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arnz
01-23-2006, 06:42 PM
OK I always believed that stringing low tensions (50's and lower) made the racquet more powerful and more forgiving for the arm, and stringing high 60's and above is good for control and spin.

Now some of you are saying that stringing low doesnt really do much good for the arm and doesnt noticeably affect the characteristics of the string. And to top it off, that stringing low is not going to produce more power, it just feels that way because the ball goes deeper. HUH???

Can somebody give me the last and final word on this please....THE TRUTH SHALL SET ME FREE:p

If there is no difference, I'll just string all my racquets at 40 lbs and save the racquet from stress

Masamusou
01-23-2006, 06:56 PM
You will get as many different answers on these as you will posters probably. Some believe higher tension gives better control and better spin, others say the other way. It depends on a number of factors, none of which are likely to be isolated to determine the true cause. String type, tension, racquet, style, etc. My observations have been that players with western grips who use a lot of spin usually prefer higher tensions, whereas I use a semi-western grip and hit flatter, prefer tensions in the mid 50s. Again, it depends on the string, racquet, string pattern, etc. The general rule is that higher tension gives more control and lower tension gives more "power". I laugh at the stringer that tells the ignorant customer that usually. Are you really going to notice a dramatic difference in spin by lowering tension 8 pounds? Probably not. It will be slightly different, but I believe some of the studies show that lower tensions don't really give more power, it alters the flight and generally goes slightly deeper. Again we are talking VERY small differences. Unfortunately, I don't think there is a "final word" as far as tensions go. It's all relative to each individual. There are people like me that prefer flexy, 18x20 patterns in the mid 50s, and others who can use the same racquet and prefer tensions in the mid 60s. It's an individual thing. You really just have to test out and see what is best for you. A good stringer can usually help you with a start if you give them enough information, but as a rule that fits everyone, I'm pretty sure there isn't one.

Midlife crisis
01-23-2006, 08:56 PM
OK I always believed that stringing low tensions (50's and lower) made the racquet more powerful and more forgiving for the arm, and stringing high 60's and above is good for control and spin.

Now some of you are saying that stringing low doesnt really do much good for the arm and doesnt noticeably affect the characteristics of the string. And to top it off, that stringing low is not going to produce more power, it just feels that way because the ball goes deeper. HUH???

Can somebody give me the last and final word on this please....THE TRUTH SHALL SET ME FREE:p

If there is no difference, I'll just string all my racquets at 40 lbs and save the racquet from stress

I assume you're talking about the previous thread, and if so I'm not sure what you hope to gain by starting this one, since everyone will say what they said there.

Just in case you're not talking about a recent thread, here's an article by RSI that describes the relationship of tension to ballspeed:

http://www.racquetsportsindustry.com/issues/200502/200502strings.html

No one is saying that you should string at 40 lbs. What you should do is string at a level that gives you the consistency of stringbed response that feels right for you. What you should not do is string at low tensions for extra ballspeed, unless you're doing something like a pure serving speed contest.

Strings do not behave linearly elastically throughout the range of normal tensions, and different string materials behave differently throughout their elastic range. For instance, if you string gut up 10% tighter, it may be 10% less elastic for the same force. If you string it up 20% tighter, it may be 30% less elastic. If you string it up 30% tighter, it may be 60% less elastic.

If you take a different string, it may be 5% less elastic at 10% tighter, 40% less elastic at 20% tighter, and 100% less elastic at 30% tighter.

These two strings will give you a dramatically different stringbed response at different stringing tensions and through your range of soft and hard shots.

So far, the only standardized testing, RSI's string map, only tests at one tension and one impact force so there is little information to determine the range of elasticity of strings at various tensions and with various impacts forces. This information usually comes from actual experience, and someone like an MRT would be able to help you.

Micky
01-23-2006, 09:40 PM
Hola arnz,

I don't know what level tennis you play. You might even be a baby...or an old man like me. Every racquet comes with a plus minus suggested string tension. Higher for more control...lower for more power.

Since the companies that produce racquets have the resources to test the sticks...why don't you just follow their advice? For instance...if your racquet suggests 58 lbs plus minus 5, I am sure you will cause terrible stress to the stick stringing at 40 lbs...and as much as if you are stringing at 75 lbs.

