Downbearing

Overs Pianos sec at overspianos.com.au
Mon Aug 14 14:59:31 MDT 2006


>Hi folks
>
>I'm working on a spreadsheet for calculating a few different things 
>about downbearing and just wanted to check  a few numbers with you 
>before going further then I am now.
>
>Say you have the following string situation.  Assume a bridge width of 0.
>
>Speaking length 50mm
>back length   25 mm
>Angle at the bridge 178 degrees.  (i.e. the angle created by the 
>strings deflection upwards.)
>Tension on the string lengths 160 lbs
>
>Are the following results then valid ?
>Undeflected string length total 74,98984643
>String angle from the front termination 1,333363422 degrees
>String angle from the aliquot / hitchpin  0,666636578 degrees
>String deflected Height  0,581737034 mm
>Downwards force on the bridge. 5,584676 lbs

By 178 degrees I understand that you are talking about the angle 
underneath the string segments, ie. speaking length and back length 
segments. The downbearing force you have calculated is correct, since 
178 degrees if measured from underneath translates to a 2 deflection 
of the string over the bridge.

Sin 2 degrees*160 = 5,584676

Ron O.
-- 
OVERS PIANOS - SYDNEY
    Grand Piano Manufacturers
_______________________

Web http://overspianos.com.au
mailto:ron at overspianos.com.au
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