Need some insight....

Discussion in 'Stringing Techniques / Stringing Machines' started by ps2dcgba, Nov 1, 2010.

  1. ps2dcgba

    ps2dcgba Rookie

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    I normally send my rackets to a stringer who use's a crank machine, I usually string around 45-48lbs, however a shop brought in a new electronic machine, I was extremely excited to see this and wanted to test the machine out, gave the shop my racket and saw the stringer perform his magic, I noticed on the LCD display it allows you to select 'Natural Gut' ,'Synthetic gut','Polyster',etc strings, it also allows pre stretching by a certain percentage.

    Just as the stringer was preparing my racket, you know they align the strings before 'mounting', I noticed that the stringer when he pulled on the first main, he pulled only 42lbs, I asked him why...and the reply I got was that tensioning by the machine does not equate the tension desired so they compensate...while he was pulling at 42lbs when my requested tension was supposed to be 48lbs, I figured the machine was brand new, may be it needs some calibration to some extent....waht do I know....anyway I got home, I normally let the racket 'rest' for 24-48 hours.....I am use to it lol. I got on the courts and tried the racket out.....the string tension felt definitely more than 48lbs, it kinda felt more to 54-56lbs.....

    My question in general is, those with experience with electronic stringers, if you wanna pull 48lbs, do you input 48lbs or some other tension........

    Thanks in advance.
     
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  2. mad dog1

    mad dog1 Hall of Fame

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    it's the difference btwn constant pull vs crank. constant pull is exactly that...the tension head pulls to 42 lbs and when the string stretches and slowly loses tension after the initial pull, the tension head will repull tension back to 42 so the end result is a stringbed that is pretty close to the reference tension.

    a crank will pull to 45 lbs and "lock out". depending on how long it takes your stringer to clamp the string from the time the machine locks out, the string can stretch and lose up to 15% of the reference tension so by the time he clamps, the tension could be as low as 38-40 lbs. that's basically why your racquet feels so much tighter coming off the electronic machine.
     
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  3. Aggro

    Aggro Rookie

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    I compensate for it sometimes - some people i know used to have their strings done on a manual machine and i've just upgraded to a electronic machine.

    First job i did was for myself - a multi at 61lbs with pre stretch on and my god it felt about 80lbs!!

    I always drop a few lbs less for some people to compensate for the higher overall tension from the machine.
     
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  4. Irvin

    Irvin G.O.A.T.

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    Good explanation 'mad dog1' but not quite. On a lock out machine the tension pulls to the set tension and locks out. Then it starts losing tension. It has nothing to do with how long it takes to clamp the strings. After the string is clamped it will continue to lose tension but not as much as it did originally.

    Most of your tension is lost just after reaching the reference tension. That is why the constant pull is more desirable it continues to pull to the reference tension until the string is clamped.

    When I strung with my lock out I would release the tension and pull again in about 5 seconds for those customers that wanted a double pull.

    Irvin
     
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  5. dgdawg

    dgdawg Professional

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    Originally Posted by mad dog1
    ...a crank will pull to 45 lbs and "lock out". depending on how long it takes your stringer to clamp the string from the time the machine locks out...



    @ Irvin....I hear you, but mad dog was right on (with your comments being "right on" as well)
    Let say it takes an experienced stringer 3-4 sec to clamp. Thats 3-4 sec the string is stretching over....16"-18". Clamp the string and you decrease the length by....6"-8".
    A "lock out" tensioner stops pulling. A CP tensioner continues pulling until the string is clamped. (3-4 sec)
    Not taking into consideration clamp-base drawback and other factors, a CP tensioner will easily produce a SBS 10%-15% higher.
    Anyway, this discussion is like beating a dead dog.
     
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  6. bugeyed

    bugeyed Semi-Pro

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    I agree with this for a lockout machine, but it would be true for CP. Stringing on a constant pull machine challenges a stringer to be more mechanically consistent & methodical to get a repeatable result. That's one reason that we were given the same players racquets to string for a whole tournament. IMO on a lockout shortening the length of the string by clamping makes little or no difference to the string tension loss. Each MM of a string elongates at it's own rate regardless of the overall length of the piece involved. I realize that this is an issue ripe for debate, so I am not trying to be difficult, just want to understand the physics of it. I am in the process of choosing a machine & would like a CP machine, but the budget wants a manual machine, so the choice is between a lockout or drop weight. I have used a Babolat Star, Prince & Ektelon H, but never a drop weight. Any advice is appreciated.

