<< Bill Spurlock on the other hand suggested the rate (relating to wire guage, coil, etc.) of the springs is closely engineered to match the weight of hammers, providing a wide range of effective adjustments. Major changes in hammer weight however, take the springs outside their "predictable" range of adjustment/response. I can see both having a factor, in that firm pinning (this center needn't be as free as the others) in the rep. lever will have a moderating effect on the action of the rep. spring. >> It is also wise to check the hammerflange pinning. If it is loose, the spring is going to be set weaker than design specs. In combination with a loose balancier pin, the spring may be far weaker than it was originally intended. Also, if there is friction from corrosion in the spring seat,(grub), the action on the balancier may be atypical when winking the jacks. Also consider the factors such as lack of proper lubrication on jack tip as well as aberrations on the leather of the knuckle. A slight bump on the knuckle will prevent the smooth return. I have had the majority of problems with this phenomenom on Baldwin pianos and others with the Schwander configuration. Regards, Ed Foote RPT http://www.uk-piano.org/edfoote/index.html www.uk-piano.org/edfoote/well_tempered_piano.html
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