Take careful up and down measurements of all the "C"s and all the "C#"s. Break the static friction by knocking on the action with your hand. Carefully clean the action, polish (use super fine metal polish like Flitz) and lubricate the key pins, capstans, rocker cushions and the wippen tops under the knuckles. Regulate the action carefully then remeasure the up and down weights. Half the difference between the two is the friction. That should go down into the 10 to 12 gram region in the base and into the 6 to 8 grams in the treble. The average of the two is the balance weight and it needs to be in the 35 to 40 gram range. If it is lower it will not repeat well and if it is higher it is "over weight" and more serious looks at the geometry and other measurements need to be made. Start with this and report back when you get the first set of measurements. Newton
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