Steve Crandall's Squash Stringing Tips
Trends in Stringing: PEEK Vs. Nylon
By Steve Crandall
Vice President, Sales & Marketing
Ashaway Racket Strings
By Steve Crandall
Vice President, Sales & Marketing
Ashaway Racket Strings
Ever since we introduced our first polyurethane (PU) based nylon multifilament string at the end of last season - MultiNick® 18 - people have been asking me to explain the difference between it and our Zyex® (PEEK) based strings like our PowerNick® and UltraNick® strings. I've gone over some of this before, but as both nylon multifilament and PEEK multifilament strings comprise the largest proportion of strings in use today, the comparisons bear repeating. Besides, my mother always said she had to repeat things to me at least three times, and I think that's good advice.
The first thing that needs to be said is that how a string plays and feels for you is much more important than how it technically compares to another string, or even how it feels for another player. This is not just to say that everybody is different - which is rather a cliché - but that the same string will really play and feel differently for different players. If this were not true, there would be only one string!
PEEK stands for polyether ether ketone, the chemical name for the Zyex brand polymer filaments we use in our string. PEEK is a very robust high-temperature engineering grade polymer, noted for its toughness and durability. PEEK monofilaments and fibers have excellent abrasion resistance (over five times better than aramid fibers). They also have better dynamic stiffness ratios than any other synthetic string material, giving them the ability to stretch and snap back quickly, returning energy and power to the ball (we call it "soft power"). Finally, PEEK has exceptionally low creep, which is the ability of a string to retain tension when strung in a frame, extending the life of the string.
The first thing that needs to be said is that how a string plays and feels for you is much more important than how it technically compares to another string, or even how it feels for another player. This is not just to say that everybody is different - which is rather a cliché - but that the same string will really play and feel differently for different players. If this were not true, there would be only one string!
PEEK stands for polyether ether ketone, the chemical name for the Zyex brand polymer filaments we use in our string. PEEK is a very robust high-temperature engineering grade polymer, noted for its toughness and durability. PEEK monofilaments and fibers have excellent abrasion resistance (over five times better than aramid fibers). They also have better dynamic stiffness ratios than any other synthetic string material, giving them the ability to stretch and snap back quickly, returning energy and power to the ball (we call it "soft power"). Finally, PEEK has exceptionally low creep, which is the ability of a string to retain tension when strung in a frame, extending the life of the string.
How a string plays and feels for you is much more important than how it technically compares to another string, or even how it feels for another player. US #1 ranked Amanda Sobhy tested the new PU-based multifilament MultiNick 18 against her long-time multifilament Zyex favorite, UltraNick 18. She chose to stay with UltraNick 18, preferring the consistent feel and soft power generated from the Zyex-based string.
As for nylon, I'd wager that nearly everyone who has ever played squash has used nylon strings at some point. Nylon has been the dominant material for squash string for many years and remains very popular. Nylon strings are relatively inexpensive, they are quite responsive, and players love their "feel" and "playability."
Nylon strings don't spring back quite as quickly as Zyex but depending on the design and gauge of the string, can be either quite stretchy or quite stiff. Nylon's main drawback is that it loses tension and wears more quickly than other string materials, leading to a shorter life in the racquet. It is also not as durable for power players.
Enter PU, or polyurethane, which is one of - if not the - most versatile polymers known. Generally known for its toughness and abrasion resistance, when used in racquet string it permeates the nylon sheath, chemically bonding the whole into a single, unitized matrix. Unlike UltraNick 18, which has a woven nylon wear layer over a PEEK multifilament core, MultiNick 18 has no separate wear layer, just the smooth PU surface. Because of the material's natural adhesive properties, this surface helps grip the ball.
In adding PU to nylon, our intention was to add durability to the nylon for heavy hitters, and improve abrasion resistance, which would reduce notching and improve the life of the string. MultiNick 18 does these things very well. The added strength improves durability, especially on off-center hits near the edge of the frame.
But what really surprised us was that the PU also improved the tension holding ability of the string while retaining nylon's soft feel and comfortable playability. I talked to a number of our sponsored pros at last October's US Open to get their reactions.
US #1 ranked Women's player (and #13 PSA) Amanda Sobhy signed with Ashaway last summer. She tested the new PU-based multifilament, MultiNick 18, against her long-time multifilament Zyex favorite, UltraNick 18. She chose to stay with UltraNick 18, preferring the consistent feel and soft power generated from the Zyex-based string.
