Concert Grand Reproducers
By John Grant
Hello Michael (and List),
Regarding your recent inquiry regarding reproducing mechanisms in concert grand pianos, I can offer one example, a Welte Licensee action in a 9' Steiff piano. I restored this piano (along with several partners who were responsible for various aspects of the restoration) about 12 years ago. Although my notes about this piano are somewhat sketchy, I can offer some approximate details and research specific information if there is further interest. The piano is the property of a Baltimore retirement home, having been donated to them in the mid 30's according to an attached brass plaque. The piano itself, as I recall, is from the mid 20's, and seems to have been Steiff's stock design of the time. That is to say, the structural design of the piano has the splayed timbering normally associated with non-reproducing piano case styles. In this instance, approximately two feet of the main longitudinal beam had been none-too-subtlely removed to allow space to mount the box pump.
Upon tear-down and removal of the plate, we discovered that one of the long cross struts on the top of the plate had a sizable crack in its root where it joined the plane of the rest of the plate. The plate, sitting in the shell with no tension applied to the strings, could be "rocked" about 3/4". Apparently, removal of the beam had allowed the string tension on the plate to slightly warp the entire case. What initially looked like a serious problem was solved by adding some structural reinforcement in the "toe" of the case, and by drilling through the back of the plate into the thickness of the strut, tapping, and installing a case-hardened cap screw. This was to keep the strut from moving laterally when tension was reapplied to the plate, as the tension itself acts in a direction to keep the crack closed. The repair is invisible from the top of the piano and
will only be apparent to the technician who next removes the plate.
-John Grant
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(Message sent Wed 15 May 1996, 03:52:05 GMT, from time zone GMT-0700.) |
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