Thread: 2LBs Cross Failed
09-30-2009, 12:19 PM #1
2LBs Cross Failed
I don't know if I'm doing it wrong, but every time I string 2 LBs higher for cross, the racket expands vertically. It makes the racket look very unproportional. This happens with every racket I string.
Yes. I made sure the racket is tightened to the supports and it didn't "warp" until I remove it from posts. And no, the racket is not cracked or damaged in any way before I string it.
I think for proportional appearances, I would do 1LB across instead of 2 or 10%.
09-30-2009, 12:40 PM #2
What machine are you using? What tensions are you stringing at?
09-30-2009, 01:03 PM #3
I'm using the Alpha Axis Pro stringing machine, hand crank. I do have a fish scale that I deliberately took my time to make sure the tension is correct. I don't go by the marking measurements from the machine. Even so, at 21/23 lbs or 22/24 lbs, the racket doesn't not hold its original shape. I'd like to believe 2lbs or 10% is correct, but it's not happening.
09-30-2009, 01:11 PM #4
Are you saying the frame lengthened and narrowed after the string job? The rule of thumb is 2 mm or less longer than original length. Have you compared your strung frame to an unstrung one?
09-30-2009, 01:18 PM #5
1) where are you in US?
2) can you move the 4 side mounts closer to the N/S posts?
3) can you adjust the n/s post closer w/o over extending the n/s adjustment arms (the thing attached to the yellow pad).
4) You realized this is a tennis only machine right?
09-30-2009, 02:54 PM #6
In fact, I've made a comparison with another racket that strung at 23/23, the frame is much more symmetrical compared to my 21/23 strung racket. It is not a true apple to apple comparison given that one racket is nanospeed 8000 and the other is nanospeed 9000X, but it shouldn't matter. I've strung Armortec, Arc Saber and the frame lengthen vertically with 2lbs cross. I'm not sure what 'secrets' you guys used to get it to be symmetrical, I'd love to know. I want to believe the 2lbs/10% method but my incapability is making it hard for me to do so.
I'm in Cali and yes, I do know I have Tennis Stringing machine. I also know when I reduced the cross tension to just 1 lb higher than the main, the racket has a closer form to being symmetrical. I'll take picture of my machine setup later tonight.
Here's a quick run down of how I mount my racket if you're interested. I first place the racket on the posts and let it sits freely as I slowly secured the North/South post. I tried to center it as much as possible before tighten it at the bottom of the turntable. Next, I turn the North & South mounting knob to hold the racket in place. I then slowly mount and secured the North/East arm and the South/West arm. Next, I slowly mount and secured the North/West arm and the South/East arm. I double check to make sure I have access to all the holes where the mount might have covered up. If everything is accessible and looks 'right'. I then tightened all the mounting knobs slowly and securely all around diagonally from each other like how you would when tighten the tire from your car. I don't overly tighten it as it might damage/crack the frame, but enough to feel secure when I try to move the racket. If it doesn't budge, I move on to stringing.
09-30-2009, 02:58 PM #7
This is a weird one. You know how to tighten all the supports correctly, so the racket isn't warped to begin with. I could point at a mis-calibrated tension head, but you've checked THAT as well! Only thing I can suggest is that you watch for the racket moving during stringing...
Can you post some pics of your strung racket compared with an empty frame so we can see how bad the distortion is?
09-30-2009, 03:03 PM #8
Seems like your doing it correctly. Please share pictures.
09-30-2009, 07:09 PM #9
how many grommets do you see between the two side supports on each sides? there should be around 12 to 13 of them.
well, picture worths thousands of words.
09-30-2009, 10:06 PM #10
My concern is the side support is not movable on this tennis machine. They might be sitting right at 3 and 9 o'clock position or very close. If that is the case, the racquet is very likely to warp since there is no hold down on N/S post.
