[pianotech] Bridge Pin Drilling Angle

pianoguru at cox.net pianoguru at cox.net
Thu Dec 25 19:56:05 PST 2008


Hi Paul,

You are absolutely correct.  The more information we can collect from as many sources as we possible can, the better conclusions we can draw,  My point is that once upon a time the "consensus" of "scientists" was that the Earth is flat.  I welcome as much information and opinion as I can find, but my judgement, in the end, will be guided by my own best judgement, regardless of statistical "consensus."


---- PAULREVENKOJONES at aol.com wrote: 
>I'm curious about the compound angle. Why did you do that? What were you trying to achieve?

If the speaking length is parallel to the tail length, and the side bearing between the front and back bridge pins is ... say 8⁰ ... then the pressure from the string applied to the bridge pins bisects that angle at 4⁰.  Would it not make sense to angle the pin to directly oppose the pressure applied from the string?  The function of the bridge pin is to clamp the string to the bridge.  This suggests to me that a 4⁰ angle to the front, for the front pin, and the same to the back, for the back pin, would be optimal for clamping the string to the bridge.  

The next question is:"Is there enough difference to really make a difference between a simple angle and a compound angle?"  At this point in time I would say, "No, it is not enough difference to matter."

Another issue to consider is that,at some point along the treble bridge,the front bridge pins will intersect with the back bridge pins of the neighboring note.  Adjustment needs to be made in the distance between the front and back pins to avoid this conflict.  A compound angle complicates the calculation to avoid this conflict.  If there is not real advantage to be gained by the compound angle, why bother?

Frank Emerson



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