Del Wrote: << Keep in mind that even with this restriction it is still possible to overload certain plate members. Consider that many piano scales, especially small ones, really drop tension through the low tenor. It is common re-scaling practice to increase this. Now consider that this same piano might have had fairly low tensions at the upper bass bi-chords -- also not an uncommon scenario. So those get raised as well. We find that we can keep approximately the same overall tension on the scale because the mid-tenor tri-chord tensions were quite high. The problem, of course, is that the bass/tenor brace now has quite a lot more stress on it than it had originally. It's true that the tenor/treble brace is more lightly loaded now, but that doesn't help the bass/tenor brace at all. It is entirely possible to increase the load on the bass/tenor brace by 20% or 30% without increasing the overall scale tension at all. I am obviously a firm believer in the practice of re-scaling older pianos. I would just urge a bit of caution along the way. Del >> You read my mind! That was my next question. I've been able to lower my original attempt numbers. I currently have a scale that is only 375 lbs higher then what I started with. And I strongly suspect that the instrument does not have its original bass strings (the unwrapped ends by the agraffes are all 1 1/4" long) so maybe this piano had a higher tension when it was built. But I WAS wondering about the redistribution of tension. Am I correct in thinking that even if a hitch pin for a bass string is immediately behind one for a treble string, changing the tension on one won't have an effect on the other (because the tension is inline with the string)? Gordon Large, RPT Maine
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