On Mon, 13 Dec 1999 11:45:05 -0500 "David C. Stanwood" <Stanwood@tiac.net> writes: > Fri, 10 Dec 1999 "Richard Moody" <remoody@easnet.net> Wrote: > > >Also I wonder why a simple differnce between DW and UW can't be > used. At > >least for friction reducing attempts. I think it (the difference) > is > >divided by two because levers are involved, but at the keyboard the > first > >"reading" is the actual difference. Why have to mentally divide > that by > >two and remember that also? So would it be wrong to say? "since FW > of 10 > >is acceptible, then a diff of DW and UW of 20 is acceptable but > getting up > >there." > > Dear Richard, > > I'll start a new subject on this because your focusing on a point > that is > important to understand in itself. > > Why not make an action that has no friction! Ball bearing knuckles, > ball > bearings in the hammer and wip centers, ball bearing heel cushion, > and ball > bearing key pivots and guides. (Of course these would have to be > dry ball > bearings so as not to cause any extra drag) > > Now we measure down weight and it turns out to be 35.001 grams and > the up > weight is 34.999 grams. But since we normally measure up weight and > down > weight to the nearest gram these figures both round out to 35 grams. > So > with no friction, Up Weight and Down Weight are the same. > > Now let's spray mist the ball bearings with a mixture of 80% water > and 20% > alcohol. > get that water right into those bearing with a liberal soaking! Let > stand > for one full day do allow for full rust development. > > Now remeasure Down Weight and we find it has increased by 13 grams. > It was > 35 grams, now it's 48 grams. 13 grams is the additional weight > needed to > overcome the friction in the rusty bearings. That's why it's called > Friction Weight. Now we measure Up Weight and we find that it has > decreased by 13 grams as a result of the friction in the rusty > bearings and > now measures 22 grams. > > So this 13 grams is called "Friction Weight" and in the real world > we find > it as: > (D-U)/2. > > As you can see in this case, referring to friction as 26 grams > doesn't > really tell you the effect of friction on either Up or Down Weight > until > you divide by two. > > Also, the 35 grams in this case, is referred to as "Balance Weight" > and is > found as: (D-U)/2 > > In defense of these terms I have to take exception with the comments > by > Mark Abbott Stern in his December 1999 Journal Article "Touchweight > & > Friction" > > He his introduction he states: > > "The hardest part will be giving up the belief in a widely accepted > statement: "One half the difference between down weight and up > weight is > the friction of that note." Not entirely true. Repeat --- not true. > Friction is certainly a part of that value, but there's more to it; > there > is a portion that cannot be reduced by all the lubricants in the > world." > > He seems to imply that, by using all the lubricants in the world, we > have > eliminated friction and since there is still a difference between up > and > down weight, it must be from some other cause. He goes on to make > the case > that force vectors are the cause of it. > > My take on this is that if we reduce friction as much as we can (and > this > is not necessarily desirable) there is still plenty enough friction > leftover to cause a difference between up weight and down weight. > > If we TRULY eliminated friction (Ball bearings) ****Sorry, but even ball bearings have "some" friction. Idea as long as this has been brought up. What about magnetically opposed identical poles facing each other ( north pole to north pole which would repel rather than attract - and with a lot less friction than the worlds most carefully machined ball bearing. John Fortiner Billings, MT. there would be one > weight > placed on the front of the key that would cause it to become > balanced. The > slightest amount added or subtracted to that weight would cause the > key to > move down or up irregardless of the force vectors within the action. > > David Stanwood > > ___________________________________________________________________ Why pay more to get Web access? Try Juno for FREE -- then it's just $9.95/month if you act NOW! Get your free software today: http://dl.www.juno.com/dynoget/tagj.
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