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Posted on May 6, 2019, in Good News!. Bookmark the permalink. 36 Comments.

  1. Dear John,

    I noticed in your ‘By the Numbers Post’ that you say for twistweight , “the higher the better” … however, if one is to increase swingweight to a value of above 340 grams, would a higher twistweight value of 14+ be detrimental to both manoeuvrability and spin potential?

    • Lance, thank you for the very good question! Twist weight can be a function of added weight or simply a wider racquet head. The farther from the neutral axis of the racquet the weight is the more affect it has. For example a Prince Phantom Pro 100 has a wider head than, say a Wilson Blade so the natural twist weight is 252.3 with a swing weight of 324 compared to the Blade that has a swing weight of 337.0 and a twist weight of 233.8.

      As swing weight increases the maneuverability may decrease a little but the “momentum” should increase the spin potential if the player is strong enough to move around the swing weight.

  2. Steven Klurfeld

    Hi John, I’ve enjoyed my Yonex DR98,(16×19) pattern strung at 51 lbs. I recently started using the HDpro 97.(18×20). and 50 lbs feels much tighter. By how many pounds should I drop tension on this tighter string pattern to have the strung bed feel more similar to what I had?

    • RacquetQuest

      Steven, if everything else remains the same a 18% reduction in tension setting would be where I would start.

      Because of the more open pattern the 16×19 string bed will include some slippage that may not occur on the 18×20 so they may never feel exactly the same.

      Let me know how it feels!


  3. hi john, what do you think about the pre-stretch on the TTSM. do you still use the pre-stretch? is it always 15lbs mains and 20 lbs crosses? can i enable the pre-stratch by leveling down?
    thanks in advance


    • RacquetQuest

      Simon, sorry for the delay! I do use pre-stretch on this machine dependind on the string and racquet. I use 15 and 17 for most racquets. This pre-stretch function is very precise and I find it helpful.

      I am not sure what you mean by”leveling down”.

      Keep it up!


  4. Hi John! Love your webpage and the informative content! since a few days i am a proud owner of a true tension stringing machine! bought it from a lady, she worked for Fischer Austria as a full-time stringer in the 90’s and strung about 25.000 racquets with that beauty. your video about the stringing was very helpful for me, but i still have some questions and in a search for the manual. i can’t find anything on the internet. you might have some info material to share?
    Thanks in advance

    Simon from Austria

    • RacquetQuest

      Simon, thank you for the message! These machines are simply the best! We have, currently, five of them and I just acquired one of the very first machines ever made! It is absolutely brand new. I still marvel at the functionality of the machine. I will look around for a manual but I am not sure I have seen one for several years. I will let you know! John

      • Thank you for your quick reply, stringing with the machine is so much fun. Feels like craftmanship. I will listen to your podcast this days, so i can learn some more…
        Keep up the good work!

  5. Louis DeLaPena

    Hello John!
    My question is: I start my mains by clamping and backing up with starting clamp on inside then proceed to string 3 mains opposite of that, then start side with starting clamp and fixed clamp. When I get to second hole and try to clamp, I can’t get close enough to so there is space between racquet and where I clamp. Should I continue doing it this way? Or try different starting method? When tension next one, will that self correct?
    Thanks for any advice!!


  6. Hi John, Thanks for all you write about, and your expertise. I recently moved to the 97 Vcore Pro HD, and love the weighting balance and stiffness. I’m looking to retain some of the ball pocketing from more open patterns, is there a string and tension you might recommend I use, without losing control?

    • Steven, sorry for the delay! This is a very dense string pattern so the string will need to a be high eleongation model to acheive the “pocketing”you want. Depemding on how many hours you want the string to last I have had good feedback with Yonex Rexis both 125 and 130 gauge.

      Our demo is strung with a pre-production PEEK fibre 1.25mm from Victrex at 55 pounds with a DT of 37 and the reponse has been very favorable.

      Let us know what you try.

  7. Hi John!
    Question about tying Poly on gut. I know this is a no-no. I was thinking, if i I had a situation such as this, could I use a small piece of electrical tape and wrap around the gut where I would tie knot. Do u think this would suffice in protecting the Gut when tying knot?
    Thanks for any advice!!


    • Louis, thank you for the question! I would not rely on tape to protect the natural gut against the polyester knot. The best option is to tie off on a cross string of the same material. You can prepare the tie off hole before stringing. If this is not possible a short piece of protective tubing can use on the gut at the tie off location if the hole is large enough. Then tie the polyester off on the tubing, not the gut material. I would sure try to find a good cross string to tie off on, though!

      • Thanks for the advice! Probably should have some tubing in my tool arsenal for this reason and other situations. I guess I would rather use the tubing solution rather than comprising a hole not made for tie off. At least on a customer racquet, though if done with care shouldn’t be an issue.
        Thanks again!!

        • Good idea, Louis! Did you know that many racquets have grommets large enough to accommodate two (2) stings easily? Take a look at the racquets you have and you may see an extra large grommet on the sides near the top and bottom.

          • Thanks John! I have noticed some are larger. Since I don’t string with gut very often, I’ve never had to improvise and preparing for situations before they actually occur, especially with advice from experts!!

  8. Hello! I use an offset tool on outside of racquet to protect string when starting crosses. I see many stringers use starting clamp on outside with no protection when starting mains. I would think you need to protect string from starting clamp when starting mains this way. Thoughts? Thanks!


    • Hi, Louis, and thank you for the message! You are doing the right thing by not clamping too close to the grommet where the string must bend.

      Some stringers have never done this and many have not had a problem they were aware of so it continues to be their procedure.

  9. 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.

  10. 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…

  11. 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.

  12. 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

  13. 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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