Regilding the Plate

Before the piano soundboard or pinblock can be replaced, the plate must be removed. It also should be removed if the plate is being regilded.  The plate is an assembly of cast iron. (Some people also call it the "harp" or "frame.") In most pianos it is a one piece casting. In grand pianos, and also in many verticals, it is painted gold.  The purpose of the plate is to help the piano withstand the tremendous tension of the strings.  In the the photo Plate1.jpg we are removing the plate from a concert grand with a crane.    In a piano of this size and type, each string is under approximately 130 to 200 pounds of tension when tuned to pitch.  When multiplied by the total number of strings, approximately 240, the tension of all the strings combined can be close to 40,000 lbs. or 20 tons.  When new strings are put on a piano, or when the old ones are taken off, we take great care to raise or lower the tension uniformly over all the strings so that the plate will not crack.  The plate itself can weigh as much as 800 lbs.