I was trying to get ngy99 at 26lbs with some prestretch on my racket. The stringer didn't know how to prestretch (yes I know I need to find a better stringer). The question I have is would increasing the tension to 27lbs give the same effect? And yes I am looking for some good stringer reccos in the Toronto /hat region. Please pm me if your a stringer or know a good person.
NBG99 is one of the best tension holding strings Yonex make. I prestretch mine but to be honest, it doesn't seem to make much difference. Whereas on strings like BG65Ti, it does seem to make a bit of a difference. If you can tolerate 27lb then I say go for it. All strings lose tension, but NBG99 retains it quite well. I'm currently playing with NBG99 on most of my racquets at 31lb and over the first few weeks it only seem to drop by a very small amount, perhaps 1-2lb. And then it settles quickly and maintains that tension for the life of the string.
Prestretch and extra tension have different effects: If the blue curve represents the default tension with no prestretch, the red curve shows what happens if you add 1 lb, and the green curve shows the default tension with prestretch. As you can see, presretch doesn't affect the steady-state tension - the horizontal limit of the curve - it just slows the rate of loss.
Now your picture makes some sense But all this is just based on theoretical calculations and not experimental data right?
Mainly based on experience, but I have taken some frequency measurements of string jobs as they have aged.
That graph is a nice way of understanding things. Thank goodness for the fanatically precise among us!
ummm... i suppose horizontal axis is time and 0 is when stringing is finished... so what does -2, -1 mean on that axis?
It means I couldn't be bothered to specify that the graph should start at zero time. Or what would happen to the racket if you took it back in time - up to you.
This another example from a Japanese stringer, who performed research on tension loss of NBG 99 Initial setup = 25 lbs Term of period = 16 days ps. : I don't understand Japanese language, and the above information is merely based on my personal / logical interpretation.
@clawhammer , if I am looking at the data correctly, it looks like the tension went from 100% right off the stringing machine to ~93% one day later, and 85% at day 8 and down to ~82% at day 16. The limited info seems to match the thought that one should let a freshly strung racket 'rest' at the very least one day and up to about a week before bringing out to play, due to letting the string and tension stabilize. @abans , as Mark A posted earlier, higher tension is different from pre-stretching to remove some elasticity. If you haven't yet, try posting in the regional sub-forums and ask there for a recommendation for a stringer. You might have better luck.
Interesting. I wonder what and how they monitor the stringbed tension? And I assume that also includes playing time too?