    Cheers,
    kev
     
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  7. Irvin

    Irvin G.O.A.T.

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    ^^ I agree it is like beating a dead horse but if it helps someone understand I am all for it. To heck with that dead horse.

    A constant pull tensioner will continue to pull tension even after the string is clamped. A lockout tension will also continue to pull tension even after the string is clamped. This is very simple to prove. After you pull tension on your string and clamp it remove the tension and what happens? Drawback no matter what type of tensioner you use. Therefore, all tensioners pull tension until they are removed unless you leave them on until the string rots.

    A true constant pull (I say true because some constant pulls are not) will continue to pull at the set tension until it is removed. If your set tension is 60 lbs the tension on the string connected to the tensioner is 60 lbs until it is removed. It is like hanging a 60 lb weight on the string and the string tension will remain at 60 lbs even though it will continue to stretch.

    With a lockout tensioner once the set tension is reached (and if the lockout is adjusted properly) the tension head is held at that same position until it is removed. The string will start to stretch but since the length does not change it will not really stretch any more becuase the tensioner is locked in position. Since the string does not stretch the tension will drop. The tension drop on the string is greatest at first and becomes less as time for on. If you double pull on a lockout tensioner you can recover some of the initial tension loss. But on a lockout there is always going to be some tension loss between the time the tension head locks out and the time the string is clamped. That's the nature of the beast.

    I have heard all kinds of numbers that a constant pull tensions the string anywhere from 5% to 20% higher than a lockout but I know enought not to believe everything I read. But let's assume there is some difference because there is and I am not arguing against that. You could use a stringmeter to measure the difference if you wanted to with the free string scale on the stringmeter. If the lockout is 5 lbs off raise the tension 5 lbs. If it is 5% off raise the tension 5%. Whatever it is off raise the tension by that amount and there you go. If I tension a stirng with at lockout at 80 lbs and with a constant pull at 40 lbs do you think the constant pull is 10% - 15% higher? LOL

    Everyone tells me that a constant pull is better than a lockout for one reason or another, but like I said I don't believe everything I hear. String bed stiffness or dynamic tension is measurable and that measurement can be duplicated on either a constant pull or lockout tensioner.

    Given a racket I do not think there is anyone in the whole wide world who could tell if it was strung on a constant pull or lockout. Best they could do is guess right 50% of the time.

    Irvin
     
    Last edited: Nov 2, 2010
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  8. Irvin

    Irvin G.O.A.T.

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    ^^ But I would like to add that if I was manufacturing a constant pull tensioner I would like everyone to think constant pull was better and that mine was the best of all. Looks to me like the marketeers have a lot of people fooled. I am either too simple minded or not good enough to be able discern the difference.

    Irvin
     
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  9. vkamphonephong

    vkamphonephong New User

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    I think with this statement, you are missing the point of the 10% and 15%. Ask yourself if you strung with a constant pull and a lockout both at 60lbs, would the end result be a tension of 10% - 15% more for the constant pull. The answer would depend on the time it takes the stringer to clamp the string on the lockout machine.

    Doing a comparison the way you did really makes no sense, but I understand you were trying to get a point across.

    So to answer the OP's question, I think if the electric stringing machine were calibrated correctly, it would be closer to the actual tension. I don't know if the stringer asked you if you usually strung your racquets on a constant pull or lockout, but if he did and you responded lockout, he probably adjusted the tension to what you are used to with a lockout.
     
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  10. mad dog1

    mad dog1 Hall of Fame

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    hi irvin,

    as a test, i strung a couple of rossi f200s. one on my gamma 6004 (crank) and the other on a stringway ms200dx (constant pull). the purpose was to try and achieve the same end result. the stick strung on the stringway was set to 46 lbs. trying to factor in a 10% loss in tension on a lockout, the stick strung on the gamma was set to 51 lbs. a few days later, i brought the 2 sticks over to my friend & he checked the stringbed tension on both w/ his iphone. the stringway strung stick came out at ~47 lbs while the gamma strung stick measured out at ~42-43 lbs. i think the readings on the iphone were high due to the fact i wasn't sure of the exact headsize of the f200. i thought it was 80 sq in when it was probably closer to 82 or 83 sq in. anyways i strung on the stringway first and did the 2nd stick on the gamma immediately after. the string used for both was gosen og micro 17g. from an accuracy point of view, the CP machine was far more accurate. w/ a CP machine, it's easy to know what tension you're going to get while with a crank, you have to "guess". how much stretch you're going to get will depend on what type of string you use. polys and kevlar stretch less than syn guts, multis and guts. and although i haven't tested this theory, but i would venture to guess that there's probably no guarantee every syn gut stretches the same amount.