"THE TRUTH SHALL SET ME FREE" :p

Don't worry about the truth...worry about the lies.:rolleyes:

Micky

Masamusou
01-23-2006, 09:47 PM
Hola arnz,

I don't know what level tennis you play. You might even be a baby...or an old man like me. Every racquet comes with a plus minus suggested string tension. Higher for more control...lower for more power.

Since the companies that produce racquets have the resources to test the sticks...why don't you just follow their advice? For instance...if your racquet suggests 58 lbs plus minus 5, I am sure you will cause terrible stress to the stick stringing at 40 lbs...and as much as if you are stringing at 75 lbs.

"THE TRUTH SHALL SET ME FREE" :p

Don't worry about the truth...worry about the lies.:rolleyes:

Micky

I really don't see how stringing a racquet 10 pounds BELOW the recommended would harm the frame structurally. The recommended range is generally a range of tensions that the frame plays with its designed characteristics. The 40 lbs of tension would not harm the frame structurally, but it wasn't designed to be played at that low of a tension. Like the recommended range is usually more of a range that the manufacturer states is the best range to get the characteristics that they designed the frame for. Take the Babolat Pure Drive as an example. The recommended range for the woofer grommets is in the 50s. They have said repeatedly that they could be strung at 65, but at that tension you lose the characteristic of the woofer grommets. Just like if you string too low on a PD you get a very different feel (I've hit with a PD+ strung in the 30s before). It wasn't designed to be played at that low tension so it's not within the "recommended range". The range is usually not a "structurally safe" range but more of a "keeping the intended racquet characteristics" range.

Micky
01-23-2006, 10:05 PM
Hola masamusou,

Do some studying of resonance in physics. Low frequencies can be as damaging as high fryquencies. The issue brought up by arnz reminded me of the bridge that collapsed over the Potomac river long time ago.

Micky

Masamusou
01-23-2006, 10:24 PM
Hola masamusou,

Do some studying of resonance in physics. Low frequencies can be as damaging as high fryquencies. The issue brought up by arnz reminded me of the bridge that collapsed over the Potomac river long time ago.

Micky

By that logic, the frame would simply break down after a few weeks once the strings had lost tension and dropped below the range. I can string my racquets at 3 lbs above the minimum and because of string elasticity and tension loss they will be below the minimum tension by the next day (strings lose 5-15% of their initial strung tension within 24 hours without hitting, in case you weren't aware). No offense or anything, but frames don't suddenly break down because people play with strings longer than a day.

nimxnooj
01-23-2006, 10:40 PM
there's a differce between 3#'s under the minimum and ~20 #'s under the minimum (assuming the average recommended tension is about 60). Try stringing a racket at 80+ #'s and see what happens. I agree with Micky on this one. I'm in physics right now and low frequencies do as much, if not more, harm than high frequencies.

Midlife crisis
01-23-2006, 10:45 PM
there's a differce between 3#'s under the minimum and ~20 #'s under the minimum (assuming the average recommended tension is about 60). Try stringing a racket at 80+ #'s and see what happens. I agree with Micky on this one. I'm in physics right now and low frequencies do as much, if not more, harm than high frequencies.

Sure, but this situation does not apply to tennis racquets. It may apply to bridges, where that swinging type of vibrational excitation can be enhanced by things like the wind, but in a racquet, where it operates fully within its elastic limits (unless you throw it against the ground) and, outside of the impact itself is not subjected to additional energy input, it just doesn't happen.

Micky
01-23-2006, 10:46 PM
Hola masamusou,

No problem. Remember I told arnz that I did not know if he was a baby or an old man. He might want to keep his very own stick for 60 years right? :rolleyes: anyways...the more dwell time the more time the ball spends in contact with the stick.

