I'll give this a shot: Formula for action leverage (Baldassin/Robinson) : (Blow Distance - Let-off / Key Dip - After Touch) = (Key Out / Key In) (Wippen Out / Wippen In) (Shank Out / Shank In) In English: (BD minus L/O divided by KD minus AT) = (KO divided by KI) times . . . cp contact point (my abbrev.) All measurements are taken with key at half dip. Key Out Bottom of keystick, center of balance rail hole to cp capstan/wippen Key In Bottom of keystick front to center of balance rail hole Wippen Out Center pin to knuckle/wippen cp Wippen in Capstan/wippen cp to center pin Shank Out Center pin to strike point Shank In Center pin to knuckle/wippen cp (just forwards of core) I haven't gotten to play with this yet, it seems to me to be a lot of measurements to take with great precision for the equation to balance. I would think it is helpful with decisions on knuckle radius, capstan placement and action spread. Or for just chosing a Blow Distance and Key Dip. TINTM This is new to me :-) But I will investigate. At 02:53 PM 10/29/98 -0500, you wrote: >Should someone else have the formula (and a scanner) I would be most >appreciative of receiving this. I wasn't able to attend Providence but hope >to show my funny face in Kansas City. Action spread is usually around 4 >13/32" right? David Stanwood has mentioned in previous classes that >generally the spread isn't as big an issue when calculating overall >leverage....I guess the next question would follow (maybe Jon and others can >answer): If the spread is greater, say 4 1/2", exactly how will this affect >the Strike Weight Ratio?...or would the differences exist...still >thinking....in whip ratio?...Trying to sort this out. Can we make a >significant difference in the leveraged system as a whole by altering the >spread? (There, got that out of my system). Action spread is another area which I have misgivings. I do know that by increasing the spread, the capstan moves away from the fulcrum the same as the knuckle does, so in essence maybe one cancels the other. I'm not sure. Except I know the touch weight does not significantly change. I have utilized the spread to better regulate actions, ei: dorp screw too high, L/O button too high: expand the spread and these will lower. I would say that 4.5" is max on spread. The parts are not designed for alignment beyond that. This is where the "formula" would come in handy. > >Thanks for reading, > >Blubbering hammer head >Dave Swartz, RPT >dms2000@majesticpiano.com > >At 01:35 PM 10/29/98 -0500, you wrote: >>In cleaning out the pile of papers on my desk I found another >>pile underneath it. Amongst them was the hand-out from the >>Providence Convention about "Action Geometry: Truth And >>Consequences" by Rick Baldassin & Chris Robinson. >> >>Previously I mentioned, that with the key half depressed >>the knuckle/wippen contact point fell on the action spread line; >>as recalled to the best of my knowledge from their class. >>I obviously did not recall the information correctly. The lines >>they drew on the action parts (pictured indivually, not on the stack) >>are between the center pins and their respective contact points, >>but no mention at all about proximity of said contact point to action >>spread line. Which Don M. pointed out on mIRC one night that the >>contact point_is_ below the spread line at halftime. I tested and >>found that to be true, I could not find the hand-out and refresh my >>memory on the class, but now I have. It is an interesting forumla >>but unfortunately I do not have a scanner. >> >>I know you all were waiting for me to find it and clear that up. >> >> >> >> >> >> >> >>Jon Page >>Harwich Port, Cape Cod, Mass. (jpage@capecod.net) >>~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> > > Jon Page Harwich Port, Cape Cod, Mass. (jpage@capecod.net) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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