Spring behavior

[Ron Nossaman]

>I plan on purchasing a Strain Gage soon to actually measure the difference 
>and then be able to calibrate the
>tension out of the piano. This pre-tensioning is proposed for wippen 
>assist spring tension as well.  I hope
>to reduce the time needed to afine-tune the tension once installed and 
>gain the best spring curvature with visual
>inspection.

Hi Jon,
A strain gage is probably overkill. You can set up a lever arm with a 
sliding weight and deflection pointer that will most likely tell you all 
you need to know with stuff you have lying around in the shop already. 
Calibrate it with your little electronic scale (which is already a mounted 
and calibrated strain gage). Just a thought.

Ron N