About 2 point mount, crank tension machine

Discussion in 'Badminton Stringing Techniques & Tools' started by Blitzzards, Jan 17, 2011.

  1. Blitzzards

    Blitzzards Regular Member

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    I'm recently going to try a different stringer than the one whom I am already accustomed to and have done some research and found out that this new one is using a [relatively simple] crank tension machine with a 2 point mount system, compared to my previous one who uses 6 point mount, ECP.

    My main issue is that I have been requesting tensions of 31 to 33lbs using ECP from the previous one and he delivers, perfectly nice and tight. From the various older postings I have googled here, it seems to me that the relatively simple 2 point mount machines are quite dangerous to work with, given my current tension. I have a few things which I'm pondering about now, would really appreciate everyone's help :)

    1. The racquet which I'm about to tempt fate with is a Panda Power T2, which according to Dinkalot should be able to withstand 30+lbs of true CP tension with no problem albeit provided that the stringing is done correctly nonetheless. But is it even advisable for me to ask 28lbs true tension with the machine? I personally would like 28x28lbs (even tension) since I'm using ZM62 but should I vary the tension to play safe? Depending on my luck I may even need to restring my AT700 next.

    2. When tensioning using the crank (assuming that it is calibrated properly), is there a technique to ensure that the product tension is at least spot on or even 1lb higher than a constant pull tensioner? I was thinking perhaps asking the stringer to double or triple pull on the crank so that the string has ample time to stretch to the true tension before lockout.

    On a side note, I have also found a different stringer who uses a 6 point mount ECP machine. But according to him he has never strung beyond 26lbs and firmly asserts that any racquet that is pulled to 30+lbs tension will implode even with his machine. He told me that he has done 28lbs once in a blue moon but will not offer warranty for the racquet (read: due to stringing or racquet mounting mistake) if it is higher than 26lbs. He even rebuffed my statement that any mis-mounted racquet will break regardless of the tension (speaking from experience I have a friend whose Ti10 2nd gen broke when he asked for 22lbs with another different stringer, that was a case of the "high noon disease"). The last thing is that with this second stringer, he became dumbfounded when I showed him my AT800OF which is currently strung with NBG95 at 32lbs ECP (which sounded "tingtingting" compared to the usual tensions he has done with the same string) by my last stringer.

    So is there a way for me to check if my racquet is mounted correctly (such that it is in equilibrium as what a 6 point mount is supposed to give) if I let any stringer do the stringing?

    Thanks in advance :D
     
  2. Mark A

    Mark A Regular Member

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    The trick to getting close to "true" tension with a crank is to pre-stretch the string before it ever goes into the frame -I do this every single time without fail.

    With regard to crank operation, doing double pulls is a bit overkill if you've already prestretched. The best way to work is to move the crank slowly until it locks, and then move the clamps as quicky as possible - both will minimize sag.

    The most important thing, though, is to have the crosses absolutely straight by the time the crank locks for them. When I pull crosses I'm moving the crank slowly with my right hand while nudging the crosses straight with my left, looking right down the line all the while.
     
  3. Blitzzards

    Blitzzards Regular Member

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    Mark, I understand your method of slowly pulling and stretching the string, but considering the time spent in slowly cranking the tensioner, isn't it faster to crank twice, both times to lock down at relative "medium speed" then clamp at the second lock down? I don't think I will have the time to do the prestretching as I find it necessary to preweave the racquet for the stringer as he doesn't use the Yonex pattern (this way I can "force" him to not use his otherwise non-Yonex pattern).

    Another thing is, is it advisable to do both the mains and cross at 28lbs even tension or should I vary a bit? Personally I feel that 26x28lbs feels significantly more loose than 28x28lbs.
     
  4. Mark A

    Mark A Regular Member

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    Preweaving to force your stringer to use the standard pattern - I like it:D. In the absence of prestretching, multiple fast pulls will, if you do enough of them, have the same effect as one slow one, so it's up to you.

    I always add two pounds for the crosses, but I've never done a "square" tension (e.g. 27/27) so I can't comment on the relative merits/ptifalls. For what it's worth, Kim Dong Moon's "upside down" racket - something like 30/28 - was noticeably rounder than an empty frame. Wish I could remeber which thread it was in...
     
  5. Pete LSD

    Pete LSD Regular Member

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    Double pulls will always result in a much harder stringbed than prestretched ones. There are two ways to double pull. One is to pull with the insertion of a flying clamp and the other is not to use one.
     
  6. Pete LSD

    Pete LSD Regular Member

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    Also, if you want the resulting tension closer to the reference tension, calibrate the tensioner so that the locked-out tension drops to your reference tension.
     
  7. Mark A

    Mark A Regular Member

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    ... which I did; by the time I have repositioned my clamps, the tension has dropped and landed on the "true" tension. Depends how fast you are with your clamp movements, but 3 seconds' delay is normally plenty.
     
  8. Pete LSD

    Pete LSD Regular Member

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    Whether you can do 28 X 28 is highly dependent on the machine you are using. The average machines out there require adding at least 2+ lbs (6.45%) on the cross.
     

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    #8 Pete LSD, Jan 17, 2011
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  9. Pete LSD

    Pete LSD Regular Member

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    I would disagree with how fast one clamps with stopping the drop in tension. The locked-out tension drops no matter how fast one clamps anyway.

     
  10. Pete LSD

    Pete LSD Regular Member

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    Depending on the tensioner, a calibrated tensioner will briefly push tension above the reference by three pounds before lock out. After lock out, it takes sixty seconds to drop down close to reference tension.
     
  11. Blitzzards

    Blitzzards Regular Member

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    Pete and Mark, thanks for the insights.

    From my experience, I have almost always asked for "square" tension on the main and cross strings when I do 30lbs and below and for 31lbs to 33lbs I usually ask 1lb extra on the cross string as I personally believe the mains are holding very tight at such tensions and there is a need to pull slightly tighter on the cross to get it to settle at my reference tension more effectively (although I think this is only placebo effect but it works for me). However that was for a 6 point mount machine.

    As for the 2 point mount machine which I will be challenging now, is it still advisable to do 28x30lbs to bring the frame back into shape due to the lack of side supports (will the frame actually hold without being overstressed and damaged)? Will the effective tension then be higher than my reference tension of 28lbs (thus putting the very fragile ZM62 in jeopardy)?
     
  12. CovinaStringer

    CovinaStringer Regular Member

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    I have a Wise 2086 Pro tensionhead. When I got my unit back from factory service, I had forgot to set the Constant Pull function. Thus resulting in Lock Out mode. When I pulled a regular syn gut at 60 lbs, it reached 60 lbs then dropped to 54 lbs within a few secs. It's about a 10% loss in tension for 17 gauge string. For badminton string it might be even more.
     

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