I know the way the strings loose tension. But if somebody wants to read some good stuff about it here is the link:

http://www.racquetsportsindustry.com/issues/200509/200509stringselector.html

I also found a good link with some macro pictures of some strings that I enjoyed:

http://www.***********.net/gallery.php?PHPSESSID=11d0a2c9fa76189a9fa4c7c439c9 6a56

Take care,

Micky

Masamusou
01-23-2006, 10:52 PM
there's a differce between 3#'s under the minimum and ~20 #'s under the minimum (assuming the average recommended tension is about 60). Try stringing a racket at 80+ #'s and see what happens. I agree with Micky on this one. I'm in physics right now and low frequencies do as much, if not more, harm than high frequencies.

I've already passed Physics at a premier engineering university, thanks. However, there is one probem I see with this logic. You would have to hit the exact resonance frequency consistently, over and over and over again in order to begin breaking down the fibers of the racquet which is made primarily to withstand force in the direction of hitting. Stringing a racquet at 80 lbs would structurally damage the frame along the axis perpendicular to hitting simply because it isn't designed to withstand that kind of force pulling inward along the outer edge of the frame. The actual process of stringing at 40 lbs will not damage the frame in anyway. Provided you hit the exact resonance frequency, the strings only vibrate for a short period of time (generally less than 1 second) whereas damage from low frequency resonance waves takes repeated and prolonged exposure as evidenced from the previously mentioned bridge. The sudden impact of the frequency was not responsible for its failure, the prolonged exposure to its particular resonance frequency was the main cause.

Micky
01-23-2006, 11:04 PM
Hola Midlife crisis,

I just edited my previous post. I meant dwell time not resilience. The impact forces are very high in tennis and with high dwell time in your stick eventually will do its damage. You have a sweet point in your stick...hit it many times and that will translate to prolonged exposure to its particular resonance frequency as well.

Micky

Masamusou
01-23-2006, 11:14 PM
Hola Midlife crisis,

I just edited my previous post. I meant dwell time not resilience. The impact forces are very high in tennis and with high dwell time in your stick eventually will do its damage. You have a sweet point in your stick...hit it many times and that will translate to prolonged exposure to its particular resonance frequency as well.

Micky

I know this wasn't directed to me, but I'll just say that's partially responsible for fatigue. It's pretty common knowledge that racquets fatigue, from the process of stringing, and also from the numerous impacts. It's just something that happens. That's a small part of why some manufacturers generally suggest replacing frames every couple of years (but mostly because they want to make huge amounts of money by coming up with a new "technology" every 6 months or so).

Midlife crisis
01-23-2006, 11:47 PM
Hola Midlife crisis,

I just edited my previous post. I meant dwell time not resilience. The impact forces are very high in tennis and with high dwell time in your stick eventually will do its damage. You have a sweet point in your stick...hit it many times and that will translate to prolonged exposure to its particular resonance frequency as well.

Micky

Micky,

If the dwell time increases and if the string tension is lowered, what this means is that the peak forces are significantly lowered. If you double the time the ball is on the strings, the averaged force will be halved. If you then string the racquet at a lower tension and in a range where the strings have greater elasticity, then you will again reduce the peak forces on a racquet by another order of magnitude. I think this greatly compensates for the possibility that the resulting frequency may be more damaging to a racquet.

By the way, graphite has basically an unlimited fatigue life. This means that as long as stresses are applied below the plastic limit of the material (meaning that the force doesn't permanently deform it), carbon fibers will last forever. What does break down are the epoxies holding the fibers together. These tend to break down due to microscopically localized forces of the kind that are more likely generated by high frequencies than low frequencies. A low frequency tends to apply forces over a large area, whereas a high frequency applies forces over smaller, localized areas. It's also why you can more easily damage a racquet by impacting it with something sharp, whereas a racquet will withstand someone standing on it and even bouncing on it without breaking.

chunlimeyers
01-24-2006, 01:27 PM
Thank you for these two links!!.. they helped me solve my problem, and thus, I will solve yours!!!..
http://www.racquetsportsindustry.com...02strings.html
http://www.racquetsportsindustry.com...gselector.html

