Why do Yamaha pianos use plastic parts? It is said that it is Yamaha's patent.

To tell the truth, domestic Yamaha has no technical relationship with imported Yamaha. Domestic Yamaha is only a domestic OEM production, because the piano is not cast by Yamaha technology, so there are hidden dangers of stability. In China, Yamaha can only prevent the steel plate from breaking and directly make it into a quadrilateral. In fact, if the technology is in place, the triangle is the most stable and is designed according to the arrangement of strings. Domestic Yamaha has little to do with Japan except that its brand is Japanese, so it is not recommended to consider Yamaha.