RacquetTune - Maybe Some Factor Variances = Temp Variances???

I was just stringing a unique racquet someone at our club gave me I have seen written about here... A Wimbledon Eclipse Expert...

Anyway, while stringing it I was thinking about all the comments about the variances in RacquetTune String factors for a particular string/gauge. I am sure there are a lot of reasons for this including technique. However, I have a hunch that temperature would impact the string factor at the time it is measured. Just like when we play tennis in the cold we feel our strings are stiffer vs. in the summer.

If I am recording a string factor for a particular string/gauge and it is cold vs. the blazing heat of summer wouldn't I get 2 different measurements assuming everything else is done the same?

I would think that the variance would be significant if we can actually feel the variance when we play when the temperature changes.

I am not sure anyone can answer this question but I just wanted to see what you thoughts are....
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No, thermal expansion is minimal. Temperature only affects how much the string will stretch as you apply tension. You should be string in an area where the temperature is fairly constant. RT factors are all over the place because I suspect people do not measure the 1 meter length (that has been tensioned) to the nearest 1/10 gram. That's what the manual use to say. If you measure multi unstretched and compare to one that had been tensioned at 58#, the numbers are going to be very different. Now RT will calculate the factor if you tension the string, enter length, tension and ping the string. Works for non hybrids and hybrids. Still have 2 factors to enter for hybrids.

If you are saying tension changes due to temperature, you're right. But that's not the same as pulling the right ref tension when putting in the strings. You select 58#, you want to know you pulled close to 58# and not 53#. If you pull the 58# and the guy goes out and plays in 80 F weather, the strings are probably going to be too loose. It's his fault for not asking for 62 or 63#.
Please note, I am just sharing thoughts and know you have more experience at this than me but I think it comes into play in 2 areas. I believe the first I have seen in other posts that individuals believe there is an issue with.

1. The iPhone Screen Sequence from the Main Menu->STRING->ADD->Measure the String factor. One enters the Diameter, applies tension (30-45 lb), measures the length, and plucks the string next to the iPhone. As you state, temperature affects how the string will stretch and thus the variability in the String Factor captured. Note: After this is complete the returned String factor can be saved to the common Database for use by others.

I know there is the method to weigh and measure 1 meter piece of String etc. but I am wondering if the item above is creating issues.

2. Let's say the String Factor is perfectly captured on January 1 and representative of the String/Diameter/Gauge on that day (lets say I used the weigh/length method). As the seasons progress and temperatures vary and I measure a particular string using RacquetTune on the same racquet/tension after restrings I bet the Delta between whatever the racquet was strung at and the tension RacquetTune returns will roughly correspond with the seasons as the measurement relies on plucking (stretching) of the string and the sound produced and as the seasons progress the temperatures vary.

I know we are supposed to be doing this in a controlled environment but these values are shared across a multitude of controlled environments. This would explain why folks say in Ecuador with the A/C blasting and feel it is a comfortable 80 degrees inside in their controlled environment and someone in Alaska with the heat blasting and it is nice and toasty at 72 degrees inside their controlled environment indicate they are getting mixed results.

I am seeing this trending in the delta between strung/measured tensions with the seasons with my racquet/string setup. I know it could be poor string jobs on my part but the trending is hard to ignore and interesting to note. I want to continue to capture information and perhaps I will share it with you when summer and outdoor tennis returns.

Thanks for all your help!
Temperature will affect post stringing RT readings. Your reading will be affected by the amount of tension loss due to play. At higher temps, string will stretch more, lose more tension. That is not the stringers' issue. If you want him to remeasure the RT factor, that will be $100.00 please. He needs to replicate what environment you played in to get the right RT factor. That's trial and error. He may need to have a piece of string that is on the frame. He is responsible for putting in the tension you requested. I use RT primarily for checking tension off the machine. If I am fractionally off, Good! If I am 5# off, Not Good.

If the customer comes back and ask for a RT check or complains that tension is too loose, I will ask him how many hours, yada yada. Normally, they've played too many hours with the current string. I tell them to acquire RT and I will provide them my string factor. Most that do, just want to use RT for relative tension loss, not what was lost from the original stringing.
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