiffness - SBS | 46 |
| String Bed Stiffness - ERT | 34 |
| Racquet Flex, RDC | 64 |
| Racquet Flex, FlexFour | 46 |
| Racquet - In Plane Stiffness | 434.6 |
| Effective Stiffness | 28.7 |
| Weight, Grams | 335 |
| Weight, Ounces | 11.82 |
| Balance, mm | 328 |
| Balance, Inch | 12.91 |
| Length, Cm | 69.8 |
| Length, Inch | 27.48 |
| COP (inches from end) | 21.7 |
| Head Width | 9.44 |
| Head Length | 12.82 |
| Head Area, cm2 | 613.1 |
| Head Area, Sq. Inch | 95.0 |
| Beam Height @ Grip, mm | 22.5 |
| Beam Height @ Mid, mm | 20.4 |
| Beam Height @ Tip | 20.3 |
| Beam Width @ Grip, mm | 10.6 |
| Beam Width @ Throat, mm | 10.3 |
| Beam Width @ Mid, mm | 11.4 |
| Beam Width @ Tip, mm | 11.3 |
| Number of Main Strings | 16 |
| Number of Cross Strings | 19 |
| Ratio | .620 |
| Main String Grid Inch/mm | 7.25/184.1 |
| Cross String Grid Inch/mm | 9.06/230.1 |
| Density (% of head filled with string) | .687 |
| Average Cross String Space | .477 |
| Average Main String Space | .451 |
| Dynamic Tension, Kp, ERT | 34 |
| Dynamic Tension, Lbs/in | 190.2 |
| First Moment, Nm | .848 |
| Polar Moment | 358 |
| Torsional Stability | 13 |
| Swing Weight, Kg/cm2 | 345 |
| Swing Weight, Ounces | 12.17 |
| Swing Weight Calculated | 360.4 |
| Power, RDC | 54 |
| Control, RDC | 47 |
| Manueverability, RDC | 58 |
| Power, Calculated | 2182.2 |
| Head Points | 6.61 |
| Head Weight, % | 47.0% |
| Dwell Time, ms | 6.49 ms |
| K, Lb/In | 166.7 |
| Recoil Weight | 173.29 |
| Twist Weight | 224.33 |
| End Weight | 132.2 |
| Tip Weight | 202.3 |
| 9 O'Clock | 95.6 |
| 3 O'Clock | 94.8 |
| Butt Cap | 145.2 |
| COF, Main | .484 |
| COF, Cross | .332 |
Monofilament Material Comparison
Most monofilament tennis strings are polyester, a blend of polyester, or PEEK.
As you know, we believe there is no wrong string, just wrong applications. Â The graph will show the comparative stiffness of three (3) materials. Â The string is pulled at a rate of 1mm per second. Â The resultant spreadsheet for this particular test is about 5300 rows long.
With our spreadsheet, we have access to every mm of data. Â Maybe sometime we can post some of the individual data points.
Blast is polyester, V-Star is a unique blend of material (I do not know what it is), and MonogutZX is PEEK (polyetheretherketone).
The graph shows the cycle from 0 to 50 pounds three (3) times, then to failure (UTS). Â The quicker (shorter distance) the string reaches the 50-pound mark, the stiffer it is. Â MonoGut ZX did not fail in the 180mm excursion. Â You can see, in this case, the stiffer string fails at a higher force but shorter excursion.
Stiffer strings deliver less power and have a higher shock value. Â The midrange stiffness shows exactly what would be expected, and the softest string also indicates expected results.
Lets compare the Head Prestige Pro 16×19 v Head Prestige Pro 18×20
The following graphic will show clearly why the pro stock (SMU) racquets are very important in our quest to enhance the performance of all players!
A primary reason we work with custom racquets is the length of the racquet as we receive it, which allows us to create up to 28 inches (71cm) long. Â We can extend racquets however reducing the length is the preferred option.Â
Of course, we can customize the SMU to match the specifications of the retail (27-inch) racquet but with a 16×19 string pattern.Â
If you look closely you will recognize the tremendous possibilities beginning with a lighter, more flexible racquet for players of all physical abilities!
The supply of the 16×19 racquets is limited, however, demos are available for both.
Head Prestige Pro 18×20 2023 Retail
This Head Prestige Pro 18×23 Retail version offers a high performance racquet ready for serious play! Â However, we offer the custom version for players who prefer a slightly more open string pattern and some customization.
As you will see on the specifications, this racquet is serious, but most players can use this racquet if they get over the idea that these are stiff racquets!
| Manufacturer | Head |
|---|---|
| Racquet Model | Head Prestige Pro 2023 18x20 Retail |
| Reference Tension | 52 |
| String | MonoGut ZX Pro (PEEK) |
| Machine Used | True Tension Professional |
| String Bed Stiffness - RDC | 54 |
| String Bed Stiffness -FlexFour | 56.4 |
| String Bed Stiffness - SBS | 44 |
| String Bed Stiffness - ERT | 35 Kg/Cm |
| Racquet Flex, RDC | 58 |
| Racquet Flex, FlexFour | 44 |
| Racquet - In Plane Stiffness | 342.9 |
| Weight, Grams | 340 |
| Weight, Ounces | 11.99 |
| Balance, mm | 3234 |
| Balance, Inch | 12.72 |
| Length, Cm | 68.6 |
| Length, Inch | 27.03 |
| Head Width | 9.476 |
| Head Length | 13.052 |
| Head Area, cm2 | 626.7 |
| Head Area, Sq. Inch | 97.1 |
| Beam Height @ Grip, mm | 20.8 |
| Beam Height @ Mid, mm | 20.0 |
| Beam Height @ Tip | 20.0 |
| Beam Width @ Grip, mm | 10.7 |
| Beam Width @ Throat, mm | 10.8 |
| Beam Width @ Mid, mm | 11.5 |
| Beam Width @ Tip, mm | 12.2 |
| Number of Main Strings | 18 |
| Number of Cross Strings | 20 |
| Ratio | .655 |
| Main String Grid | 7.56 |
| Cross String Grid | 10.25 |
| Density (% of head filled with string) | 71.4% |
| Average Cross String Space | .513 |
| Average Main String Space | ,453 |
| Dynamic Tension, Kp, ERT | 35 |
| Dynamic Tension, Lbs/in | 195.76 |
| First Moment, Nm | .844 |
| Polar Moment | 335 |
| Torsional Stability | 16 |
| Swing Weight, Kg/cm2 | 319 |
| Swing Weight, Ounces | 11.25 |
| Swing Weight Calculated | 354.7 |
| Power, RDC | 44 |
| Control, RDC | 57 |
| Manueverability, RDC | 74 |
| Power, Calculated | 1811.3 |
| Head Points | 6.3 |
| Head Weight, % | 47.1% |
| Center of Percussion | 20.5 |
| Dwell Time, ms | 6.125 |
| Efective Stiffness - lbs | 28.0 |
| K, Lb/In | 173.08 |
| Recoil Weight | 152.3 |
| Twist Weight | 229.34 |
| End Weight | 139.8 |
| Tip Weight | 198.9 |
| 9 O'Clock | 100 |
| 3 O'Clock | 101.7 |
| Butt Cap | 137.4 |
| COF, Main | .383 |
| COF, Cross | .204 |
Racquet Quest, LLC
