Key Ratio?

[Richard Brekne]

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Dave Nereson wrote:

> So... I ask you...  why we are supposed to measure down to the balance
>
> rail, and up to the capstan and at the same time  not take into
> consideration the horizontal deflection of their angles before
> figuring
> their ratio ?
>
> RicB
> I don’t know. But in this month’s Journal, on page 36, that’s where it
> shows to measure. ;)
> -David Nereson, RPT, Denver
>

I think if you read the text of the article you will find it quite
purposely avoids defining the << correct >> method of measuring the arms
of the levers.

In the second paragraph two key sentences


     "...the Stanwood Strike Weight Ratio (R) can be expressed as
     the product of the appropriate individual leverage ratios of
     the  three levers of the action:  the key stick, the wippen,
     and the  hammershank"

and

     "This value for the overall ratio of the action can be arrived
     at by measuring the appropriate lengths of the arms of each of
     these levers in much  the same fashion as the overall action
     ratio traditionally has been calculated."

further a footnote which states the following.

     "It must be noted that there are several conventions for
     measuring hammer shank ratio and it has been long debated
     which of these is most useful. Regardless of which convention
     is used at any given time, it is important to agree on which
     set of parameters are being discussed so as to assure a common
     ground for meaningful discussion."

--
Richard Brekne
RPT, N.P.T.F.
UiB, Bergen, Norway
mailto:rbrekne@broadpark.no
http://home.broadpark.no/~rbrekne/ricmain.html
http://www.hf.uib.no/grieg/personer/cv_RB.html


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