> <G> I knew you were going to ask that. Two good questions for which I > don't have answers. So, in the meantime I guess I'd better use 10 deg. > and 20 deg. until I can come up with some answers. > > Phil F Just trying to hold up my end - even if I'm late getting to it. <G> I've thought a lot about this through the years, and I think you're right that we need to know what the tolerances are and what we can do to get a more equitable split among the available factors. But I wonder what it is exactly that we think we want? How easily, for instance, do we want a string to render through a bridge? How low a friction level can we tolerate before we get weird pitch WOWs in the attack? Or would we? We know that pounding too hard while tuning can leave front section tensions too high, and speaking pitch will creep up as the string renders across the V bar or agraffe. How does that work with bridges, and how can we control it? I don't have answers. I do think that, although there are surely better ways, the present system generally works very well as a cheap, easily built and tolerant string termination system. The only major drawback I see is that the cap material isn't dimensionally stable, and the stresses resulting from that exceed the compressive resistance of the material. If the cap didn't change dimension, the notch edge wouldn't crush below the string, and the pin likely wouldn't get loose (or not AS loose), and the weird tonal anomalies that send the tuners digging in their cases for brass punches and little bitty hammers wouldn't be in every piano we tune. A decent capping material should take care of a large percentage of our bridge maintenance problems, leaving us more time to fuss with duplexes and such. The system might just not be all that broke, and that may be all the research needed to adequately fix it. I still like the notion of bridge agraffes though. Ron N
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