I am not talking about the “peeking” type of peek but instead the material PEEK. For all of you chemists it is Polyether ether ketone and it is being used as a material for tennis racquet string, which, of course, is what we care about!
I have been working with Ashaway Line & Twine Company for several months to understand how this material can be a viable alternative to very stiff string, and, even a cost effective string for those needing a more “forgiving” gut like impact. In fact the Ashaway MonoGut ZX Pro has a dynamic stiffness similar to natural gut! As most players know natural gut is the very best string for those wanting arm protection but it is sort of expensive.
At first glance PEEK string looks exactly like many polyester based string. But that is where the similarities end. PEEK has elongations of 10% to 12 % at sixty (60) pounds whereas polyesters will be about 4% to 6% elongation. Power Potential is directly related to elongation so the PEEK material should return more energy to the ball.
Player response to PEEK string has been very positive and I see it as a material that will increase durability, stability, and playability in tennis racquet strings. MonoGut ZX can be used as a 100% system, and, in fact, I would recommend using a PEEK material as 100% the first time. I have clients using MonoGut ZX Pro in a hybrid format with natural gut and this may be the ultimate setup!
As with any engineering material some care is required to assure the string is installed in the racquet properly. Through our long association with PEEK material we have developed the techniques that are required to assure a winning result.
So, if you are looking for playability, durability, and stability (tension maintenance) you should consider taking a PEEK!
To stretch or not to stretch is a question some technicians have pondered. What is stretching? I am talking about stretching a set of racquet string. A set is typically 40 feet long so you need that amount of room to stretch the entire set in one straight pull. What does this mean to you the consumer? Please read on.
Pre-stretching the typical tennis string will increase the stability. That is reduce the affects of creep exhibited by nearly all tennis strings. Stretching will enhance the elongation of the string by removing many of the bonding fractures that occur when the string is tensioned by the machine or ball contact. A stretched string will maintain tension longer and will produce a slightly higher string bed stiffness.
Stretching the string by hand is the preferred method and it takes about 25-30 seconds to render a string stretched. The string should exhibit little or no “recoil” after this stretching procedure. This can make the string easier to handle for the technician.
There is no danger of damaging the string by proper stretching technique. In fact the maximum load a human stretcher can reach and hold is about 40 pounds which is well below the yield strength of the string.
So, you the consumer should request that your string be pre-stretched. And, you the technician should certainly look into the advantage of pre-stretching. Why don’t you experiment with stretching and decide for yourself?