A fellow technician has a client here in Boston with an old Chickering concert grand that is a real string-breaker in the bass, typically right in front of the tuning pin. It's S/N 5014, marked on the strut and on other case parts (1840?!?! Or 1905, if 105014?), eight foot something, with "Scale 131" cast into the plate, and a small "D" in the plate at the tail. It has 8 monochords, 11 bichords, and 9 wound trichords on a transition bridge connected to the bass bridge with a slat of wood that doesn't touch the soundboard. The action brackets are wood; it seems you take off each rail to get the top action off. The hammers are narrow, around 8-9 mm, and are in excellent shape; they appear newer than their shanks. Brass flanges with a mysterious hole between CP and drop screw. Plastic keytops that the sharps bury into. Nice red mahogany, as seen on the fallboard; the rest is alligatored and dark. Some cracks in the soundboard, but all the ribs are tight. The bridges are screwed on from below. A few cracks at the base of bridge pins in the bass, but they're pretty far apart. 3/0 tuning pins are on the loose side, but no visible pinblock problems (screws go up into it from the action cavity, as well as down from the top). The problem with bass string breakage seems to be twofold: a humidity problem in the basement (rust on the tuning pins) and a severe deflection angle on the 8 monochords. It's perhaps 5" from pin to agraffe, but the pin is a good 1 1/4" higher than the speaking string height. There's a 1" wide plate mound in this section that deflects the string at maybe 40 degrees, roughly. The understring felt is worn through, but I doubt that alone is the problem (right?). Current thoughts are to experiment with grinding down that plate mound to see what improvement in deflection angle is possible. He'd like to replace all the bass strings. Any suggestions? Perhaps replacing wound tri's with plain bichords? --Cy-- http://shusterpiano.com
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