Key Ratio

[David M. Porritt]

Richard:

Remember if you are measuring these lengths, the front is from the TOP of
the key to the bottom of the key at the balance pin.  The back is measured
from the bottom of the key at the balance pin to the top of the capstan.
That is where the forces apply.

dave

*********** REPLY SEPARATOR  ***********

On 10/3/00 at 10:22 PM Richard Brekne wrote:

>In my continuing exploration of Stanwoods stuff I ran into an interesting
>little dicrepency on my Duysen Grand action today. I have been scratching
>my head a bit about the apparently high Key Ratio figure obtained by the
>Standwood method. This hovered around .60 grams on all samples. Haveing
>rechecked a few times without finding any other result I decided to
measure
>the distance between the center of the balance hole, and the capstan
center
>on the one end and the end of the key on the other end.
>
>To my suprise the measurements in lenghts resulted in a Key Ratio of 5.6.
>Course I rechecked this several times to see if I could get the ratios to
>coincide better but ended up with no real change.
>
>The distance from the center of the capstan to the center of the Balance
>pin hole was 12.1  cm and the distance from the center of the Balance pin
>hole to the key front was 21.5cm. The only thing I can think to explain
>this is that Key ratio figured by lengths has to be taken from about 1 cm
>back from the front of the key. Is this how its figured then ??
>
>--
>Richard Brekne
>RPT, N.P.T.F.
>Bergen, Norway




David M. Porritt
dporritt@swbell.net
Meadows School of the Arts
Southern Methodist University
Dallas, TX 75275