Hi! First of all, thanks for taking the time to answer my post. I didnt think I would come online before monday, but I did :) I was expecting to have to straighten some things out, since english isnt my mother tounge, so here are some more questions and some explainations. > More information would be helpful in diagnosing your dilemma > but I suspect there is an error perhaps in the way you are measuring bearing. > How was that done? We usually use those simple tools sold by all pianotech companies that you put over the bridge, measuring the angle of the string right over the bridge. So we could not have misstaken zero downbearing for positive downbearing. When the strings where off we used a strong thread through the agraffes and down over the bridge. That the downbearing decreases noticable is something we all have noticed at school. It always happends. Sometimes little, sometimes alot as in this case. Thats why I wanted to discuss it. So, it didnt have zero downbearing anywhere. Thats why we can exclude the idea of the strings actually lifting the soundboard upwards when the strings were there. > You did not mention crown. Did you check it before and then after it was > unstrung with a string across the bottom of the board. I've been fooled by We only measured the crown after the strings were removed. It had some crown, but it wasnt much (I really dont know how to define much crown though) > > Then I formed a second theory about the dissapearing > > downbearing. Could it be that the strings actually > > compresses the cast iron and the cast iron compresses the > > whole soundboard giving it a part of its crown in that way? > > >>>>>>>>>>Are you using crown and bearing as innerchangeable concepts? What I meant was that when the strings are in place, with that incredible tension the whole cast iron was compressed from the pins to the bottom bolts where its hold firmly together with the frame all around the pianos rim. This is just a theory, but perhaps the crown of the soundboard then increases as the whole piano is clamped together of the stringtension, giving the soundboard a slightly bigger crown of the soundboard. What do you think about that? I cant find any other solution to why the downbearing decreases alot when you remove the strings. > >>>I usually don't because if it has ehough when the strings come off I can > reuse the board and if not it gets a new one. I honestly put more stock in > the way the piano sounds before it's torn down than any physical > measurements. For example I've had some amazing sounds come from boards with > no crown and minor amounts of bearing so what do I care what the measurements > are. I've also had fully crowned 9 ft kawai piano les than ten years old with > 10 mm of crown strung and no bearing. I hated the sound. Both in this case > were verifiable with measurements. > Hope this helps Yeah, I totally agree. If it sounds good, why bother. :) Thanks, Daniel Lindholm
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