Dear Tom, My angle on things is from the "component analysis" side of things. What protocol did you use for measuring Up and Down Weight? (Normally I would first correct any obvious geomtery problems before measuring up and down weight.) A little data analysis helps. Calculate Friction Weight as F=(DownWt-UpWt)/2 Calculate Balance Weight as BW=(DownWt+UpWt)/2 Results: Note Number Down Wt UpWt F BW 16 C2 53 34 9.5 43.5 28 C3 57 36 10.5 46.5 40 C4 60 36 12.0 48.0 52 C5 64 38 13.0 51.0 64 C6 62 38 10.5 48.5 76 C7 62 39 11.5 50.5 87 B7 75 41 17.0 58.0 Analysis: Rule of thumb: Friction Weights below 10 grams or above 15 grams are abnormal. So note 16 is low and 87 is high. Anything abouve 40 Balance Weight is abnormally high and everything here is. Note 87 is way different from all the others. Back lead in the key? The only way I know of to assess hammer weight "on the shank" is by measuring Strike Weight: http://www.stanwoodpiano.com/swsetup.gif Then check the data against the chart of Normal Zones: http://www.stanwoodpiano.com/swranges.jpg So how much lead is in the keys? David C. Stanwood
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