Covering wire tightening device composite strings of pianos

摘要

Device for tightening a coiled covering wire of a composite piano string relative to the core wire thereof comprises a spring-loaded operating shaft axially movably encased within an elongated cylindrical main body, the shaft being provided with an outwardly exposable end portion adapted for detachable engagement with the top of a frame pin so that the composite piano string can be transferred to the shaft for twisting. Adjustment of the winding strength of the covering wire relative to the core wire is greatly simplified and stabilized.