Your problems can stem from one or all of the following; Rep lever center pin too loose, repin. Hammer too light for and/or Touch weight too light or too heavy. Too tight pinning or excess friction in key bushings. Backchecks too vertical. If the hammer is too light the key may have too much lead causing too light touch. If the hammer is too light and the key is too heavy the upweight will be too light. I would first look at the rep. lever pin and repin so there is discernible resistance, by finger, of something like 3 or 4 grams. In your lap play a not so it goes into check and tap the top of the hammer. If it move deeper into check the backcheck top is too is too far forward. Bend the wire up under the block then bend it forward as usual and check again. If you go too far the hammer will not go into check. Make sure the hammers have a properly arched tail and they are not too short (3/4 shank bottom to tail end). If this is the problem then the tails may have to be extended then properly shaped or better still replace the set. Key weighing is another big can of worms but it is all doable. Newton
This PTG archive page provided courtesy of Moy Piano Service, LLC