    so is constant pull better? based on my own experiment, i think it's definitely easier to get consistent results that are much closer to the reference tension.

    footnote: also i did check the calibration on both machines using my ultrasport50 scale prior to stringing to insure that my test would produce accurate results.

    to the OP: if my post has gone off topic, my apologies.
     
    Last edited: Nov 2, 2010
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  11. Irvin

    Irvin G.O.A.T.

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    I do not think I am missing the point, and the answer is maybe. It would depend on a lot more than time. If I were stringing kevlar string it would not be 10% to 15% more it would be less than that. If I were stringing nylon, maybe somewhere in that range.

    I never said that a lockout would string the same as a constant pull when set to the same tension.

    Irvin
     
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  12. Irvin

    Irvin G.O.A.T.

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    ^^ 'mad dog1' I agree with you completely. I do think that constant pull is better and that you will get more consistent results. What I do not agree with is that when you string with a lockout you should raise the tension by a fixed %. Most strings are different and unless you know what you are doing you will mess up always raising the tension by a fixed amount.

    BUT, getting back to the OP's problem - If you have a lockout stringer and you are accustomed to the job it does when strung at 45 to 48 lbs one can't arbitraily say on a constant pull that will equate to 42 pounds. It depends on a lot more than the time it takes to clamp the strings.

    Now is the horse dead or shall be beat it some more?

    Irvin
     
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  13. vkamphonephong

    vkamphonephong New User

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    Yeah, I agree with you here. It also depends on the type of string.
     
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  14. mad dog1

    mad dog1 Hall of Fame

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    agreed. i definitely didn't mention this in my 1st post. i think i kind of alluded to it in my previous post above.

    i agree with you again. since the OP made no mention of changing strings, i made the assumption that all things were equal other than the machine when the OP got his racquet restrung. but you're absolutely right. the type of string is another variable if the OP changed strings.
     
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  15. vkamphonephong

    vkamphonephong New User

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    Lol, I think the horse has been beat to death by now :)

    This is what I'll add. The reason why I originally bought a stringer is because everywhere I go, the job is different and I don't like inconsistency between one stringer's job and the next when I ask for the same thing. Maybe OP should consider getting a cheap machine...
     
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  16. struggle

    struggle Hall of Fame

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    if you have 2-3 rackets (same) you can easily enough experiment
    and get the 2 machines/stringers/shops doing closely similar
    jobs for you.
     
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  17. Irvin

    Irvin G.O.A.T.

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    If you have a Wise tension head you can pull tension in the lockout mode and watch to see the tension drop in say 10 seconds. Then you switch back to constant pull and set the tension to where it dropped to.

    Irvin
     
    #17
  18. ps2dcgba

    ps2dcgba Rookie

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    WOW!
    Thanks for posting guys!!! That is alot of info to digest, lol.
    Unfortunately I cannot get my own stringing machine, coz I am located in Asia, and I heard that a electronic machine will cost me at least USD7000-8000. (I did the conversion for you guys). I am a social player in my very late 30's.

    Someone mentioned my strings, the strings I am using on all my rackets, which is the same type model racket, Asian Wilson K6.1 tour with Signum Pro Poly Plasma 1.23.

    I didn't know there would be such a difference, and to think if by using a 'lockout' machine to string I may not be getting my requested tension of 48 lbs, but may be 38-42lbs....though I am very used to this low tension, it was very surprising when I tried the electronic machine , the tension felt very high than what I am accustomed to....I think with the lockout machine, the tension could be around 42lbs, I think I will send my racket's to the electronic machine and ask for 42 lbs and see if there is a difference, for experimenting hehehe.

    I'd like to thank all those that posted, you guys are the best, thanks tt-warehouse!
     
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  19. dgdawg

    dgdawg Professional

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    ....too funny! Can anyone say: talking in circles?.....
     
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