> One of the things I have >wondered about is bridge pin row spacing (am I saying that right? - the >distance from the front bridge pins to the back bridge pins) and how >manufacturers decided on that spacing. I guess that's right, or near enough for communication. I don't know if there is "official" nomenclature, but even if we have to make it up as we go along, the ideas get across. In any case, as you probably suspected, there's more aggravation to be had on this subject. The farther apart the row spacing, the less precision required in lateral pin placement to achieve a target stagger angle. The closer the spacing, the greater the required precision. Meanwhile, if I was designing the bridge, I'd want the pins in far enough from the edges for good support, yet close enough to the edges to minimize the amount of wood I'd have to remove to cut the notches. No sense making life harder than it has to be. That means that as the bridge angle relative to the strings narrows, I'd increase the row spacing. It takes a little more time and thought in planning and layout, but anything that cuts down (sorry) notching labor is definitely my friend. I make nice clean notches, mind you, it's just that I don't much enjoy doing it. Maintaining the row spacing through the whole piano works fine too, but you spend more time hunkered over a chisel producing it. Someday, a power notcher. Of course, if you are working with a re-capped bridge on a soundboard that isn't being replaced, you can't mess around too much with row spacing unless you want to rescale with the newly resulting speaking lengths. Not that it's a problem, but it bears consideration. If by the happiest circumstance, you're making your own bridges, you can correct the log progression deviations across the treble breaks, smooth the transition across the bass/tenor break, and generally build about anything the plate will let you get in the piano. That's when it gets fun. Ron N
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