The second link is FARR more important than the second for math purposes, as U will see!.. Last year I strung my wilson tour 90 with a drop stringer(klip) with head fibergel power 16 to 64 lbs and luxilom alu power to 62. i experienced great "feel' with the gut like head string, but had to move very wide on the baseline to get my my same repeatable power serve in the box. So, I went home, and restrung just the crosses(luxilom) to 74!.. And, I had the perfect string tension for my frame.. And, everybody is thinking, 64 mains, 74 crosses??(sure, I am crazy!!)... makes no sense and I will bust myframe.. However, I used this combo with much success all summer. And, now I know why.. here are the nos..:
Head FiberGel Power 16 Nylon 1.31 189 11.62
Luxilon Big Banger Alu Power Rough 16L Polyester 1.25 240 18.98
Luxilon Big Banger Alu Power 16L Polyester 1.23 242 17.13
The nos here indicate guage, stiffness of the string, and tension loss. The one to concern yourself is the last no, the 'tension loss" no after they took 200 seconds and then applied the force of a 120 mph serve 5 times. So, lets now do the math.. 74-18=56(crosses), 64-12=52 (mains)!!!.. So, just cuz I am NUTS, and wanted more control on my serve, did I end up, mathematically, with the most perfectly strung racquet I have EVER used!.. Perfect dwell time, control, spin, and power, with a string job that lasts from a month to three. Now, I am looing for more spin and power, and almost foolishly went back to stringing ultra low with luxilom combo(to get more power), and think back to when I had an all alu string job at 52/48, and, if U take 18 lbs out of this, U know how nutty this string job was!
Ok, so, what are the exceptioins?.. The pros use "constant pull" machines.. these might "pre-stretch" the string, thus, the tension loss is already stretched out, and why we see that fed uses 52 lbs of "tension'.. And, of course, people who "pre-stretch' their string on purpose(or companies). So, now, if I want more "power" and "spin".. according to the top link of those magic articles, this would only give me more 'depth".. might be great for my newly developed "window washer" strokes, but be disasterous adding a foot or two of depth to my already dialed in 110 to 120 mph serve!.. And, another "exception", if U, or the players U hit with, don't have a 120 mph serve, as the strings either may take an exceptionally long time to break into this sweet no they came up with, or, not at all!(lucky for me I don't have to worry about that one, but I feel could be another factor on why some people need to string very high, and some are content wiht lower string tensions, however I will let U guys argue about that one!)..
So, now, with these nos, I can switch the mains and crosses, or lower my tension, just using the model that the awesome racquet sport magazine set up for us!! And, I still won't worry about "pre-stretching" my strings, cuz that would only further complicate what now is made pretty darn simple! And, finally, even if, as most would say, the lowly klip drop stringer just never seems to apply as much tension, at least I will know how much string tension loss differential between strings to match them perfectly... Hope this helps, as my search is basically done with 3 racquets to now experiment with 2 pound increments either way.

Ripper
01-24-2006, 01:52 PM
Thank you for these two links!!.. they helped me solve my problem, and thus, I will solve yours!!!..
http://www.racquetsportsindustry.com...02strings.html
http://www.racquetsportsindustry.com...gselector.html

The second link is FARR more important than the second for math purposes, as U will see!..

Links not working.

chunlimeyers
01-24-2006, 02:52 PM
Sorry, tried to copy N paste links from previous posts, but didn't work: just check out these previous posts above b4 U read my post:
midlife crises post #3 link
Micky post #10 link

These are both posts from RSI(Racquet Sports Industry). Thanks midlife crisis and Micky for these awesome links!

chunlimeyers
01-24-2006, 02:57 PM
sorry, needed to copy from actual site, these should work:

http://www.racquetsportsindustry.com/issues/200502/200502strings.html
http://www.racquetsportsindustry.com/issues/200509/200509stringselector.html

Gaines Hillix
01-24-2006, 06:01 PM
Chunlimeyers, good observation. It's terrific that this worked well for you. However, your theory compensates for tension loss, but not for stiffness of the string. This setup may be too stiff for some people because the poly crosses are going to be stiffer than the mains to begin with and will be much stiffer with your method. It may also void the warranty on the racquet to string the crosses that much higher than the mains. Needless to say, 74 lbs. is outside the recommended range for 99.9% of the frames out there and may damage thin, flexible frames like a Head Prestige.

Micky
01-24-2006, 11:17 PM
Hola chunlimeyers,

You are welcome. Now...if they could just test the Babolat Duralast 16...:(

Micky