Stringbed frequency to monitor string tension

Discussion in 'Badminton String' started by visor, Feb 27, 2013.

  1. craigandy

    craigandy Regular Member

    Joined:
    Aug 9, 2011
    Messages:
    2,363
    Likes Received:
    19
    Location:
    UK
    Yeah sorry just my poor humour, none of those rackets are nearly small enough to get my frequency up to yours.
     
  2. DarthHowie

    DarthHowie Regular Member

    Joined:
    Sep 17, 2003
    Messages:
    1,159
    Likes Received:
    183
    Occupation:
    Software Developer & Assistant Coach @ GBC
    Location:
    Toronto & Vancouver, Canada
    I would say i'm a slow weaver on the crosses, but i leave the wise tensioning like you do, but on every other cross when i weave 1 cross ahead. The other times i clamp and disengage the wise, flip the racket 360 (because the handle is obstructing me from weaving ahead during tension) and weave 1 ahead. That should negate the tension loss theory.

    Hope that didn't sound confusing.
     
  3. DarthHowie

    DarthHowie Regular Member

    Joined:
    Sep 17, 2003
    Messages:
    1,159
    Likes Received:
    183
    Occupation:
    Software Developer & Assistant Coach @ GBC
    Location:
    Toronto & Vancouver, Canada
    I got a few rackets to string to see how my frequency changes after at least 24 hours. Hope this helps.
    YY Arc Saber 10 @ 24 x 26.4 lbs w/ BG-66:
    Frequency: 1313 Hz -> 48 hours later -> 1248 Hz

    YY Arc Saber 10 @ 24 x 26.4 lbs w/ BG-66UM
    Frequency: 1315 Hz -> 48 hours later -> 1263 Hz

    How do those numbers measure up? still high? I'll post again when I get to string a racket with BG-65 since it is a good reference.

    I just shot a video of one of my string jobs. Hopefully i can put it up on youtube for you guys to analyze. It was YY Nanospeed 9900 @ 25 x 27.5 lbs w/ Victor VS-850 with a frequency of 1258 Hz.
     
  4. DarthHowie

    DarthHowie Regular Member

    Joined:
    Sep 17, 2003
    Messages:
    1,159
    Likes Received:
    183
    Occupation:
    Software Developer & Assistant Coach @ GBC
    Location:
    Toronto & Vancouver, Canada
    If any of you are interested, I posted a video of my string job in the stringing techniques forum here:
    http://www.badmintoncentral.com/forums/showthread.php/144221-VIDEO-DarthHowie-Stringing-a-Nanospeed-9900-VS-850-25-x-27-5-lbs
     
  5. visor

    visor Regular Member

    Joined:
    Dec 7, 2009
    Messages:
    16,400
    Likes Received:
    2,001
    Location:
    Vancouver, BC
    Comparing kwun's bg66um @ 26 lbs, his frequency right off the machine is around 1265 Hz.

    Whereas your 26.4 lbs is 1315 Hz, some 50 Hz higher. Taking into account half lb is 15 Hz, so your 26 lb would be corrected to 1300 Hz even... which is still 1 lb tighter than kwun's.

    Nothing wrong with that. And most people won't be able to notice 1 lb difference anyways. Perhaps your clients will like how their rackets don't lose much tension over time. :)
     
  6. DarthHowie

    DarthHowie Regular Member

    Joined:
    Sep 17, 2003
    Messages:
    1,159
    Likes Received:
    183
    Occupation:
    Software Developer & Assistant Coach @ GBC
    Location:
    Toronto & Vancouver, Canada
    When kwun references his tension of @26, is it:
    24 x 26
    25 x 26
    25 x 27
    26 x 26
    26 x 28?

    Thanks. Need to know the main and cross.
     
  7. visor

    visor Regular Member

    Joined:
    Dec 7, 2009
    Messages:
    16,400
    Likes Received:
    2,001
    Location:
    Vancouver, BC
    I believe kwun does the mains at 12% less than crosses.

    So his 26 lb is 23.8 x 26.
     
