I think I have had a rant about this app before. It used to work well for me a while ago, tension readings directly after stringing were usually within 0.5lbs of the tension I strung at. I have recently decided to start using the app again today and the readings directly after stringing are about 4-6lbs off. I calibrated my machine yesterday (Wise 2086 head, calibrate with a Wise 2090). I re-checked the calibration again this morning and all was bang on perfect. Today I have strung 4 different rackets all with different types of poly string. I have triple checked the values on the app (racket pattern, head size, string gauge etc) and the readings are wildly all over the place directly after stringing. I have deleted the app, re-installed it, done the readings in a 100% silent room, used various tools to do the ping test (spoon, screwdriver handle), closed down all other background apps, changed the sound analysis and its all. I have done everything correctly and i still cant get this app to measure the tension as it should be. I think this app is good for one thing only and that is to measure tension loss between different times, not ACTUAL tension. Waste of time.
Racquet tune app tension readings after stringing
- Thread starter LHM
- Start date
jugheadfla
Semi-Pro
I have to agree with you, the RT app is crap. I have found it to be all over the place. The parameters that you have to choose from are so vague and the fact that just changing one parameter slightly has such a big affect on the reading makes me feel that its not even close. There is nothing that really defines the parameters either, like 'Stringing' for example. I have no idea how tight I string, as compared to what? And the parameter changes the reading drastically! The String type parameter is another one that can cause a drastic change in the reading. It says it is based on the density of the ingredients, but how are you supposed to know that? Is it referring to stiffness? I have no idea. I'm done with the app, its pretty useless. I have 2 16x19 PS Gen 3s that I string constantly at the same tension with the same string. When I ping them they sound identical. When I measure them with the app with the same parameters, they are about 4 lbs off. Not possible. dump it.
Znak
Hall of Fame
100% I've stopped entering string values now, just use it to monitor tension loss. I've tried to reach out to the developer a few times (and even the creator who keeps deferring me to the dev) to report bugs and app suggestions to no avail. Maybe I'll just have to make an app of my own hah.
ive found it utter useless recently. it used to work a treat for a while, then stopped using it, then i came back to it recently, all upto date, and its miles out. I just did another racket just now, strung at 52lbs, app gives a tension of 60lbs!!!!!!!!!!!!! I got my calibrator out and checked it against my machine, machine is matched upto the calibrator to within 0.3lbs. App is useless.
funnily enough, it was the RF97 i just strung at 52lbs and the app was showing it as 60lbs! All string factors, racket head, string pattern etc was correct.
just goes to show how inconsistent and unreliable the app is then really.
I have 2 RF 97. One was strung recently at 55 and the app showed 55.3. Tension loss has been normal. Probably the string factor is incorrect. I use weight based ones not sound based. These are all over the place.
Znak
Hall of Fame
Never heard, is it this one?
This one.Never heard, is it this one?
Tourna Stringmeter | Tennis Warehouse
www.tennis-warehouse.com
Tennis Vibes Android only?This one.
Tourna Stringmeter | Tennis Warehouse
tennisbike
Professional
Off Topic: This is kind of interesting read since I was used to people bashing how useless SM is while praising RT. Now I am seeing the flip side of the coin. At the end of the day though, I think the user simply need to figure out how the device can utilize to provide some useful information. Plus of course recognize its limitation and knowing what the information actually means.
From a non-user of RT, I would think one can still be used to track string bed property over time. Essentially it is simply the change of frequency over time.
For a more detail view of the string bed over time, I have been measuring 16+19 or 18+20 reading over time. The trend is actually pretty interesting, I thought.
From a non-user of RT, I would think one can still be used to track string bed property over time. Essentially it is simply the change of frequency over time.
For a more detail view of the string bed over time, I have been measuring 16+19 or 18+20 reading over time. The trend is actually pretty interesting, I thought.
D
Deleted member 369227
Guest
If you bring three identical racquets and string sets to three different stringers and ask them to restring at 55lbs/25kg, I guarantee that all three racquets will have slightly different stringbed stiffness ("sound").
Calibration differences between tension heads and even pace of stringing (e.g. how much time stringer let the tension head pull before clamping the string) will produce different stringbed stiffness. Consistency is much more important than being "exact" at the reference tension. In other words, look at the tension as a parameter/setting, not as an exact value. If you or your stringer consistently produce the same stringbed stiffness time after time, then you can increase or lower the requested tension next time if you are not happy with the tension.
The same is true for the Racquet Tune application - it should be used only to check the consistency between string-jobs and to track relative tension loss over time (in %). For that purpose, it is impeccable, in my experience. However, if you want it to show you "exact" tension, then simply fine-tune the string factor value until the app shows you the number you would like to see on the screen
Calibration differences between tension heads and even pace of stringing (e.g. how much time stringer let the tension head pull before clamping the string) will produce different stringbed stiffness. Consistency is much more important than being "exact" at the reference tension. In other words, look at the tension as a parameter/setting, not as an exact value. If you or your stringer consistently produce the same stringbed stiffness time after time, then you can increase or lower the requested tension next time if you are not happy with the tension.
