Ric and list,<br><br>The downbearing calculations shouldn't be too terrible=
. The triangle idea is on the right track. It is called vector =
summation. The hypotenuse of the right-triangle is the string tension=
. The small side is the downbearing force (assuming small downbearing=
angle).
The angle used should be the angle between the speaking length of the strin=
g and the backscale length.<br><br>Example: Downbearing angle = 2 degrees=
, string tension = 160 pounds:<br><br>String Tension x Sin(do=
wnbearing angle) = Downbearing Force
<br>i.e. 160 x Sin(2 degrees) = 5.58 pounds (3.49% of string=
tension)<br><br>This would be real simple to add to a spreadsheet like the=
one Ron Overs posted on Jan. 21st.<br>
<br> Also, be careful with spreadsheet calculations in EXCEL. My vers=
ion uses angular units in "radians" not "degrees". =
; 180 degrees are equal to "pi" radians (pi = ~3.1416), so one =
radian = ~57.3 degrees.
The formula above in EXCEL could be "=160*sin(2/57.3)".<br><br>=
This advice has nothing to do with how much downbearing is desirable, only =
how it could be calculated.<br><br>Having just said that, it appears that i=
f the desired total downbearing is only in the ballpark of
0.5% to 1.0% of total string tension, then the average downbearing angle wo=
uld be in the range of 0.29 to 0.57 degrees. Hmm... =
<br><br>Have fun!<br><br>Best Regards,<br>Steve Fujan<br><a href="http:/=
/www.fujanproducts.com">
www.fujanproducts.com</a><br> <br><br><div><span class="gmai=
l_quote">On 2/19/06, <b class="gmail_sendername">Ric Brekne</b> <<a hr=
ef="mailto:ricbrek@broadpark.no" target="_blank" onclick="return top.=
js.OpenExtLink(window,event,this)">
ricbrek@broadpark.no</a>> wrote:</span><blockquote class="gmail_quote"=
style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.=
8ex; padding-left: 1ex;">
Please correct if this is entirely wrong... but I thought that since the<br=
>string was being measured in terms of its tension (pounds) one =
could<br>simply the problem as a like sided triangle with half t=
he pounds on<br>
each leg. Since the measurement is taken in the deflected condition...<br>y=
ou have basically the hypotenus and all angels of a right angle<br>triangle=
available to figure the amound of deflection.. pounds in this<br>case.&nbs=
p; So 160 pounds with a 2 degree deflection at the bridge y=
ields
<br><br>Sin 1 x 80 = 1.396192515 lbs downbearing,&n=
bsp; which is 1.745 % of the<br>string tension.<br><br>er... yes ??<br=
><br>RicB<br><br><br>-------------<br> > So knowing all of t=
he above, what is the equation that will calculate
<br> > an approximate string bearing load under the conditions I describ=
e?<br><br>Beats me. I use the SIN(RADIANS(degree measurement))*tension<br>p=
er unison, and add them up in my spreadsheet.<br>__________________________=
_____________________
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notech" target="_blank" onclick="return top.js.OpenExtLink(window,event=
,this)">https://www.moypiano.com/resources/#archives</a><br></blockquote><=
/div>
<br>