can any moderator help to edit the answer? need to change to my answer.. hee... we split the prizes...
hehe. so here is the 2nd measurement; [video=youtube;mHclmA7RPCU]http://www.youtube.com/watch?v=mHclmA7RPCU[/video] and the answer is: 15.12lbs
and with this, we have a winner, is he is: om4r_s, whose answer of 29.7lbs and 15.4lbs is the closest. only off by 3.35lbs. CONGRAULATIONS. honorable mention is maa2003 whose answer of 30lbs and 15lbs is off by 3.49lbs, merely 0.14 lbs from om4r_s. it was a close one. om4r_s, please PM me your address so we can send you the price. the NBG99 will be sent to you later this month when it is release. MBS will send you the prize directly. thank you everyone for playing this contest. we will for sure have more!
so... now that we have a winner... what does this mean in the real world when applied to stringing? that we're not getting what we paid for?!
Crazy results, i had a feeling it was going to be 10-15% loss per grommet pass, but yeah definately should be an eye opener to all stringers. It means that the starting cross shouldn't be pulled two at a time especially if you're going top down. At almost 50% loss, you're not going to have much protection against misshits. I've already remedied this problem ever since I noticed that the first and last cross always seemed looser.
Mental - from 30 lb to 15... now I'm really glad I always pulled the top cross direct. For those whose machines are strong enough to break the knot, even 2/3 of the target tension is better than a double-pull, it would seem.
the question is, does that matter? from the tension point of view, the side strings aren't really doing any real work to hit the shuttle. so 25%, 50% loss is almost a don't care. but for mishit protection, is it better to have a lower tension to give it more of a soft buffer, or is it better to have a higher tension to give it more support when the shuttle hits here?
i think for the last two mains (yonex pattern) is a double pull a good choice. @kwun: can you test what is on b12 when you pull at b10. it should be more than on the cross in that example, because there is less frinction. a pull on b12 is a lot of stress for the racket. maybe this is a good possibility to reduce the stress on the racket...
that actually brings up an interesting point. what does it mean by strong enough? isn't 30lbs = 30lbs? how is a machine stronger?
i just want to point out another thing. it is not as bad as it looks. the tension as measured is the tension outside the frame. inside the frame, the tension is going to be higher. the contest setup that way partly because it is much harder to measure the tension within the frame accurately. another point is that it is still pretty bad. even given the best scenario where we lose around 3 lbs going through the grommet, the tension on the 2pull is still at best 18lbs inside the frame. i too was a bit surprised by the difference, but given that the string has gone through 3 grommets and 34 strings, there is a lot of friction. the last point i want to make is that when we talk about tension between main and cross, we are actually comparing apple and oranges. there is a lot more tension loss on the cross than on the main. i did similar experiment on the main and without the string friction, the loss is only 1 lb or so on the single pull. the very last point is for people who do complete pre-weave both mains and cross. the tension you will get will be different than tension we will get if we weave and tension mains first. and then we weave and tension cross separately.
For a direct pull on the 1st top/bottom cross, what is the max tension you guys here have done? My personal experience is nothing more than 28LB be it using a commonly used tennis starting knot, Parnel + 2 half hitch or 3 half hitches. Seriously a direct pull on the starting knot is highly dangerous. One of the interesting methods i ve seen is using a starting clamp on b9 (for bottomup) and after doing a handful of crosses, pull the string from b9, clamp it and tie off at b6/b7. I have personally tried this once in 30LB on BG80 and it seems to retain tension well until you hit it for 2hrs and immediately get 2-3LB off.
You should talk to Pete about his Victor. 30 = 30 on any machine, I agree; I think by "strength" I really meant "speed", weirdly. I've only used the older (blue) Yonex machine, but that thing didn't hang around - got to the set tension a LOT quicker than my WISE at top speed.
