Dale, I have a Sohmer 9B in the shop. It has conventional crown which is about 1/8 in the middle. This is after restringing and being within 1/2 step of pitch. I think these are great pianos and I like their bridge agraffe system. This particular Sohmer had a very pronounced long crack running about an inch and a half or so in front of the bridge. This crack, which I have seen on several other Sohmers in virtually the same configuration, is obvious stress relief from the forces produced by the bridge operating and pulling on the board, that is, relief of shearing stresses. Usually, there is about an eighth of an inch or more of offset in height between the two parts of the board where this occurs. In the one in the shop the ribs were dowelled to the board in this area and the crack was filled with epoxy. This crack is about the only characteristic failure of the c. 6 feet Sohmers with the agraffe system I have seen, although, as I have seen perhaps, only 8 or 9 over the years, this may be a generalization on shaky grounds. The factory, apparently, was aware of this as they have attached on the botton side of the board, under the bridge, a long reinforcing strip of maple, let in and passing through the ribs. The crack occurs in front of this strip. As to the agraffe termination at the bridge, I think this works quite well and, is probably a better, but more expensive mousetrap. Perhaps the expense is not that much more than the conventional method but I would guess that it would be as the bridge requires, of course, planing, notching of a somewhat different fashion, the maple strip, notching of ribs, AND an agraffe and its installation. The ringtime of this system seems distinctly superior to my ear in comparison to the conventional method. Regards, Robin Hufford Erwinspiano@AOL.COM wrote: > Part 1.1 Type: Plain Text (text/plain) > Encoding: 7bit
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