---------------------- multipart/alternative attachment Ed... Here is a little experiment for you as long as you are looking in this direction. Obviously you seem familiar with Stanwoods Front Weight quantity. So you know also that you can achieve same front weight by useing more lead closer to the center of the key. Ok... say you need a key with 40 grams of front weight. Take a 25 gram weight and place it on the (unleaded) key so that your Front weight reads 40 grams. Now mark that spot. Now take 2 lead weights that weigh 12.5 grams each and place them on opposite sides of your mark equal distances from it. Try several equal distances. Then try 5 weights that are 5 grams each... on exactly on the spot.. the other 4 as above... equal distance from / opposite sides of your mark. Now before you run and start figureing point mass for each lead.... remember the key, even an unleaded one, has mass of its own. Figureing the key inertia this way is going to require you to take many point measurements to get a good representation. I think you will find that we need a more direct and quick way of measuring key inertia, and that we still dont really know how to equate that with touchweighting beyond very general purpose. Intuitively tho.... we know that more mass in general leads to higher inertia. On the other hand... for same FW... lower inertia is achieved by concentrating greater mass towards the center of the key. So you can without further ado use these two facts to in general decide relative key inertia levels. Yet we still havent really quantified just how much key inertia is desireable for any given action ratio, SW, etc. Just some food for thought... tho no doubt you've already thunk up some of this :) Cheers RicB Ed Sutton wrote: > Vince- Wow! Easy to calculate. (I thought it was one of those > progressions to the infinitesimal formulas.) This gets exactly to the > unanswered question when setting front weights, i.e. one in front or > two in the back? etc. In fact it should be fairly easy to make a > reference chart in, say half inch increments. I'm rebuilding an action > after Xmas, and I just might knock out the old weights, plug the holes > and go for broke. Thanks very much! This is a real Xmas present! Ed > Sutton -- Richard Brekne RPT, N.P.T.F. UiB, Bergen, Norway mailto:rbrekne@broadpark.no http://home.broadpark.no/~rbrekne/ricmain.html http://www.hf.uib.no/grieg/personer/cv_RB.html ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/caut.php/attachments/35/98/9b/c9/attachment.htm ---------------------- multipart/alternative attachment--
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