John Hartman wrote: > > Richard Brekne wrote: > > John Hartman wrote: > > >>45*980gm/sec^2 - 10*908gm/sec^2 > > Sorry, > > It should be: > > 45gm*980cm/sec^2 - 10gm*980cm/sec^2 > > Which is the force (balance weight times gravity) needed to put the > action into equilibrium (assuming no friction as usual). > > John Hartman RPT > Grin... figured as much... tho its best to be sure. Thanks John. Hadnt really thought of BW in these terms until the other day when you brought up that perspective. One question tho... I suppose it would be easy to think that the above implies that any movement of the key means accelerating the key mass front of the balance rail pin faster then 980cm/sec^2... which I dont think is what we mean. And that I think is also central to Freds question about how assists (of any sort) change overall MOI and how the finger senses that. In all this we need to remember that whatever the MOI contribution of the key mass forward of the balance rail pin is, it aids (in gradual decreasing degree) the finger until that mass exceeds an accelleration of 9.8m/sec^2. The key mass at the finger will reach that accelleration rate much sooner then the key mass at the midpoint between the balance rail pin and key front... which of course leads into that whole discussion about lead placement and MOI. We are left with two considerations then... how much counterbalancing in general AND how much key inertia from key front mass we are to employ. Stephen Birketts contribution a while back is well worth a re-read for anyone following this thread, and I think goes a long ways to answering Freds question. Cheers RicB
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