    #227 visor, Jul 4, 2014
    Last edited: Jul 4, 2014
  8. ucantseeme

    ucantseeme Regular Member

    Joined:
    Feb 21, 2010
    Messages:
    5,045
    Likes Received:
    2,382
    Occupation:
    Z-Force II
    Location:
    Z-ForceII
    @ DarthHowie

    I'm excited about your work. Can you explain how you ping the rackets to measure the frequency? I use Carltunbe, too and knock with the frame of another racket against the stringbed. Maybe their is a difference?
    I did this morning a 29 / 31 BG65 (10 % prestretched, proportional stringing for the cross) on one of my MX80 and measured only 1267 Hz directly after stringing. Maybe I'm too stupid to measure correctly or my jobs are really off. :crying:
     
  9. DarthHowie

    DarthHowie Regular Member

    Joined:
    Sep 17, 2003
    Messages:
    1,159
    Likes Received:
    183
    Occupation:
    Software Developer & Assistant Coach @ GBC
    Location:
    Toronto & Vancouver, Canada
    My method of measuring the frequency is exactly the same as yours. Ping the stringbed against the frame of another racket. I only started recording frequencies in to my database this year. I don't think 300+ data points is sufficient since some tensions are for only one string job. It's best to go with the average frequency for now and not the extreme min and maxes. I'll probably generate a new report at the end of the year when i have a larger sample size.

    Right now i can't make any conclusion about my data or anyone else's simply because there are a lot of variables: racket frame, constant pull (on/off), prestretch, supports, the stringer. I hope with time and larger sample size, the average frequency will be my "target" for consistency.
     
  10. ucantseeme

    ucantseeme Regular Member

    Joined:
    Feb 21, 2010
    Messages:
    5,045
    Likes Received:
    2,382
    Occupation:
    Z-Force II
    Location:
    Z-ForceII
    Generally speaking if we come to conclusion that the frequency is a dimension to measure string tension their shouldn't be so much differences otherwise this method is muck for measurements. So IMO their is a need for same conditions like same racket frame, same analyzer, same room, same main/cross ratio, same modi for the wise, identical machine and so on.
    I think that there is no frequency that tells you the exact tension. IMO I'm really off with my measurement, maybe we are all wrong.

    My default setup:

    PS3600 with a wise, fixed clamps, 10% PS, Chudek supports.

    My 29/31 job is a bit below of DarthHowie 27lbs job, if we use the frequency as reference. So I'm nearly 100 Hz of which is for my sight of view a huge difference and I don't think I do a worst job. I can't help but this measurement makes me crazy. Maybe this fixating on frequency is a dead end until we have the same equipment and same procedure to measure tension.
     
  11. DarthHowie

    DarthHowie Regular Member

    Joined:
    Sep 17, 2003
    Messages:
    1,159
    Likes Received:
    183
    Occupation:
    Software Developer & Assistant Coach @ GBC
    Location:
    Toronto & Vancouver, Canada
    I've been mainly using the frequency data as a reference to what a comparable tension frequency wise would be needed should my customer want to use a different string...(I'm aware the material of the string and its use: power vs control or hard vs soft will not make it an apples to apples comparison). At least recording the stringbed frequency is a great way of measuring tension loss which is something i definitely care a lot about.

    I figured maybe this is something of added value a stringer can provide to all levels of players when they get the common question "What string and tension do you recommend for me to put on my racket?"
     
  12. Gary Lim

    Gary Lim Regular Member

    Joined:
    Aug 14, 2014
    Messages:
    100
    Likes Received:
    3
    Location:
    Singapore
    Digging up this thread after reading through it. Very interesting results.

    Here's mine:

    VT03Tour | LiNing 01 @ 22lbs - 1050Hz (2 weeks, 3 plays)
    AR03Tour | LiNing 01 @ 22lbs - 1056Hz (2 weeks, 1 play)
    Carlton 3.9 | BG65 @ 22lbs - 1023Hz (2 weeks, 0 play)
    YY Isometric 500 | BG65 @ 20lbs - 1013Hz (1 week, 0 play)
    YY B560DF | Stock @ Unknown - 656Hz (8 years, multiple plays) - my "do you have a spare racket" pc

    The BG65 results are quite a ways lower @ 22 and 20 from the chart on pg. 13. I doubt my stringer is deliberately stringing it lower than requested so there does seem to be a fair margin of difference?

    Although, I did use a guitar pick to measure so I'm not sure if that changed the reading some.
     
  13. visor

    visor Regular Member

    Joined:
    Dec 7, 2009
    Messages:
    16,400
    Likes Received:
    2,001
    Location:
    Vancouver, BC
    BG65 is notorious for losing tension... perhaps your stringer forgot to prestretch it.
     
