Gamma X-2 appears to be off by more than 10 lbs

Discussion in 'Stringing Techniques / Stringing Machines' started by skandy, Jul 9, 2008.

  1. skandy

    skandy Rookie

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    I've recently purchased Gamma X-2 machine and strung two LM Radical OS rackets with it - my first stringing job ever. I've set the tension to 59 lbs and used Gamma Synthetic Gut (the usual tension and string type). Both rackets' stringbeds felt extremely tight. I went to hit with it and, indeed, it was way too tight, I almost got a tennis elbow after 30 minutes of hitting. Yesterday I've restrung one racket at 54 lbs and it still feels extremely tight! I've seen people on that forum saying that the machine was off by a couple of pounds, but mine seems to be off by 10 lbs at least! Is there a chance I'm doing something wrong? Any ideas what to do next?
     
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  2. fastdunn

    fastdunn Legend

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    No, drop weight is actually one of the most accurate machine if done right.


    Have you measured the tension with calibrator ?

    Have you ever forcefully level the weight ?

    Are you sure you set the tension correctly ? (One time, I set the tension with the wrong end of the weight !).
     
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  3. skandy

    skandy Rookie

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    > Have you measured the tension with calibrator ?

    You mean the tension on the racket? No, I don't have the calibrator, but it feels and plays damn stiff. When I pick up my rackets after restringing, I usually slightly hit the stringbed agains my head or knee (not the Youzhny-style, though :)), and this time it was painful :???:

    > Have you ever forcefully level the weight ?

    Never.

    > Are you sure you set the tension correctly ?

    Yes, I'm pretty sure I used the correct (inner) end of the weight. Besides, if I used the wrong end, then the actual tension will be lower than the incorrectly read tension.
     
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  4. Mansewerz

    Mansewerz Legend

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    Calibration means the machine is pulling accurate tension. You calibrate a dropweight to make sure that the sticker/engravings for the reference weights are correct.
     
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  5. skandy

    skandy Rookie

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    I understand that, but that is kind of my original question - can a machine be off by more than 10 lbs? It's hard to believe it, given that they all are assembled from the (presumably) same parts. I will definitely calibrate it when I get a chance.
     
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  6. Zhou

    Zhou Hall of Fame

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    You don't know that for sure. So just get a calibrator and check your machine.
     
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  7. 2handsbothsides

    2handsbothsides Semi-Pro

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    What are you comparing your machine to? The drop weight is a constant pull machine and will feel 5 or 6 pounds tighter than a job done on the popular lockout crank machines set at the same tension. Just find what tension setting works best for you on your machine. One of the best things about a drop weight is that it will produce repeatable results with no need to recalibrate. The spring in crank machine looses tension over time.
     
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  8. Gamma Tech

    Gamma Tech Professional

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    what type of machine did you use to have you rqt strung on?
    bret
     
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  9. skandy

    skandy Rookie

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    Gamma X-2, as the thread name says, that's all I know... just got it from Gamma couple of days ago... blue one... :) Are there different X-2s?

    Before I got it, I used to string them at either the local tennis shop or at Sports A u t h o r i t y - the tensions seemed to be slightly different, but that was OK with me. I'm not sure what kind of machines they use.
     
    Last edited: Jul 9, 2008
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  10. Bud

    Bud Bionic Poster

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    Not likely, since the tensions are stamped into the shaft.
     
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  11. Bud

    Bud Bionic Poster

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    Bingo... and even more than 5-6 if you let the string stretch... lift weight... stretch...lift weight... stretch... etc.
     
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  12. Bud

    Bud Bionic Poster

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    I think most places like that use lockout tensioners. This would explain the tighter feel of the stringbed.
     
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  13. WildVolley

    WildVolley Legend

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    Assuming the machine is put together correctly, it is probably not very far off. Calculating the tension that a lever with a weight will pull is Newtonian Physics 101. It should be simple enough to get a tension gauge to confirm this. Assuming the rod is marked correctly, this should be plenty accurate.

    I think that constant pull (or close enough) from a dropweight is giving you more tension than you are accustomed to with a crank (lock-out) machine. Ah, I see that's the opinion of most of the other comments.:)
     
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  14. Gamma Tech

    Gamma Tech Professional

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    if SA or the local shop used a spring tension (crank) machine then you need to lower your tension by 10% to start off with and adjust from there. so you probably want to be stringing your rqt on your X-2 in the mid-low 50s.
    bret
     
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  15. skandy

    skandy Rookie

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    Thanks for all the responses! In a couple of days I'll string it at 51 lbs and report back.
     
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