Ashaway's newest sponsored player is Leo Au from Hong Kong, currently ranked #22 on the PSA World Tour. Leo tried several of Ashaway's Zyex and nylon strings, selecting the new MultiNick 18. He felt this string played closest to his previous nylon string, which was a 17 gauge string. He liked the way the MultiNick 18 cut and grabbed the ball, as well as the superior durability, which allowed him to use an 18 gauge string for the first time ever.
Two well-known English professionals made completely different choices. Daryl Selby, who has always used UltraNick 18 in his frame, playtested MultiNick 18 but preferred the feel, consistent performance, and tension stability of his UltraNick 18. Adrian Waller, on the other hand, who previously used both Zyex-based UltraNick 17 and SuperNick® ZX, switched to MultiNick 18 last summer and loves it. He really likes the way it cuts and grips the ball, and has found the durability of the multifilament PU string to be excellent.
So, of four leading professionals, two switched to PU multifilament nylon strings and two chose to stick with their Zyex-based multifilament strings. What does this tell you? First, that no one string is technically better than another. Each has its own playing characteristics that may - or may not - benefit your style of play. Second, as we noted above, the key issue is how a string plays for you. The options are available, the choice is up to you.
ZYEX® is a registered trademark of Victrex Ltd.
This article previously appeared in Squash Magazine
Steve Crandall is Vice President of Marketing and Sales at Ashaway Racket Strings. Part of the sixth generation to run the family-owned business, he is a lifelong racket sports fan and well-known writer and commentator on all things string. Follow him on Instagram at ashawayusastring
Nylon strings don't spring back quite as quickly as Zyex but depending on the design and gauge of the string, can be either quite stretchy or quite stiff. Nylon's main drawback is that it loses tension and wears more quickly than other string materials, leading to a shorter life in the racquet. It is also not as durable for power players.
Enter PU, or polyurethane, which is one of - if not the - most versatile polymers known. Generally known for its toughness and abrasion resistance, when used in racquet string it permeates the nylon sheath, chemically bonding the whole into a single, unitized matrix. Unlike UltraNick 18, which has a woven nylon wear layer over a PEEK multifilament core, MultiNick 18 has no separate wear layer, just the smooth PU surface. Because of the material's natural adhesive properties, this surface helps grip the ball.
In adding PU to nylon, our intention was to add durability to the nylon for heavy hitters, and improve abrasion resistance, which would reduce notching and improve the life of the string. MultiNick 18 does these things very well. The added strength improves durability, especially on off-center hits near the edge of the frame.
But what really surprised us was that the PU also improved the tension holding ability of the string while retaining nylon's soft feel and comfortable playability. I talked to a number of our sponsored pros at last October's US Open to get their reactions.
US #1 ranked Women's player (and #13 PSA) Amanda Sobhy signed with Ashaway last summer. She tested the new PU-based multifilament, MultiNick 18, against her long-time multifilament Zyex favorite, UltraNick 18. She chose to stay with UltraNick 18, preferring the consistent feel and soft power generated from the Zyex-based string.
Ashaway's newest sponsored player is Leo Au from Hong Kong, currently ranked #22 on the PSA World Tour. Leo tried several of Ashaway's Zyex and nylon strings, selecting the new MultiNick 18. He felt this string played closest to his previous nylon string, which was a 17 gauge string. He liked the way the MultiNick 18 cut and grabbed the ball, as well as the superior durability, which allowed him to use an 18 gauge string for the first time ever.
Two well-known English professionals made completely different choices. Daryl Selby, who has always used UltraNick 18 in his frame, playtested MultiNick 18 but preferred the feel, consistent performance, and tension stability of his UltraNick 18. Adrian Waller, on the other hand, who previously used both Zyex-based UltraNick 17 and SuperNick® ZX, switched to MultiNick 18 last summer and loves it. He really likes the way it cuts and grips the ball, and has found the durability of the multifilament PU string to be excellent.
So, of four leading professionals, two switched to PU multifilament nylon strings and two chose to stick with their Zyex-based multifilament strings. What does this tell you? First, that no one string is technically better than another. Each has its own playing characteristics that may - or may not - benefit your style of play. Second, as we noted above, the key issue is how a string plays for you. The options are available, the choice is up to you.
ZYEX® is a registered trademark of Victrex Ltd.
This article previously appeared in Squash Magazine
Steve Crandall is Vice President of Marketing and Sales at Ashaway Racket Strings. Part of the sixth generation to run the family-owned business, he is a lifelong racket sports fan and well-known writer and commentator on all things string. Follow him on Instagram at ashawayusastring
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