Is ERT-300 or Mini-STT useful or a must for stringer?

Discussion in 'Stringing Techniques / Stringing Machines' started by Dr. Perry, Apr 23, 2013.

  1. Dr. Perry

    Dr. Perry New User

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    My daughter practices tennis daily (5-6 days a week) and I am concerned if she knows when to ask to have the racquet restrung (she is turning 11). Do you think a tool like ERT-300 or mini stt can address the concern? Or I should simply restring the racquet once every 12-15 hours?
     
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  2. mikeler

    mikeler G.O.A.T.

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    If you have an iPhone then download RacquetTune.
     
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  3. esgee48

    esgee48 Hall of Fame

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    Depends. (Wishy Washy Answer, I know!) The 2 devices you mentioned measure string bed stiffness. Your daughter or you would have to know what is her range of optimal SBS for you to decide that it is time to restring. Mikeler's answer assume you know what range of tensions are optimal before you need to restring. It is a $1.99 option which works very well. Also from the same guy, you can get a range of tools. I prefer the Gamma String tension Tester just so I can determine when the reference tension drops too far. It isn't anywhere as accurate as RT, but you can still determine tension drops and you don't have to buy an iPhone.
     
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  4. Dr. Perry

    Dr. Perry New User

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    I heard of racquetTune a lot. You need to generate the vibrate yourself, don't you? Would it affect the result as your tap would be different from time to time? It seems it functions like mini stt.
     
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  5. Irvin

    Irvin G.O.A.T.

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    You're correct and you also have to position the racket so the vibrations are picked up properly with RacquetTune. Sten suggests using a hard object like a screwdriver or spoon and always tap the racket in the same location. Also you have to be in a location with very low background noise. It is best if you build a custom string for each string you use. All in all it is a good app if used properly but like any other tool if you don't use it right - garbage in garbage out.
     
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  6. mikeler

    mikeler G.O.A.T.

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    Most times, the readings are either the same or off by 0.1 or 0.2 pounds. Well within the type of accuracy you need to measure tension loss. Calculating custom string factors is a pain, so I only use it to measure tension loss and not absolute tension. It does a good job of this IMHO.
     
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  7. hyperion99

    hyperion99 Semi-Pro

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    I personally like the ERT-300 for its consistency.
    It make its own vibrations to determine the tension of the racket(you need to use the wheel that comes with the ERT-300 to translate dynamic tension to actual tension).
    http://www.tennis-warehouse.com/descpage-ERT300.html


    Check out this video.
    This talks about the ERT-300 and the racket tune app(I have never used racket tune).

    http://www.youtube.com/watch?v=FcXvDWI3EwU

    Dynamic Tension:
    Stringbed stiffness (measured in DT - Dynamic Tension) is the major parameter that determines the playing characteristics of a tennis racquet. This value represents the force which is necessary to push down the stringbed for 1 cm in a contact area about the size of a tennis ball. The DT value is dependent on a number of parameters: string pattern, string, tension, stringer, time point of measurement and so on.

    Hope this information helps.
     
    Last edited: Apr 23, 2013
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  8. Dr. Perry

    Dr. Perry New User

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    Is the device well built? The claws are made of platstic, did it concern you?

     
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  9. hyperion99

    hyperion99 Semi-Pro

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    For me the device has always worked.
    I think it's well built.
    The claws have always stayed on the racket so I don't think it is much of concern.
     
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  10. Dr. Perry

    Dr. Perry New User

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    When I look at the number of views and replies, I can say neither item is a MUST. Maybe there is a more practical way to gauge a racquet's restring timing. My guess is ERT-300 is too pricy and Mini-STT's market awareness is low.
     
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  11. Irvin

    Irvin G.O.A.T.

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    I have an old stringmeter I got probably 30 years ago. For some reason I called Stringmeter about something and they thought my Stringmeter was broke and offered to send me a replacement. I don't think there is a cheaper or easier to use tool out there that carries with it a guarantee like the Stringmeter. Yes RacquetTune is low cost but requires an iPhone or iPad and they aren't cheap.
     
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  12. hyperion99

    hyperion99 Semi-Pro

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    I wonder if racket tune is gonna be available for the android any time soon.
     
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  13. Irvin

    Irvin G.O.A.T.

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    Sten (the developer Stone Age) says there is not enough interest to justify it. I will try to find the quote.

    EDIT: This quote is from three years ago but I don't think he has changed his tune any.

