I beleive that this model of Currier had what they called a "stratophonic string panel" or some similar name. As you have described, there is a face plate of steel over the cast iron plate. These would sometimes come loose from the plate and push forward against the strings. The only remedy is to loosen the tension on the strings, drill through the face plate, drill and tap holes in the plate. and bolt the panel back to the plate. If I recall correctly, 6-8 bolts (1/4" dia) would suffice. After the repair, the piano would be a sufficient instrument for the normal home application. Hope this helps. Kent Webb
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