The same is true for the Racquet Tune application - it should be used only to check the consistency between string-jobs and to track relative tension loss over time (in %). For that purpose, it is impeccable, in my experience. However, if you want it to show you "exact" tension, then simply fine-tune the string factor value until the app shows you the number you would like to see on the screen
LOBALOT
Legend
I think the big issue is the RacquetTune allows anyone to enter string factors. From what I have seen the string factor along with the tone produced are the only factors in determining the calculated tension and with who knows who uploading a factor for a particular string and then users pulling them down the values get out of whack.
For example, if you have seen my posts lately I have been stringing a lot of 16L Hyper G lately. I have found the string factor for 16L gauge to be completely messed up and just needs to be dumped and reset from scratch on the online database. However, the 16 gauge works great for 16L string!!! I am usually .3 or less one way or the other from the reference tension when I use the 16 gauge string factor for my 16L string. I wonder if people don't know the difference between the two and just add values willy-nilly.
Meanwhile 16L ALU Power Rough is spot on so whoever it is.... Please don't mess up that String Factor!!!
For example, if you have seen my posts lately I have been stringing a lot of 16L Hyper G lately. I have found the string factor for 16L gauge to be completely messed up and just needs to be dumped and reset from scratch on the online database. However, the 16 gauge works great for 16L string!!! I am usually .3 or less one way or the other from the reference tension when I use the 16 gauge string factor for my 16L string. I wonder if people don't know the difference between the two and just add values willy-nilly.
Meanwhile 16L ALU Power Rough is spot on so whoever it is.... Please don't mess up that String Factor!!!
LOBALOT
Legend
I just checked the application "Questions and Answers" section. The only 2 factors the app uses to calculate the tension are the String Factor and the Tone. It does not use the string pattern, head size, etc. to Calculate the tension. It does use the tension, head size, and string pattern to determine the stiffness of the string bed.
Therefore, if you have a bad string factor you are going to get bad readings.
I think they just need to ditch the whole contributing factor part of the app. They should have a good handle on the correct factors by now and just have those available for download.
Therefore, if you have a bad string factor you are going to get bad readings.
I think they just need to ditch the whole contributing factor part of the app. They should have a good handle on the correct factors by now and just have those available for download.
Indeed the string factors contributed by users are all over the place. The ones provided by the app maker are accurate or very close. The ones measured by weight rather than by sound are the most accurate. With the correct factors, the app can be used to measure the tension quite reliably.
PS: I will usually choose the factor that seems more logical and input the value manually in the string selection.
PS: I will usually choose the factor that seems more logical and input the value manually in the string selection.
LOBALOT
Legend
That is great! How do you know who contributed it? From what I see, one enters the string manufacturer, brand, and gauge and the app returns the string factor from it's database. I do not see a way to specify to only grab ones contributed by the developer.
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You can just save the string with the incorrect factor, then change the value manually by clicking edit in the first string page.
I have observed for instance that a 1.3mm SG should be around 150 and a multifilament around 140. Any values that are too different are most probably inaccurate.
LOBALOT
Legend
Thanks, I have been doing that. I was just wondering if there was some way to use a value the vendor supplied from their measurement.
Thanks!
Irvin
Talk Tennis Guru
Sten told me once measured SFs are more accurate. I weighed the string for weight and thickness before stringing a racket to get weight per meter which I could use as the string factor. The problem with that is a 1.30 mm string could stretch down to a 1.27 mm string after tensioning so I adjusted the SF for tension and string.
IMO it is all mumbo jumbo anyway. Great stuff if you’re OCD and you feel the need to feed your disorder.
It’s difficult to find a tennis player who is not OCD. We all have our little obsessions
Ah, good point about the stretch post string vs gauge. Never thought about this in such detail though.
min any case, what is the difference for the tension checks for SF from 1.30mm and say 1.27mm post stringing?
Irvin
Talk Tennis Guru
I played around with string factors for a while, but it didn’t take long to figure out I was wasting my time.It’s difficult to find a tennis player who is not OCD. We all have our little obsessions
Irvin
Talk Tennis Guru
That depends on the string and tension. Assuming you have 12 m of 1.30 mm string that weighs 18 g. The string factor is Then (18/12) 1.5. When you string the racket the gauge drops to 1.27 mm so the string factor drops too. In this case it drops from 1.5 to 1.43. Measure a racket and drop you SF by .07 and see what happens.
LOBALOT
Legend
Hi Irvin, in the end doesn't it come to a wash though?
The mass can't disappear so if the gauge decreases the length will increase so the string factor will stay the same.
If however one started with 12m of the 1.28 mm of the exact same material the weight would have to be less and that is why the corresponding string factor would be less?
I guess what I am saying is you don't need to measure the string factor under tension but only before.
esgee48
G.O.A.T.
