I have a couple of these in my service presently here in New Hampshire, and have had others in the past. These bridges probably sounded pretty good in 1925 when they were new, but as they age, they can become insanely, incredibly false. This I would attribute to the deterioration of the bearing surface of the maple just behind the agraffe where the string presses into it. The strings literally crush the surface reducing the angle of deflection of the string as it exits the back of the agraffe, and an insecure termination and the falseness is the result. I have heard these problems on a number of these agraffed sohmers, mostly the (stupid) cupid grands. So I attribute that to a flaw of the design rather than an isolated incident. Living in New England, I am in a harsh environment for pianos with dry winters and humid summers, so perhaps I see more deterioration than you do, in your more benign environment. Will Truitt -----Original Message----- From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of David Love Sent: Thursday, October 25, 2012 3:22 PM To: pianotech at ptg.org Subject: [pianotech] Bridge agraffes FYI Attached are two photos of a Sohmer Grand bridge with bridge agraffes. Very interesting in that the string bears on the top of the aggraffe hole, not on the bottom as one might expect. In order to maintain positive downbearing on the bridge, the bridge has a raised shelf behind the aggraffe such that the string runs uphill to the bridge from the hitch pin area before running downhill to the aggraffe from the short span off the front of the shelf. The slope of the string then rises as you move toward the tuning pin termination side. Sadly, I did not have my bubble gauge to try and determine the net bearing and it's definitely got me reaching for the fish oil capsules thinking about whether a measurement of the relationship between the hitch segment and the front segment would reveal the net bearing anyway. The piano sounded like caca, btw, but there were other issues. In spite of that, the tone was surprisingly focused. David Love
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