> I accept Ron Nossaman's analysis: bridge expansion and contraction > pushing the string up and down the bridge pin are the main factors in bridge > pin wear. Considerably more friction (between pin and string) is involved in > this motion than in strings being drawn through/past the pins in tuning. I > also accept the notion that there is simply too much friction at the bridge > for wire to slip past both pins and bridge top except when there is a very > large change in pitch (in the 100 cent range), based on experience, > experimentation, and the experiments and analysis of others. Hi Fred, Consider that if the string can be moved up and down the pin by cap dimensional changes, the friction between string and pin is overcome in small increments to allow it. As the string moves up or down the pin, the differing segment tensions will take advantage of the momentary friction respite, and the string will also render across the bridge somewhat. This happens at odd intervals as long as the cap thickness is changing, which is most of the time. Nothing ever stands still as long as there are changes in temperature and humidity, so nothing ever quite reaches equilibrium. Ron N
This PTG archive page provided courtesy of Moy Piano Service, LLC