Richard Brekne commented: >Thirdly.... aside from a basic rule of thumbs as to what the general dynamics >affect of key lead amounts and placement, how does this detract from the >equation based static balance approach to action balancing ?. Static balancing >is easy, and can yeild various sorts of eveness in as much as FW can be >accomplished in several ways. If we simply know some general consequences for >various configurations of key leading... those can be made to conform to just >about any given FW specification easily enough... or what ? Balancing inertial properties across a keyboard is not much more difficult to accomplish than static balancing using touchweights. You have two independent parameters to adjust in the key instead of one...the only practical limitation is that you cannot use pre-defined lead weights and simply stick them in the key where the desired balance is obtained. You have to be able to adjust both the mass of the lead and its location separately. and Bill Ballard commented: >Stephen Birkett answered quite neatly that the same counterbalancing >lead moved from under the finger at the front towards the key's >fulcrum, yields more acceleration for the same size blow. Maybe he >can answer this next question: if two keys of identical static >balancing yet different placement and masses of lead do yield >different accelerations for the same blow, what does that graph look >like? >Anyone else willing to send Stephen a box of chocolate chip cookies >for a picture of this? I am. Well...actually oatmeal chocolate chip cookies are my preference.... I've inserted a few extra slides into the set previously referred to here <http://real.uwaterloo.ca/~sbirkett/inertia.pdf> to cover the general case and how static and dynamic balancing can be done simultaneously. It isn't really all that mysterious. John's nice little diagrams with the hanging thingie on the string remind me of another nice analogy of dribbling the basketball. Stephen -- Dr Stephen Birkett Associate Professor Department of Systems Design Engineering University of Waterloo Waterloo, Ontario Canada N2L 3G1 Davis Building Room 2617 tel: 519-888-4567 Ext. 3792 PianoTech Lab Ext. 7115 mailto: sbirkett[at]real.uwaterloo.ca http://real.uwaterloo.ca/~sbirkett
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