2 piece stinging

abiriax · 2004-08-01, 14:07

Hi, i read in the stringing guide that you should start the crosses at the top of all rackets, because it reduces stress on the racket, is this true and what is the proof? I ask 'cause i use a prostaff tour and have been stringin one piece on it for ages with no problem. I think the factory string was a one piece also. Your comments please

Jens · 2004-08-01, 15:57

The bad thing is that you can't always see what's happening to the frame because it's happening below the surface. If the stress on the material is too high, the material gets weak. You only see it when it's too late and there's a visible crack.
Anyway, the deformation of the frame is smaller when you start the crosses at the top of the frame. The throat area of the racquet is more stable than the head so it inerts more resistance to the deformation of the frame.
Some racquet brands won't replace your racquet if it's cracked and they see that it's been strung from throat to head.

abiriax · 2004-08-01, 16:55

okay, that's fine, i'm just wondering if this is true, why don't the manufacutres recommend a two string method for the relevant rackets. I mean i've never ever seen anything from wilson about this. Also, i have another question, how high over the recommended stringing range could i go for a ncode 90 or tour 90. I'm thinking of stringing it at about 69lbs.

Jens · 2004-08-01, 17:35

I don't think the frame will be damaged if you string at 69 lbs. Should be no problem.

iznofun · 2004-08-02, 10:20

Hello everyone !

I've been stringing for 16 years and 10 years as pro stringer. About frame stress, I experienced 2 and 4 knots patterns and after several thousands of stringing with different machines (electronic, air, drop weight, mecanic, ...) it's obvious that 2 knots patterns are no good for the frame.

Why ? First, you can see a higher distortion of the frame when you string the first crosses especially if you go directly from the mains to the crosses
at the top of the head, much less if you begin your crosses from the bottom because the heart of the frame is structurally the tougher zone of it (source: Wilson racquet sports principal ingineer).

Two, when you use a 2 knots pattern, there is a big tension difference between mains and crosses. mains are strung first with no resistance but crosses must be strung going up and down of the mains and that creates a loss of tension of 30% at least. Then, crosses need physically to get tension back from the mains as balance phenomena. This is perhaps the higher source of stress on the frames.

Three, as example, ask Yonex ingineer about it. Isometric shape makes the frame more fragile to frame stress. That's why they recommand to string with a 4 knots pattern and to begin the crosses at the top of the head to avoid distortion after releasing the clamps.

Jay Cee · 2004-08-02, 10:51

Hi man,

that's an interesting posting, it is a real pleasure to find someone else who knows what he's talking about. Maybe you can give me a break for a while and answer a few of the postings on this forum.

I get the impression that the others ask the questions, that I answer most of them and that either the majority don't understand or don't care what has been written, because apart from Jaypro and DF, with a small exception for DanN nobody really gives a damn. What I don't understand is why someone asks a question and doesn't acknowedge the reply. It happens far too often.

Sorry Joe, you thank me regularly, but there again we seem to agree on most things, it's true that from you and Dirk I do get encouragements.

So Iznofun, I would appreciate a few days off, so GO fot it.

I will keep an eye on you,

Jens · 2004-08-02, 13:56

Hi iznofun, welcome on board!

Hey Jay Cee, don't be frustrated, you really do an excellent job here. But I understand if you want to take a few days off and I'll be really happy if you come back soon.

Jaypro · 2004-08-02, 14:19

give me a friggin break...a few days off....

abiriax · 2004-08-03, 21:47

great but our friend gave some conflicting information on the issue of where to start your crosses. He claims distortion is greater if started at the head rather than the throat, anyone care to explain?

Hawkeye2 · 2004-08-04, 08:43

Hi abiriax,

We can't explain why your friend thinks that the distortion is greater if the crosses are started at the head rather than the throat.

This is because we think (at least Joe,iznofun and me) that the racket distortion is greater when stringing the crosses from the throat to the head.

And there have been a lot of good explanations for that already.

Bye