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Posted on May 6, 2019, in Good News!. Bookmark the permalink. 15 Comments.

  1. John — In hybrid stringing, players are hoping to get the benefits of the differing characteristics of two strings. But what are we trying to accomplish, and what are we actually accomplishing, in terms of string bed stiffness? For instance, when I string a natural gut in the mains and a poly in the crosses, should I be stinging the gut relatively high and the poly relatively low, as I would in full beds of either? Say I string the mains at 57 lbs. and the crosses at 42. Even though the strings have very different inherent stiffness ratings, does that disparity in tension have unintended consequences on the string bed stiffness, and therefore on performance?

    • RacquetQuest

      Hi, Jacob and thanks for the message.

      Individual strings with different stiffness characteristics will produce a string bed stiffness and that is what the ball, and body, feel. The shorter the strings the tighter they will feel but there are normally more cross strings than main strings so the ratio is important.

      In terms of actual accomplishment it would be better measured by tension stability due to the more elestic string offering a restoring force to the stiff or lower power string.

      In some cases the SBS of a hybrid will be greater than a full polyester. I would not recommend the wide ratio you reference 57/42 and in fact would start with the same tensions. Polyestr can feel quite soft

      That is a long way around your question so I hope it helps.

      • That is helpful. But I wonder under what circumstances a polyester can feel quite soft?

        • Jacob, you may get two replys on this question. The most common circumstance is that the racquet has distorted and recoved rendering the string bed stiffness lower than expected. The stiff string does not have much elongation so not much “tension” so the racquet after stringing will change shape a little to try to remove built up stresses. This change can decrease SBS a lot therefore the soft feel of stiff string. However, When the ball is hit really hard to generate depth and maybe some spin the stiffess of the string bed inceases substantially, then retracts after impact. It is that increase in stiffness that may cause discomfort.

  2. stringweaver

    Hi John,
    In your stringing video “Standard String Process” you indicated that you have used string spreaders for many years to reduce friction when weaving the crosses. The tools you use do not appear to be available any longer, though there are two other string spreaders currently on the market–the StringWeaver (from and the MK2 (from Despite their obvious benefits, string spreaders have not been widely adopted by racquet stringers. Why do you suppose that is? I look forward to your opinion.

    • RacquetQuest

      Dennis, as far as I can tell most stringers don’t want to take the time to add a “step” to their technique and their customers are perfectly happy with the result.

      • RacquetQuest

        Dennis, I have some additional thoughts on your question and in fact I have written about them on several occasions;

        Until the customer has experienced the difference a properly strung racquet can make there is no incentive for a stringer to try to do better becasue it is not going to be expected by the customer.

        A few years ago a stringer was concerned they were loosing business to big box stores. This was business they once had. I asked what they did differently than the big box and they could not come up with anything definitive! They should have been doing a better job educating the customer.

        So, if the customer doesn’t know a better playing racquet is possible there is no incentive to change the way it is being strung.

        • Dennis Sadowski

          John, thank you for your additional thoughts on the subject of using string spreaders. My feeling is that by using a spreader they not only get a better result but they make the job easier and more pleasant for the stringer. After all, stringing a couple of 18×20 frames with sharped edged poly is quite literally a pain in the finger tips. The gap created by the spreader certainly makes weaving and pulling the crosses easier. String spreaders only take a few seconds to mount and remove, so they don’t add time to the job, and in fact may reduce the overall time. If stringers don’t use a spreader to benefit their customers, they should at least consider the benefits to themselves.

          • RacquetQuest

            Dennis, thaks for the response! We have tried for years to teach “best practices” but it has not worked as far as I can tell. Most stringers have not been exposed to these practices and have no idea the advantages, and I said before, until the customer demands better it is not, in my opinion, going to happen.

            It is too bad…

  3. What are your favorite strings and why?

    • RacquetQuest

      Sig, here are some of the strings my clients and I like:

      Babolat VS Touch and VS Team – Natural gut that offers the benefit of power and comfort.
      Ashaway MonoGut ZX and ZX Pro – PEEK material that offers very good durability and arm/body protection.
      Yonex Rexis – Nylon multifilament is a will made multifilament that offers great playability with better than average dudability for a multifilament
      Tecnifibre HDX Tour – Nylon multifilament bundled with polyurethane for great control potential but lacking some in durabilty.
      Head Reflex MLT – A technical multifilament with slighty higher durability than most.

      We don’t promote polyester based string for most players but we have found that Head Lynx offers a good balance between stiffness and comfort. Volkl V-Star also offers some comfort in the form of polyester string.

  4. Hi John, I’ve seen, you has for the Babolat RDC Calibration 3 Rods. Could you tell me please the Diameters, Length, material and weight of the tree Rods?
    Thanks in advance

    • RacquetQuest

      Thank you for the question! I will send you the specifications tomorrow. I have “calibration” rods from various testing devices and have made a set for the RDC since calibration rods were difficult to get directly from Babolat. Thanks again!

      • RacquetQuest

        The one RDC Calibration Rod I have has the following specs:
        Diameter = 28mm
        Length = 36.5 cm
        Weight = 1756.6 gr
        Swing Weight = 315 kg/cm2
        Material = Not Sure

        I made several bars but use a 325:
        Diameter = 25.37mm
        Length = 38.5cm
        Weight = 1524.5 gr
        Swing Weight = 325 kg/cm2
        Material = CR Steel

  5. RacquetQuest

    I am looking forward to this new “Ask John” section! I believe this wil give all the viewers of this site an easy and quick way to ask any question!

    Please use it!


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