Hi, The guy who does the stringing of my racket is unable to string the topmost cross string till the hole where Yonex original strings are. He does it till one hole lower. The reason is that the clamp he uses to hold on to the strings is not small enough to go into the small space left between the racket frame at the top and the topmost string. Please let me know if there is a way to get over this problem. Are there smaller sized clamps available? Is there a specific technique to string the topmost cross which this guy probably is not aware of?
As I metioned in the other thread, wider clamp with large mount pad (around pole) is a total nightmare for the top cross string. Myself mainly use Yonex flying clamp and Klipper M140 machine, and this combo does give me trouble for particular rackets (i.e. old cab rackets). The only way i can think, is to get narrower clamps just for the top cross. I have 2 original flying clamps coming with the machine, which is a good solution for the above issue.
LB, Just to add to your advice. If you just need 1 small clamp for the top, try PN-3091 from Eagnas. http://www.eagnas.com/tools.html It is same as the Klippermate except pn-3091 is diamond-coated. I was stringing my NS8K last night, I used a 6pt machine and it was not an issue. However, I do see it as an additional issue for M140 on the cross starting knot. Since the starting knot is on A5, it is covered by the holding pad on the top. This will be a problem from AT800 and NS7000 also. LB, any good idea beside a starting clamp?
I usually start the cross in the middle (using 4 knots / 2 pieces method), rather than the top. Therefore, as long as I have a smaller (narrower) clamp to finish the last cross, I am fine.
Sorry, I mean the top tie off knot is under the holding plates of the M140. Here is a story for you on the NS8000. Some stringer use 1 piece method on the NS. However, they string 22 cross through the T tide off for the main because is not used. Just a warning for those who use 1 piece method. It makes the overall racquet feel differernt.
What I do is the following: 1. Give 2lb extra when tension the last cross. 2. Use the machine to help tie off the knot. This way, it might not guarantee the very accurate lb on the last piece, at least, it can minimize the tension loss.
You can ask your stringer to pre-weave the first few top cross strings, together with a loose, untightened starting knot around the top grommet #5 or #6 (depending on if it is a Nano/AT 800 or another type), before he starts stringing. Once the mains are strung all he needs to do is to pull the first cross string at the top, and the loose starting knot will tighten. If he still cannot clamp the first cross string, then just add 10% higher tension and pull the second cross string, afterwhich the tension for the subsequent cross strings should revert back to the original tension.
Thanks for the advice all of you. One more question - Is it safe to string the cross strings starting fromtop and then going to bottom rather than bottom to top (as most people do)? I want to know from an "impact on the racket" perspective - Does it make a structural difference to the racket if crosses are strung top to bottom. I am told that the top portion of the racket is the weakest and hence the question. If it is safe to tighten top first and then move to bottom, then my problem is resolved without having to change the clamps. I can ask the stringer to begin from the top.
Yonex's method is to string the cross from the top first and then work towards the throat end. It provides the least distortion during stringing as the tensioning of the top cross strings would pass the stress to the much larger throat end side of the frame, which can handle stress better than the top of the frame.
Top-to-bottom method works well if you do low-to-medium tension, 20 lbs 25 lbs. Once you reach high-tension, it's preferrable to string from the middle, 50-50 technique. Bottom-to-top also work well at high tension. From my experience, the top part of the frame is weaker than the bottom part. You get more distortion if you start from the top. The area around the shared grommets at the top is greatly compressed inward at very high tension. I am in a similar situation as you are and am forced to work from top-to-bottom. Until I modify my machine I am stuck with top-to-bottom.
If you have a 2-point machine you can easily observe where the distortion is when tensioning the crosses. Let us say you use a cheap racquet to string the crosses from the top at 32lbs on a 2-point machine. The top part of the frame will compress inwards but it will not break. When you are into your first 3-4 cross strings at 32 lbs, you will see the bottom or throat end of the racquet frame (4-5 o'clock and 7-8 o'clock) crack outwards. The reason is that the major part of the stress has been transferred from the top to the bottom as you begin to press the top frame inwards and the stress goes down and outwards-bulging the lower frame outwards until it cracks. Starting the crosses from the bottom may compress the lower frame inwards less but the stress is then transferred towards the top of the frame, with an outward movement. The top frame is weaker than the bottom frame and may crack more easily from this outward distortion. However if you have a 6-point machine, this is a moot point as the protection of a 6-point system can handle almost all types of abuse you throw at it.
Stringing the crosses from the centre for high tension stringing is a good idea if you have a 2-point machine. But you cannot have a real starting knot with this technique. At very high tensions this technique loses a lot of tension, with two tie-off knots and no starting knot.
Actually, there is a way to maintain most of the tension under the 50-50 technique for both the cross knots, and main knots . No Awl and no counter tug of war are involved .
If it is just by increasing the last cross strings tension by 10%, it still loses tension. A double hitch tie-off knot plus 10% higher tension is not half as good as a real starting knot.
This is from laserfibre's site: Myth: 6-Point mounting with outside bracing provides the best racquet support. Fact: Not true. Typical 6-point mounting, using very narrow inside racquet supports at the 12 and 6 o’clock positions and 4 outside braces, is a reactive system. This means that the narrow supports at the head and throat can cause the racquet to bend and distort greatly when the main strings are tensioned. This created stress forces a need for additional outside braces to attempt to counter (react to) the distortion and in order to stop the racquet from breaking. 6-point mounting systems do provide adequate support and protection to the racquet during stringing. However, it is now believed by some that the stresses of repeated and frequent restrings of a single racquet on many 6-point systems may lead to premature fatiguing of the racquet and shorten its optimum performance life. Even though the racquet doesn't bulge out under the six-point system, it doesn't mean stress is not transferred to the bottom..
This is from a stringing machine manufacturer of one system expressing an opinion about other stringing machine manufacturers' different systems, including some of the most expensive and prestigious top name machines. There is even one manufacturer who says that its 2-point machines are the best, producing a type of distortion that ensures the longevity of the racquet. However, Lasefibre is just expressing an opinion. They should explain a little more.
Can you explain a little more on how this is done? I have a special knot tensioner/tightener tool that I bought from a stringing machine manufacturer that helps you to pull and tighten the tie-off knot with some measure of safety. But I find this falls far short of the starting knot and it takes up too much time.
This is appropriately what I do. Hopefully, the following description is clear to everyone. 1) Find a thin but very strong string 2) Tie a very small loop at one end 3) Insert the baddie string into the loop o the thin string 4) Take the unlooped end of the thin string and insert it into the loop to make a knot around the baddie string 5) do not hand tighten yet but make sure the knot is very close to the entrance of the knot grommet 6) now tighten by hand 6) insert the the baddie string and thin string into the knot grommet while holding the knot against the enrtance 7) Take the thin string and put it into the tensioner 8) Tension the thin string 9) Take the baddie string and tie the final knot 10) Untie the loop
Lets say the knot is at the top grommet 6. Where does the thin string come out from, the inner side of the frame at grommet 6 or the outer side, to meet the gripper of the tensioner?
