How Do They Make Cast Iron Frames in Pianos?

Every piano has one. It is the backbone to structural integrity. It’s also what gives a piano most of its weight. What is it? Commonly called the frame, harp or plate, this iron mass in the piano withstands the 19+ tons of string tension. Read this month's blog on how they cast iron frames for pianos.http://pianopricepoint.com/casting-iron-piano-frames/