     
    Last edited: Apr 24, 2013
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  14. Dr. Perry

    Dr. Perry New User

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    I looked into stringmeter too. Compared to ERT-300, Mini STT, racquet Tune ..., is this simple device good enough to tell about the stringbed?

    By the way, I don't recall seeing any of these is found in the pro's bag check.

     
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  15. hyperion99

    hyperion99 Semi-Pro

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    Tour players restring their rackets every day so they don't really have a need to have these tools in their bag.
     
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  16. hyperion99

    hyperion99 Semi-Pro

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    Thanks Irvin.

    Android has advanced a lot in the last few years though.
    Maybe he can consider it since there's more of a market now than 3 years ago.
     
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  17. kadishack

    kadishack New User

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    Actually I have seen Wozniacki use it quite frequently on the court.
    [​IMG]
     
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  18. Irvin

    Irvin G.O.A.T.

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    Yes you beat me to it. But don't believe everything you hear and only half of what you see. Who knows if she is using it to see if it is time to switch or because she is paid to use it? Maybe she likes to use it to test the string bed when it does really feel good (or bad) to see what tension to use for restringing.
     
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  19. Rabbit

    Rabbit G.O.A.T.

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    I don't believe the ERT gives a tension you can set on a machine, it gives Dynamic Tension which is vastly different.
     
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  20. hyperion99

    hyperion99 Semi-Pro

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    If the pros are switching their rackets every few games I don't see the reason for them to have the ERT at this point.

    I think it could be more of a sponsorship deal than anything else (I could be wrong though).
     
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  21. Irvin

    Irvin G.O.A.T.

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    Not all pros switch their rackets every few games.
     
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  22. RJYU

    RJYU Rookie

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    She uses it to find out when she wants to change to a new racquet. She doesn't have a set game schedule when for she changes frames, so she's checking the DT reading. When it drops to a certain DT reading, she grabs a new stick.
     
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  23. Dr. Perry

    Dr. Perry New User

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    This is the only incident I can find a pro uses the ERT-300. Maybe its usefulness is limited?


     
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  24. hyperion99

    hyperion99 Semi-Pro

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    If your not re-stringing rackets every day then it's useful to have for knowing when the tension is low enough to re-string the racket.
     
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  25. hyperion99

    hyperion99 Semi-Pro

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    Most pros switch there rackets after a few games (no set number of games because it's personal preference) unless they feel they are having a good streak and feel with the racket they are currently playing with.
     
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  26. Rabbit

    Rabbit G.O.A.T.

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    Well, this isn't necessarily true. There was an article by a guy from Luxilon who said that the vast majority of pros do not change their racquets after a few games. He said there was a minority at the top of the game who did this, but most pros did not.

    RJYU, if you're still reading, do you have any thoughts? I also thought I saw where John Isner doesn't restring all too often or change frames on a time clock.
     
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  27. corners

    corners Legend

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    In my opinion RacquetTune is far superior to an ERT. RacquetTune has been validated and is extremely accurate. It does not tell stringbed stiffness, but can tell you tension loss very accurately.

    An ERT measures static stringbed stiffness. This is essentially useless because each string type has a different relationship between static stiffness (how stiff it is when pushed on slowly) and dynamic stiffness (how stiff it is during a fast impact, like when hitting a ball.) For example, gut and copoly stringjobs will test quite similar on an ERT, but we know from lab tests that in dynamic play gut is half as stiff as copoly. So an ERT can tell us nothing about how stiff a stringbed is during play.

    I suppose an ERT can still be used to show a change of static stringbed stiffness over time, which could then be used as an indirect method of estimating tension loss. But with racquettune you can measure tension loss directly, not indirectly. ERTs are obsolete technological relics.
     
    Last edited: Apr 24, 2013
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  28. jazar

    jazar Professional

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    Plenty of pro players use ERTs, but they just don't do it on court. Some like to check on the ERT straight away when they pick the racket up from the stringer.
     
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  29. RJYU

    RJYU Rookie

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    Most pros certainly do not switch frames after a few games, and most pros don't even switch frames every ball change. I don't know the exact numbers, but I do know the majority of players don't have a set schedule for switching frames.
     
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  30. Rabbit

    Rabbit G.O.A.T.

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    Thanks! (ten characters)
     
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  31. Dr. Perry

    Dr. Perry New User

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    Have you seen people carry mini-STT too? It makes sense to have a ruler-like device around after the stringing job is done. Just don't see it often on court.

     
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  32. hyperion99

    hyperion99 Semi-Pro

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    Thanks for the feeback Rabbit.
     
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