Hey physics geniuses

[solomon707]

I know there are a lot of you on here more scientifically inclined than myself. Have any of you tried using a tensiometer (I was thinking of this one since I work at a bike shop) to measure string tension? Would it only be useful for measuring relative tension, since it's actually measuring deflection, or do you think its readings would be accurate on something like bass strings?

[bongomania]

What a tensionometer can't measure is how the string vibrates in actual use, and thus whether it will for example "sound focused" on the low B. That said, some string manufacturers do supply tension specs for their different strings, and that data is collected with some sort of tensionometer obviously, and many people find those data useful.

[solomon707]

I've seen some of those charts. I guess my question is more whether a tensiometer designed for use with bicycle spokes or in other industrial applications would provide accurate readings on strings.

[lposavad]

What will you do with the data once you have it? Unless you plan to mix 'n' match string gauges.
As bongomania said, many/most string manufacturers publish their tension data, which means poo when my singer asks me to detune a half-step...

[slyjoe]

Originally Posted by solomon707

I know there are a lot of you on here more scientifically inclined than myself. Have any of you tried using a tensiometer (I was thinking of this one since I work at a bike shop) to measure string tension? Would it only be useful for measuring relative tension, since it's actually measuring deflection, or do you think its readings would be accurate on something like bass strings?

It won't work because of the range of tension it measures. Bike spokes and bass strings are not close in tension - some quick googling looks like they are off by a factor of 4.

And like lposavad said, once you measure it what are you going to do with it?

[fdeck]

String tension is a simple function of the fundamental frequency, length, and mass per unit length. On a bass, the frequency is determined by what note you want to play.

In fact, I suppose that you could tune the spokes on a bicycle by plucking them and listening to the note.

I never had rims that started out circular, so I end up adjusting the spokes so the wheel runs true.

[Jim Nazium]

Originally Posted by fdeck

In fact, I suppose that you could tune the spokes on a bicycle by plucking them and listening to the note.

I never had rims that started out circular, so I end up adjusting the spokes so the wheel runs true.

It's true (pardon the pun), you can get a sense of how evenly tensioned the spokes are on a bike wheel by plucking them and listening to the notes. But you're right that rims are never perfectly round or uniformly dense, so there's always a tradeoff between roundness and even tension.

/end thread hijack

[solomon707]

Some bike mechanics do, in fact, build wheels by pitch. However, correcting rims that are out of round can result in different tensions, and hence different pitches, on opposite sides of the same wheel. I use my eyes, a truing stand, and a tensiometer.

As far as what I'd do with the info, I'm simply looking to satisfy my own curiosity and gain some more understanding of the instrument. I'm always trying to learn more about the properties of different woods, bridge metals, etc. so that I can quantify and better comprehend the differences that I hear and thus make more informed purchasing and building decisions in the future.