>Ron, >The bridge pin angle seems to be about 25 degrees. I take it from your >response that you've seen other pianos with angles this much or more >that don't have cracking problems. Since I'm as mortal as can be expected under the circumstances, I haven't seen all possible configurations of anything, much less everything. With that in mind, the bridge failures I've seen through the years have seemed to me to be more related to the grain angle relative to the bridge root, and/or the degree of quartersawnedness of the cap, than to the excessive draft angle of the bridge pin. If "quartersawdness" proves on examination not to be a real word, I can only take the "look and feel" plea in defense. My grasp of the language does occasionally fail me. A less than adequate angle does, however, present a rather dramatic set of tonal problems when the front bearing angle is inadequate. >This is also tied in with where the >bridge pins are located relative to each other. If the back holes are >directly behind the front holes with a 25 degree pin angle then you'll have >more load on the pins than if the holes are slightly offset from one >another with the 25 degree angle. On this piano the back bridge pin >holes appear to be directly behind (in line) with the front bridge pin >holes. > >Phil Well now, this is another thing altogether. The relationship of the pin angle to the stagger angle isn't a direct correlation. Both the pin angle and the stagger angle are individually and rather easily determinable before a hole is drilled in the bridge top. One isn't in any way determined by the other unless the bridge architect is operating by rumor, innuendo, dumb luck, what he thought he overheard in the bar at the Cleveland convention, or horoscope - status quo to the contrary. It's really not random chance in practice, and ain't that hard to figger. Ron N
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