Hi all, Excellent points! Thank you. I did mention early in this thread that strings= wear grooves, flat spots, whatever, in bridge pins, and offered that as a= possible explanation for this effect. That was before it was pointed out= that the side bearing was probably a greater factor. At this point, I= wouldn't doubt that pin wear is a contributing factor to keeping strings up= pins, but probably not a primary. Pin wear, however could have an effect on= tone quality. It's been noted that most of the false beats attributable to= front bridge termination occur in octave 5 1/2 - 6. Could the fact that the= strings are shorter here, and that the width of the poor termination spot= on the pin=20is a greater percentage of the speaking length here account= for some of this? I'm leaning (sorry) toward the possibility that the= natural harmonic frequency of the flagpoling bridge pin meshes with the= harmonic structure of the strings better in this area than lower down. A= larger diameter pin, lower in the scale, would have a higher natural= frequency (being stiffer) while the string frequency is lower. You wouldn't= get a match lower down like you would (might) in 5 1/2 - 6. It might be= frequency coupled. What do you think? =20 I have also begun to suspect that the grooves in bridge tops are nearly= inconsequential in this process. I see them as merely a result of the= bridge expanding and crushing wood. In another post, I asked if anyone taps= strings down at the back pin. If they don't, how else does the bridge get= string grooves all the way across the top unless it's the result of this= expansion and crush?=20 Wouldn't you know it. I went and changed the thread title and everyone came= back. Murphy, is that you? Regards, Ron Nossaman > >I find this discussion very interesting. One thing that was not mentioned >though is the fact that the bridge pins are softer material than the >strings. When I remove these I usually can see indentations (is that >English?). They actually are grooved. No wonder string want to stay up >there. Since all the force is usually applied upward, that groove will have >a tendency to be above the bridge plane. IMHO, that might be why when >rebuilding it is necessary to replace these pins. The notching will help >too, but I'm not so sure the sanding of the bridge would make such an >improvement.=20 > >Marcel Carey, RPT > > > Ron Nossaman
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