lower tension in the centre string?

[x_h]

Hi there,

So I bought a string meter to see what tension I got after restring. I did one today and find that it shows my string tensions in the center are lower than those around them, I wonder if there is something I did wrong when I restring？ For this racquet, I tried to tension them at 58lb, and it turns out the center 4 strings only got around 50lb, and the rest of them are at 58lb.

I restring following the steps shows in this video.

Thanks.

 

[Pumpkin]

Very interesting. The world of electric guitars may be able to shed some light on the matter.

On a guitar the distance of the string from one end to the other is called the scale length. Now the scale length of a Fender style guitar is I believe about 3/4 of an inch longer than a Gibson style guitar and for this reason you have to string the Fender significantly tighter to get the same pitch as the Gibson.

So my theory is that the strings on a tennis racquet in the middle end up looser because they are longer. They would have to be pulled at a higher tension to get the same "pitch" as the shorter outer strings.

 

[Rabbit]

I assume that's not you in the video . You don't indicate how you started your mains. I disagree that you should pull the center mains tighter. Reference tension is only a number. The real test of the string job is on court. How does it play? I would discourage tinkering with individual string tensions, it's mostly a waste of time. Play with the frame and decide how if the string job is acceptable. I'd bet a dollar to a doughnut that it is. You don't really care about pitch with a tennis racket.

 

[esgee48]

@Rabbit is spot on. The other option is to pull or repull the central mains for a slightly longer time since those strings will relax once you clamp. OTW just pull at ref tension. If using a LO, the strings will definitely relax, so pull tension again.

 

[Yamin]

I was finding that if I did 3 strings on one side before switching to the other, my center strings had much less tension despite not seeing any slippage. I now do two per side then go back to three per side for the rest.

 

[Jerry Seinfeld]

The center mains measuring significantly different tension that outer mains is definitely something that is attention worthy. Something is going on as this should not be the case. Next time you string make a video of how you string the mains. There is likely something going on that can easily be corrected and by correcting you will find greater consistency in your stringing going forward.

 

[Pumpkin]

I disagree that you should pull the center mains tighter.

I wasn't suggesting someone pull tension on strings at different tensions. I agree that would be unnecessary on a raquet and a pain to do. I was just coming up with a possible explanation as to why he might be getting different readings

 

[x_h]

Thanks everyone, that is all very helpful. So I tried strings one side each then 2 and 2. And pull the first few strings 2 - 3 times, it helped with better tension when off machine.

 

[tennisbike]

.. I bought a string meter to see what tension I got after restring. I did one today and find that it shows my string tensions in the center are lower than those around them, I wonder if there is something I did wrong when I restring？ For this racquet, I tried to tension them at 58lb, and it turns out the center 4 strings only got around 50lb, and the rest of them are at 58lb.

I am assuming that you strung yourself and you measured the 16 or 18 main strings with SM after stringing.
First keep in mind that the smallest unit on a SM is 5 lbs. So any reading you get is + or - 2.5 lbs.
I use SM regularly on all my sticks that I strung. And I observed a bunch of stuff but I will focus on your question.

I often observed a lower SM number on the center left or right, I forget which at this instance, probably because of the starting sequence/procedure and how my d/w tension head is at a slight angle to the center of the turn table/racquet mount.
If I string same tension across the 16 main, for examples, the center 4 or 6 ALWAYS came out less than the outside main, because the centers are longer. If you are OCD, you can check with SM before installing the cross strings and get another set of 16 numbers to observe without the effect of weaving.
Because I want to achieve a more even SM number, which generally gives a more forgiving stringbed, I use an JET/JayCee inspired method by dropping # 4, 5, 6 by 3 to 4 lbs, and the SM numbers are much more even.
Without going to a full proportional stringing or Sergetti, which requires measuring the string length for each string and changing pulling tension almost for every other string, I get a pretty decent/similar effect. Yes, I have used my own spreadsheet to calculate the pull tension for the proportional for comparison. They were good but I get nearly as good with this simple dropping 3 to 4 lbs on the side mains.

These SM number, center 12, came out of a recently strung Prince Triplethreat Warrior OS: 37, 37, 36, 40, 38, 35 | 38, 37, 37, 35, 38, 38. The pulled tension was from the center: 52, 52, 50, 48, 46, 46

I think the tracking/documenting your stringing practice and checking with SM is a good solid way to learn to improve one's stringing practice. Good luck!

There are good advices and opinions out there, but data and figuring out what the data says is priceless.

 

[x_h]

I am assuming that you strung yourself and you measured the 16 or 18 main strings with SM after stringing.
First keep in mind that the smallest unit on a SM is 5 lbs. So any reading you get is + or - 2.5 lbs.
I use SM regularly on all my sticks that I strung. And I observed a bunch of stuff but I will focus on your question.

I often observed a lower SM number on the center left or right, I forget which at this instance, probably because of the starting sequence/procedure and how my d/w tension head is at a slight angle to the center of the turn table/racquet mount.
If I string same tension across the 16 main, for examples, the center 4 or 6 ALWAYS came out less than the outside main, because the centers are longer. If you are OCD, you can check with SM before installing the cross strings and get another set of 16 numbers to observe without the effect of weaving.
Because I want to achieve a more even SM number, which generally gives a more forgiving stringbed, I use an JET/JayCee inspired method by dropping # 4, 5, 6 by 3 to 4 lbs, and the SM numbers are much more even.
Without going to a full proportional stringing or Sergetti, which requires measuring the string length for each string and changing pulling tension almost for every other string, I get a pretty decent/similar effect. Yes, I have used my own spreadsheet to calculate the pull tension for the proportional for comparison. They were good but I get nearly as good with this simple dropping 3 to 4 lbs on the side mains.

These SM number, center 12, came out of a recently strung Prince Triplethreat Warrior OS: 37, 37, 36, 40, 38, 35 | 38, 37, 37, 35, 38, 38. The pulled tension was from the center: 52, 52, 50, 48, 46, 46

I think the tracking/documenting your stringing practice and checking with SM is a good solid way to learn to improve one's stringing practice. Good luck!

There are good advices and opinions out there, but data and figuring out what the data says is priceless.

That is very informative, thank you for the input.

 

[MathieuR]

If you are OCD, you can check with SM before installing the cross strings and get another set of 16 numbers to observe without the effect of weaving

On even the most expensive stringers the head of a racket is compressed ~3mm after stringing only the mains.
And these 3mm affects the center mains the most; they are pulled to ref.tension, and after more mains are tensioned the head gets compressed.

But the good news: after stringing the crosses the compression-forces are balanced again, and the head gets back its original shape.

So I don't think it makes sense to measure the strings without the cross-strings