How a string loses it's tension?

We don't live in a physically ideal world so most badminton strings which are made of high polymer strands woven together will of course stretch, become longer and lose tension over time and after repeated impact stresses.

What you experienced is hard to quantify. What string and tension were you using?

Lastly temperature does not change the string tension a lot. The most I have experienced is 0.5lbs tension increase at a 20 degree celsius hall on a racquet strung at 28 degree celsius. The feel is not that significant anyway.

 

Bg65 is a pretty thick string. The thicker the string the more high polymer strands there are in the weave which when in tandem will cause a larger drop in tension compared to a thinner string. I have had Bg65 strung at 33lbs on an electric machine and it has dropped to 32lbs after about 6 months of usage now, even at such high tension of stringing.

What machine was your racquet done with?

 

IME rackets do play slightly "tighter" in colder conditions, but it's something you can adjust to very easily; over "normal" temperatures it would never be a full pound.

 

Are you using the same shuttles at colder temperatures? The shuttle would fly slower in colder temperatures which can make it seem as though the racket is strung at a higher tension. Not that I am saying you don't notice a difference, I am just curious.

I personally have never noticed a difference, when I can't hit a full court clear well it is usually a result of playing badly, which is usually a result of being tired or not warming up properly

One way to find out would be to try playing in a very warm environment, like outside (not ideal I know) in a tropical country and then go into an air conditioned hall and continue to play and see if you notice a difference.

 

My findings are based on string sound and net play only, but you're definitely right that it can't be judged on power shots because the shuttle speed would completely override any perceived string effects.

 

Hi Blitzzards, care to share how you measure the string tension of a strung racket?
Just curious how you can detect a drop of 1lb tension?

 

By having more than one of the same racquet, strung at similar tensions with the same string, and in this case one strung at 32lbs and then the one I mentioned strung at 33lbs. I can remember the hitting pitch (like when you hit the string bed with your palm to listen to the "ping") of both string beds (a natural musical ability called relative pitch) and the feel of the shuttle impact as I am sensitive to these high tensions

Unfortunately the 32lbs racquet has dropped to 30lbs now. It is also strung with BG65 and the feel of it now is totally different than when freshly strung

 

You don't need relative or absolute pitch if you have an iPhone and this handy little app called "Cleartune", which meausures the string frequency when you strum the stringbed.

From my experience, a 50 Hz change is equivalent to 1 lb difference on ZM67 strings. YMMV.

And yes, I notice a 1 lb change for every 5 degree Celsius change in the ambient temperature.

 

I prefer HTC to iPhone. There isn't one app such as that for my phone yet

Besides I had been trained in relative pitch and absolute pitch before when I studied music and I am only just applying my knowledge in this practical sense.

The highest change I have experienced is only slightly close to 0.5lbs with Bg65 at 5 degree Celsius change and it was almost not noticable.

 

wow. you guys are so amazing!!

does this mean that if you were given, say 5 pre-strung rackets at different tensions - same string, and you know the tension of one of them, you can use relative (or absolute) pitch analysis to determine accurately the tension of each racket?

 

As long as the 5 rackets are the same, then yes. Different rackets produce different sounds, even with the same string and tension.

 

Yes same rackets, same strings.

Let's say strung at 20, 22, 25, 27, 29 lbs - but you don't know what each racket is strung at. You won't even know the range of tensions.
So you say you can identify each tension of the racket? Accurate to 1lb?

Most of the stringers I know can only guesstimate what a racket tension is at - at any time. here we have a few people so confident they can identify racket tension accurate upto 1 lb.

..or is it accurate to 0.5lbs?

 

Not true.

The pitch is independent of different frames, as long as they're all isometric. It is only dependent on string thickness and temperature.

I have various brands of rackets with the same string and at the same tension, they all have the same pitch initially which drops by about 100 hz over a week with use.

If you don't believe me, just ask your stringer. They have the experience. As a matter of fact, they will always strum the stringbed after stringing a racket to check the tension.

 

Heh, asking stringers here would be the equivalent of asking to a five year old child. Stringers are so bad here I had to buy the machine and do it myself to get consistent results.

I do not have anything to verify the pitch of my stringbed, so maybe the pitch produced is about the same, but the sound produced is somewhat different. I know I get different sounds for different rackets with the same tension and string most of the time though.

 

^^

I feel bad for you that you don't have any good stringers you can trust. You should try moving to Vancouver or Toronto sometime.

 

I have myself as a stringer now, and I've been doing a good job according to people I string for

It was a good investment since I tend to break strings pretty often.

 

In that case, wait till you string about 200 rackets before you can properly consider yourself a good stringer.