Sten defines string factor as mass (grams) per meter. If the string has stretched 3%, your initial string factor is now mass per 1.03 meters. To get the correct string factor, you now have to divide by 1.03. This is why Sten now allows you to pull tension on a specific length of string and back into a string factor. The old way was to stretch the string under tension, then measure the string factor. It does make a difference with stretchy strings; not so much with thick polyesters.
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Irvin
Talk Tennis Guru
You half right as the gauge deceases the length will increase. If you have 18 grams of string the longer the string the lower the SF.
Injured Again
Hall of Fame
Just use the same mains at the same tension with the different crosses and measure the whole stringbed. The one which maintains the highest overall stringbed tension will be the cross that maintains the best tension.
LOBALOT
Legend
If you want to identify which poly cross holds the tension best I would:
1. Search on this forum there are a lot of good suggestions for poly crosses
2. Check the Tennis University site for info on strings and recordings.
3. String a full bed of the poly and try it out recording tension drops.
Physically it is not possible to use RacquetTune to test just the mains or the crosses when you have a racquet with different strings in it.
1. Search on this forum there are a lot of good suggestions for poly crosses
2. Check the Tennis University site for info on strings and recordings.
3. String a full bed of the poly and try it out recording tension drops.
Physically it is not possible to use RacquetTune to test just the mains or the crosses when you have a racquet with different strings in it.
esgee48
G.O.A.T.
Regarding poly tension loss or inversely, tension maintenance; If you look at TWU database, they generally fall into 2 segments. One segment loses about 45 or more percent, which I label the non factory prestretched. The second segment is factory prestretched and generally loses between 20-30%. You can also manually prestretch any poly/copoly and it will perform similar to factory prestretched. Just make sure you manually stretch the length the same percentage for consistency. If you want a longer lasting poly cross, you should be using strings in that second segment. Best ones I see are 4G and RPM Team with some of the newer ones that have rubber in their composition. Also depending on tension, you could just use ZX, PEEK, and be done with it.
tennisbike
Professional
Unfortunately, on a strung stringbed, the tension of main and cross strings are inter-related. Bumping up one will increase the other. Plus the frame is another factor not to mention string pattern.
If you want to observe just main or cross, use StringMeter. You can measure just the 16 or 18 mains or 18 to 20 crosses.
I suggest that you do that 16+19 reading for the life of a string job and then multiple string jobs to get a feel of how mains and cross strings degrade over time. I have.
One big hole is most people's understanding is that the area on the string bed do not degrade uniformly. The impact area gets more degraded than the area around it. This is what I have been observing. If you want a consistent string bed, you might want to start with more even tension in the center. A less than "optimum" string job might already have the center "looser", thus will degrade even sooner. I think most people worry more about what string to use than how their string bed come off the stringer. Most do not have any way of measuring, only a "sensitive" hand.
Folsom_Stringer_Musa
Professional
You saying poly center mains (used poly as example) strung loose (40lb e.g.) will degrade faster than center mains strung at 58lb (e.g.)?
tennisbike
Professional
What I observed is that in general, the strings at the center would decrease in SM reading more than the reading not in the center. (I even suspect that the characteristics of ONE string is NOT consistent in the center main. Though I only observed this occasionally on some string bed.) This I believe is what lead to some to say the string bed became more lively or having trampoline effect.
Thus if you already have lower tension on the center mains, this uneven or lower tension center strings has already began off the stringer. Although in reality, lower tension string would not loose tension faster than higher tension string. (This last statement is the one and only truth that always is true regardless of string.)
tennisbike
Professional
In general, a tool can be useful if the user knows its use and how to use it. A particular user may find a particular tool useless. Do you know that the sharpest knife edge is also one that is most easily damaged in the hand of unskilled?
Accuracy is how far a value, say measured or calculated, is compare to a "true" value. The question is what is the "true value" in the measurement? The reference tension on the stringer or the "ideal tension" on each string? And each string, main, cross, 16/18 or 19, they are seldom under the same tension. So most people use one number, one tension, to represent the whole string bed. Then each string changes over time. So the question is what exactly do you want to compare? Next the app does a lot of math and use a lot of "fudge" factor to match the "reference tension. I personally have more faith in my stringer than these fudge factors. But then I realize the most fuzzy of all is my head.
My 2 cents: Figure out what the tool or app does. If what it does is useful to you then good. Else it is useless to you.
Accuracy is how far a value, say measured or calculated, is compare to a "true" value. The question is what is the "true value" in the measurement? The reference tension on the stringer or the "ideal tension" on each string? And each string, main, cross, 16/18 or 19, they are seldom under the same tension. So most people use one number, one tension, to represent the whole string bed. Then each string changes over time. So the question is what exactly do you want to compare? Next the app does a lot of math and use a lot of "fudge" factor to match the "reference tension. I personally have more faith in my stringer than these fudge factors. But then I realize the most fuzzy of all is my head.
My 2 cents: Figure out what the tool or app does. If what it does is useful to you then good. Else it is useless to you.
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