Do you have chipped piano keys??? They can be filled with Acrylic at a fraction of the cost of new keytops. . . Hammer Filing and Voicing will greatly improve the sound on this fifty year old vertical piano. Replacing Key Bushing Felts tightens loose/sloppy keys. Rebushing keys can greatly improve the touch and the enjoyment in piano playing. Replacing Newly Bushed Keys in the Piano This historic grand piano damper action needed tightening and regulating after some dramatic swings in humidity.