10-01-2009, 02:33 AM #11
I hope I didn't screw up big time. I also had a chance to compared a friend's racket with same make/model, Yonex Nanospeed 9000X. His is a little bit wider (not shown in pictures below). The left racket was done at badminton gym 23/23, while the right one I did it myself.
On to the pictures....
10-01-2009, 02:43 AM #12
I see your point but what I'm confused is that if you increase the tension on the cross, it doesn't matter what support you have on the outside of the frame, the cross tension will squeeze the racket inward; hence, making the racket detour away from its original shape that you initially had it tighten/locked. If you don't want it to move at all, you would need the support from inside of the racket which it's not possible.
10-01-2009, 03:09 AM #13
From the pictures of your setup, it doesn't seem like there's anything horrendously wrong. In the picture of the two rackets, it doesn't really make sense to compare a NS8000 to a NS9000. You should show your friend's NS9000 racket (that you said was wider) besides yours.
Also, the NS8000 that you say was strung at your gym has an extra cross at the bottom. It's just something to note, I don't think it's that relevant to your current problem.
With all that said, you should trace an empty racket head with a pencil on a piece of paper. String it yourself with the +10% on the crosses. Then trace the racket head again and tell us what the differences are. If there is a "large" difference, then you may want to write out in detail all the stringing steps that you're doing (how you're starting the main and cross, how you're tying off, etc.).
10-01-2009, 05:27 AM #14
Hi dreamzboy, I've had the opposite problem where the racket gets shortened and crushed against the n/s posts but not this way round.
If you trust the tension being pulled is right, then is it possible that somehow the tension isn't staying in the mains so 21/23 is becoming say 19/23, allowing the crosses to overpower the mains and stretch/narrow the racket? Are the clamps slowly letting the string slip back when you release the tensioner or are the clamps themselves moving back on each release?
10-01-2009, 07:11 AM #15
I believe I found your problem. Your racket is not centered optimally. This is due to the north/south centering pieces (the yellow plastic pieces) being off: the north one is too high. The south one is adjusted accordingly to fit taut once you center the north piece.
To solve the problem:
1) move your top/north centering piece (the yellow plastic piece) down/south 1.00". You will notice all your side supports now shift and mount the racket 1.00" higher (up the frame) then they are now, which is what you want.
2) Now move your bottom centering piece to be taut.
If you run out of room on the south centering piece, you may need to adjust the whole physical post down a bit.
The key is to adjust the center pieces and north/south posts (if needed) to make your racket frame mount about 1.00" higher (more centered) than it is now.
In stringing, the problem is almost never the bottom half of the racket frame, it's always the middle to upper half.
I hope this makes sense and solves your problem.
10-01-2009, 05:03 PM #16
I've read a lot of your posts and thank you and everyone else for your contribution in this dilemma.
I see and understand what you mean by moving the north/center piece (yellow plastic) down south by 1" to provide stronger support for the upper half of the racket frame. However, if you look at the picture below, by moving it down, by that much, you won't be able to do the last cross string at the very top of the racket. How would you go about this?
...let me try this method first to see if it gives me any issue.
By the way, the dimension of the rackets that I compared with my friend is noticeably different with just a quick glance. Given that, there's no need for further proof that my racket is 'deform'. Comparing it to an unstrung racket of the same kind just makes it worst.
10-01-2009, 07:53 PM #17
you need to move both blue n/s post back (towards the end of turn table) about 0.5~0.75in. Then extned the yellow support inward by that much. That will solve your problem.
By kwun in forum Badminton StringReplies: 361: 02-14-2013, 02:34 AM
By KinkySmasher in forum Badminton StringReplies: 2: 07-07-2012, 05:56 AM
By lalalala in forum Badminton StringReplies: 2: 10-15-2010, 05:50 PM
By Malaysianfan in forum Asian Games 2006 - BadmintonReplies: 30: 12-05-2006, 11:32 AM
By batrachian in forum Badminton Stringing Techniques & ToolsReplies: 6: 10-28-2006, 05:34 AM