>>>> Once again I will raise the dreaded moment of inertia to answer this one. There is a difference. The static (touchweight) is based on the first moment of the key about the pivot and varies as the distance between lead mass and pivot. The dynamic (feel) of the key is based on the second moment (moment of inertia) and varies as the square of the distance between lead mass and pivot. Thus when you move the leads to the middle of the key and *slightly* increase to balance the touchweight you reduce the moment of inertia significantly (even though the leads are a bit heavier)...hence the key feels different. Another analogy...golfclubs are (or used to be) sold in sets which were statically matched (i.e. the first moments about the grip were the same)...called `swing weight', which is identical to D.Stanwood's strike weight! Recently some manufacturers started making sets that are dynamically mateched (i.e. the second moments are the same). You can't match both first and second moments, because one varies in proportion to distance whereas the second varies as the square of the distance. Stephen Birkett (Fortepianos)>>> Excellent analogy! I have removed leads and rewieghted. After the leads are removed I use a Forstner bit to make the hole clean (they are usually tapered). Next I make appropriate size plugs to go in these holes. Now I can rewieght without fear of my new holes that I will drill running into the old holes. Michael Wathen University of Bob
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