Hi Alan To begin with, you can not use the Stanwood balance formula for this, not directly anyways. That formula is based on measuring a several weight quantities and one ratio quantity first. The nett effect of a knuckle move is somewhat dependant on the ratios of both the whippen and key, but generally speaking you get about a 3-4 gram change for a mm movement. Moving towards the hammer of course decreases the weight, and away from the hammer yeilds an increase. The nett effect of a capstan move is dependant on the existing key ratio itself... but a 1 mm move results in somewhat less then a grams change either way as a general rule. The thing is you are dependant on knowing the exact ratio of each part and the action as a whole to do directly what you want. Since you are relying on distances this means taking into account all the relavant angles of the parts with the action in the position of equilibruim. (BW). If you know all these.. then you can accuratly calculate exactly what a given move yeilds in terms of a BW change. But this is not the easiest of things measure on the bench which is probably half the reason Stanwood came up with his alternative. Cheers RicB > <><>Hi Folks, > > I'd like to pick some of your brains about a problem action. I thought > it might help the discussion to include my spreadsheet, but the list > administrator thought it better to separate the attachment. If you wan > to,please go to http://www.ptg.org:1406/files/20041019125312.xls for > the worksheet. Is there some way to calculate how much BW will change > when moving either the knuckle or the capstan? Or does anyone have > enough experience/data for rule of thumb for this calculation? > Comments? Thanks. > <>-- Alan McCoy, RPT
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