Greetings: It's only logical that weight and distance ratios are related. You can't change the weight ratio without creating the need to alter regulation specs. While problem actions we're talking about that have excess lead have, by definition, a mismatch between ratio and hammer or strike weights, they also generally regulate with too shallow key dip (<10 mm), at least by modern standards. Changing the capstan or knuckle position to improve the ratio to strike weight relationship will entail increasing the dip but that's usually a good thing, or at least a perfectly acceptable thing. If you want the action to regulate by older standards with shallower key dip you will need to use very light hammers to go with a higher action ratio (or compromise the blow distance). One thing that would be nice would be to establish the relationship between the Stanwood weight ratio and the distance ratio (since they don't currently match) so that regulation specs could be targeted using weight ratio as the standard. However, since both numbers are easy to calculate it doesn't present that much of a problem. I'm not sure all this is all that accurate. One has to remember that Stanwoods weight ratio is all in all an entirely different puppy then the distance ratio as given by for example Ron Overs on his website. Stanwood does two things that are not really compatible with the distance ratio and can explain why the SWR can be the same for two actions of different distance ratio. Number one, he throws out the individual ratios of the top two levers in the action and combines them into one quantity. Then this quantity is never really used directly in his formula but is rather factored out to arrive at his equation of balance ratio. (see my article on dissecting his equation from a couple three years back in the Journal) Secondly... his equation is that of the ratio of the SW to that of the combined weight of BW + FW - WW where WW is the whippens radius weight times the key ratio. It is not a direct ratio such as the distance ratio which is the ratio of hammer movement to that of the key movement. It is clear that one can achieve identical distance ratios for the upper two arms using various combinations of the individual arms. Choice of individual arm lengths affects the speed of each of the parts in each individual arm and the speed of the individual arms themselves. This illustrates part of the difficulty in attempting a translation from one type of ratio to the other. The end balance weight ratio... or SW ratio as Stanwood has termed it is not porportional to either a standard distance ratio or any given speed ratio. The only relationship that does exist without further ado is that if one increases or decreases any given action ratio through some or another manipulation, one will indeed alter all other action ratio measurements in the same direction. That is to say if you increase the SW ratio, then you will increase the distance ratio and the speed ratio as well. How much in each case is a bit more complicated. Another thing,... a change in the SW ratio by no means necessarily implies a significant change in action regulation specs. One can alter the SW ratio quite a bit and end up requiring no more then a couple mm change in blow distance to achieve same aftertouch for same key dip and same letoff/drop. Cheers RicB
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