On most pianos , especially quality grand pianos, the plate is suspended above the soundboard on "acoustic" dowels. The theory is that by being suspended in this way, the plate does not hinder the movement of the soundboard, although the movement at this location is very limited because this is directly above the rim where the soundboard is glued. Since the dowels are located under the plate at the perimeter of the soundboard, it is difficult to set their height. Here is how I accomplish this feat easily and accurately. First I drill the holes in the rim that will receive the dowels. The I insert a "dummy" dowel (no it doesn't talk) with a hole drilled in the center. A smaller dowel is inserted in the hole. It is dimensioned so that the inner dowel is tight, but still movable in the outer dowel. The center dowels are left high. The the plate is set in the piano, resting on the pinblock and the rear plate suspension bolt. The weight of the plate pushed the center dowel into the outer dowel, and stops at the proper height. The "dummy dowels are numbered and removed. Their length is measured with a caliper, and recorded. Then I simply cut and sand the real dowels to the same length. Now all I need to do is insert the support dowels in the holes with glue, and they will fit perfectly. On this piano there are 24 dowels.
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