I've bored the hammers for the 1970 D and will be fitting them tomorrow. Perhaps this time I will solve a question that has puzzled me most of my career. In the middle and the treble, with the heads at 90° in both planes, the bore length properly adapted to the strike height and the moulding centre-line at 130mm from the hammer centre, the hammer strikes perfectly on the strike line with the key-block adjusted to roughly a middle position. In order to strike on the line in the bass and low tenor with the same 130mm shank measurement I would have either a) to move the whole keyboard and action outwards several millimetres at the bass or b) reposition the action a few millimeters forward on the key-frame. Option b is excluded because it would too much affect the geometry of the action, increasing the leverage and the touch weight. Option a would mean a bit of work on the bass key-block and the key-slip, but the keyboard front rail would not be quite parallel to the front of the key-bottom. The easiest, and probably the 'standard' way to do things is to reduce the shank measurement by the required amount and forget about adhering religiously to 130mm, and that is what I'll do unless someone comes up with an answer to the puzzle that has never occurred to me. But in order to strike on the line the heads in the bass will need to be angled slightly to the right and in the tenor slightly to the left, which is to say that the hammer rail is not drilled to the strike-points, and this is the question : did Theodore Steinway have a good scientific reason for not doing so. Did he believe that the greater the bore angle of the hammer and the angle of the strings the more the hammer-head needs to be rotated on the shank? Was he right, and if so, why does no other maker, so far as I know, do the same? JD
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