  14. Gary Lim

    Gary Lim Regular Member

    Joined:
    Aug 14, 2014
    Messages:
    100
    Likes Received:
    3
    Location:
    Singapore
    That might be it.

    Anyway, another to add, just strung this ytd:
    Nanoray 500 | LiNing 01 @ 23lbs - 1113Hz (2 days, 0 play)
     
  15. jerby

    jerby Regular Member

    Joined:
    Sep 3, 2005
    Messages:
    4,123
    Likes Received:
    32
    Location:
    EU
    I'm very late to this game, but I've installed th carltune app and decided to see how I do compared to other :)
    But wow I'm sort of off, compared to DarthHowie.

    Here's some of my data, I string 2p,top-down, on a Wise and use flyingclamps.

    Adipower Pro, bg80 at 29x30lbs (13x13.5kg to be exact): 1254Hz
    Adipower Pro, Adidas P Hybird 29x30: 1180Hz
    YY ZSpeed, bg80 at 30x31lbs (14x14.5): 1307Hz
    YY ZSpeed, bg80 at 31x32: 1343Hz
    Apacs Slayer 99, ZM62 at 26.5x27.5: 1259Hz

    So my frequencies are good deal lower than some others here, which is kind of weird because my tensions are quite equal to some rackets I strung (and got strung) at tournaments.

    When I put my Adipower bg80 (29/30) aside for a weekend I saw the tension drop 5.5% in 24h (1185Hz), and 6.1% after 56h (1177Hz) (3 days unplayed). Is that good or bad?
     
  16. DarthHowie

    DarthHowie Regular Member

    Joined:
    Sep 17, 2003
    Messages:
    1,159
    Likes Received:
    183
    Occupation:
    Software Developer & Assistant Coach @ GBC
    Location:
    Toronto & Vancouver, Canada
    I think the more important thing as a stringer is to make sure your tensions/frequencies are consistent. From replies in the forum..my initial frequencies are higher than most stringers. I warn new people i string for that my tensions feel about 1 pound more than others. I'm wondering if that's because i pull 10% more on the crosses...so 29 pounds for main...+2.9 pounds for cross. so 29 x 31.9. That may explain why it is higher.

    The chart i attached a while back is probably out of date now that i have more data points. My goal is to hit the "average frequency" for each tension and string combo. The Highs and Lows are for me to keep track of the extremes. I do notice that i get consistent frequencies for the same model racket, string and tension...and there is more variance once i introduce a different racket model. Maybe it's materials.

    Just want to repeat that the chart is more a guide for myself. I just hope it serves as a bit of a reference for others in the community. I will try to publish a more up to date one.
     
  17. DarthHowie

    DarthHowie Regular Member

    Joined:
    Sep 17, 2003
    Messages:
    1,159
    Likes Received:
    183
    Occupation:
    Software Developer & Assistant Coach @ GBC
    Location:
    Toronto & Vancouver, Canada
  18. visor

    visor Regular Member

    Joined:
    Dec 7, 2009
    Messages:
    16,400
    Likes Received:
    2,001
    Location:
    Vancouver, BC
    [MENTION=11821]jerby[/MENTION]
    Better late than never... :)

    Those frequencies are right off the machine? And the last paragraph is unplayed racket? In that case it is slightly lower than others. No prestretch?
     
    #238 visor, Dec 31, 2014
    Last edited: Dec 31, 2014
  19. visor

    visor Regular Member

    Joined:
    Dec 7, 2009
    Messages:
    16,400
    Likes Received:
    2,001
    Location:
    Vancouver, BC
    [MENTION=2950]DarthHowie[/MENTION]
    Hmmm... so if someone asks for 29 lbs, what tension do you string for main and cross? 29x32 or 27x29?

    Edit: Or 27.5x30.5?
     
    #239 visor, Dec 31, 2014
    Last edited: Dec 31, 2014
  20. DarthHowie

    DarthHowie Regular Member

    Joined:
    Sep 17, 2003
    Messages:
    1,159
    Likes Received:
    183
    Occupation:
    Software Developer & Assistant Coach @ GBC
    Location:
    Toronto & Vancouver, Canada
    28 x 30.8. Which is slightly higher than 29 average (29.5??)
     

Share This Page