removable strain gauge to measure strain in band

How do you make a strain gauge device that measures the strain (change in length) of a metal band by clamping the gauge device onto the metal
band. The gauge would be an analog bridge strain gauge that would have to have pads that allow them to be clamped on the metal band, but the material that the gauge device was made of would have to have little effect on the total resistance to elongation of the band, since the band strain vs. force is what is being measured.
I know I could glue a strain gauge on the band itself to do the measurement, but I want to be able to mount and unmount the strain gauge on different bands.
The actual thing I am measuring is the tension in a bandsaw blade. I found I could buy a mechanical strain gauge to do the measurement, but find that I can buy a used strain gauge meter for much less and if I can make a gauge, I will have a strain gauge meter for use in other applications. Also, I believe it could potentially be more accurate also.
sci.engr.mech
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A removable strain sensor is very easy to make.
A simple "C" shape made of light gauge metal, for your application maybe .75" radius. The strain gauge is placed midway between the two ends. The tips of the "C" could be magnets, or sharp points, held in place with clamps, or even storng rubber bands.
http://www.princeton.edu/~humcomp/sophlab/m&mgl_30.htm
Dave
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wrote:

You could cement a rosette or similar strain gage to a thin aluminum strip, and clamp the two ends to the steel bandsaw blade, making it as tight as possible, I suppose. It's not likely to give great results I don't think: still, if you reclamped and tested a half dozen times, the differences you see might wash out to some extent.
Brian Whatcott Altus OK
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Sounds like you're attempting to make a clamp on strain gage based extensometer.
Knife blade clamp on extensometers are pretty standard in the material testing world.
I'd guess that clamp on extensometers exist for thin materials as well.
Check out Tinius Olsen, MTS, Satec, Instron for an idea of what exists.
Depending on how accurately you want to measure the tension, I'm sure there are easier & cheaper ways.
cheers Bob
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