David writes: << I'd much rather watch the video of you leveling the Lowell gauge to the top of that thar bridge. One of those "direct to video" releases, I suppose. Fact is, I can't visualize how the gauge would tell you much of anything with that configuration. Unless I'm mistaken (or mis-visualizing), there's no direct relationship between the front string termination (the agraffe) and the distal side of the bridge. Actually, I wasn't sure, from your description, what, if any, bridge-segment measurement you did take. >> If you zero the gauge on the speaking length, and then, with the legs quite close together, place the gauge on the string between the front and rear bridge pins, it will tell you what the bridge's contribution to the deviation between agraffe and hitch pin is. When I find that the string goes up from the proximal bridge pin to the distal one, I know that the string is relying on the proximal bridge pin to hold it to the bridge, which usually gives poor termination. I also suspect that the bridge has rolled forward,(toward the V-bar). This, I call bad. If the bridge segment lies directly in the same plane as the speaking length, and then drops down to the hitch pin, I don't feel the need to correct anything. If the string angles downward as it crosses the bridge, and then measures the same angle between bridge and hitch pin as the speaking length, I know that there is downward pressure there, whereas simply comparing the speaking length to the back string angles might have indicated that there is no downbearing. I use the tool to visualize the string as three segments. How they relate to each other gives me my picture of downward force or lack thereof in the bearing. I am not saying that everyone will see board loading from this perspective, but it has become one of my parameters in making decisions when I change the bearing. Regards, Ed Foote RPT http://www.uk-piano.org/edfoote/index.html www.uk-piano.org/edfoote/well_tempered_piano.html
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