Spring behavior

[Jon Page]

I'm looking for the quick convenience of a digital numerical output. This 
would be in the rehlm of actually relieving
the SW of the wippen which is about 20g. I'm also looking to graduate the 
tension for repetition lever tension; that
has to be a significant number; has anyone measured the weight of the 
hammer at the wippen contact point?
I'm sure they have but not relinquished their findings.  Just what is the 
tension required to lift the bass hammer
from check compare to a treble hammer.  Inquiring minds want to 
know.  Friction is a factor, but what is the spread.

The range for this kind of strain gage is in the $600 region with computer 
interface option a little more. That would
be nice for push-button Touch Weight data entry but for non-production 
shops such as mine; that option is pie-in-the-sky.

Time on my hands and money to burn...

Jon Page

At 05:31 PM 10/25/2002 -0500, you wrote:

>>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
>
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