Why do racket manufacturers recommend a 2 lb difference in tension between main and cross strings? I've tried it three times now on new Yonex TiSwingPower rackets, and in all three cases the rackets performed far worse than when the rackets were strung with even tension throughout. You can actually see the racket heads become narrower and certainly the sweet spot becomes smaller. The rackets may have been designed with the 2 lb difference in mind, but they certainly don't perform as if they were.
Iso heads must be strung with a 2 Lb difference because it is in a sqauer shape.if they string it the same tension then the racket would gave in sooner or later.but oval heads can be strung at the same.
You should string with 2lb difference, because the head of the strung racket would have a slightly deformed shape compared to an unstrung racket otherwise. When you string a racket, you start with the main strings, what causes a significant deformation sideways, because the are no cross strings to stabilize the head. When you begin to string the cross section now, the racket head allready is a kind of stabilized by the main strings, so that you need to string the cross section with a higher tension to bring the racket head back to its original shape. That's quite important for the durability of your racket especially if you tend to play with higher tensions. Best way to check if your stringer has done a proper job is to compare the racket head shape of the strung racket with an unstrung one of the same model. Personally I find no difference playing a racket strung with that difference compared with one which is strung overall with the same tension.
Most of the string machine have 4 or 6 clamps to hold the racket in shape before one pulls the tension on the strings. The racket should not be released from the clamps before both main and cross strings being tensioned. There should not be a matter change frame shape when you pull the mains and reshape the frame when you pull the cross afterwards. If the shape of your racket being changed, change your stringer at once. Even with hand-restringing, a supporting bar with adjustable length should be placed inside of frame before the mains being tensioned to keep the frame in shape. But why there should be a 2lb difference between the mains and crosses? I don't exactly know. According to tension/length relation, the tension of mains (longer) should be 2lb higher rather lower than the crossed because with the same tension, the longer a string is, the more stretched it can be on an impact. I asked several professional stringers, they simply anwsered that the difference is recommanded by the manufacture. I don't think it is a good enough anwser if I am making a living on stringing, don't you?
Hi Lao, just regarding the length of the strings, you're right, that the main strings should be strung 2lb higher. This is exactly what you do stringing tennis rackets. But stringing badminton rackets is a different thing, because they're not as solid as tennis rackets. Even on an advanced electronic stringing machine (like my babolat) with 6 fix-points a badminton frame "works" during stringing (of course depending on the height of the tension). Stringing with 18lb, it doesn't make a difference. But stringing with 26lb (for example) you need to work approximately with a 2lb difference to obtain the same head shape like unstrung.
On the Yonex site, they recommend for example, 22lbs cross and 20lbs. main. Who is right? The cross should be higher in tension or main be higher? Very confusing guys.
Dear Ovk, I trust your observation and experience. But does that mean you don't have a even tension string bed if your racket is strung at above 26lbs. Two implications: would be an even tensioned string bed more effective for both power and control, and is a round shape frame more logical to achieve that? My rackets have been strung at 24/24lbs in a 22x22 pattern. No problem so far t okeep the original shape, but not sure if I go higher.
