Terry,
My understanding of the reasoning for the shape of the "bottom"
(horizontal) shape of the flange is that it forms more of a "three-pointed"
surface contact, providing more stability that a truly flat contact area.
Your add-on looks crucial, (and elegant) and the picture makes me wonder if
the system wouldn't benefit from a papering of the surface of the main rail
where the "bottom" of the butt flange makes contact It looks as if there is
perhaps too much room there, and .010 or so of shim might give a more solid
base at time of string/hammer contact. Know what I mean?
Guy
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