Different Kinds of Piano Materials


Many parts of a piano are made of materials selected for extreme sturdiness. In quality pianos, the outer rim of the piano is made of a hardwood, normally maple or beech. According to Harold A. Conklin, the purpose of a sturdy rim is so that "the vibrational energy will stay as much as possible in the soundboard instead of dissipating uselessly in the case parts, which are inefficient radiators of sound."

The rim is normally made by laminating flexible strips of hardwood to the desired shape, a system that was developed by Theodore Steinway in 1880. The thick wooden braces at the bottom (grands) or back (uprights) of the piano are not as acoustically important as the rim, and are often made of a softwood, even in top-quality pianos, in order to save weight. The requirement of structural strength, fulfilled with stout hardwood and thick metal, makes a piano heavy; even a small upright can weigh 136 kg (300 lb), and the Steinway concert grand (Model D) weighs 480 kg (990 lb). The largest piano built, the Fazioli F308, weighs 691 kg (1520 lb).

Upright Pedal Piano - Piano Materials

The pinblock, which holds the tuning pins in place, is another area of the piano where toughness is important. It is made of hardwood, (often maple) and generally is laminated (built of multiple layers) for additional strength and gripping power. Piano strings (also called piano wire), which must endure years of extreme tension and hard blows, are made of high quality steel. They are manufactured to vary as little as possible in diameter, since all deviations from uniformity introduce tonal distortion. The bass strings of a piano are made of a steel core wrapped with copper wire, to increase their flexibility.

The plate, or metal frame, of a piano is usually made of cast iron. It is advantageous for the plate to be quite massive. Since the strings are attached to the plate at one end, any vibrations transmitted to the plate will result in loss of energy to the desired (efficient) channel of sound transmission, namely the bridge and the soundboard. Some manufacturers now use cast steel in their plates, for greater strength. The casting of the plate is a delicate art, since the dimensions are crucial and the iron shrinks by about one percent during cooling. The inclusion in a piano of an extremely large piece of metal is potentially an aesthetic handicap.

Piano makers overcome this handicap by polishing, painting, and decorating the plate; often plates include the manufacturer’s ornamental medallion and can be strikingly attractive. In an effort to make pianos lighter, Alcoa worked with Winter and Company piano manufacturers to make pianos using an aluminum plate during the 1940s. The use of aluminum for piano plates, however, did not become widely accepted and was discontinued.

The numerous grand parts and upright parts of a piano action are generally hardwood (e.g. maple, beech. hornbeam). However, since World War II, plastics have become available. Early plastics were incorporated into some pianos in the late 1940s and 1950s, but proved disastrous because they crystallized and lost their strength after only a few decades of use. The Steinway firm once incorporated Teflon, a synthetic material developed by DuPont, for some grand action parts in place of cloth, but ultimately abandoned the experiment due to an inherent "clicking" which invariably developed over time. (Also Teflon is "humidity stable" whereas the wood adjacent to the Teflon will swell and shrink with humidity changes, causing problems.) More recently, the Kawai firm has built pianos with action parts made of more modern and effective plastics such as carbon fiber; these parts have held up better and have generally received the respect of piano technicians.

The part of the piano where materials probably matter more than anywhere else is the soundboard. In quality pianos, this is made of solid spruce (that is, spruce boards glued together at their edges). Spruce is chosen for its high ratio of strength to weight. The best piano makers use close-grained, quarter-sawn, defect-free spruce, and make sure that it has been carefully dried over a long period of time before making it into soundboards. In cheap pianos, the soundboard is often made of plywood.

Piano keys are generally made of spruce or basswood, for lightness. Spruce is normally used in high-quality pianos. Traditionally, the black keys were made from ebony and the white keys were covered with strips of ivory, but since ivory-yielding species are now endangered and protected by treaty, plastics are now almost exclusively used. Also, ivory tends to chip more easily than plastic. Legal ivory can still be obtained in limited quantities. At one time, the Yamaha firm innovated a plastic called "Ivorine" or "Ivorite", since imitated by other makers, that mimics the look and feel of ivory.

2 Responses to “Different Kinds of Piano Materials”

  1. Angela Valueton 18 Jun 2008 at 1:01 am


    I would like to ask a question. The color of black keys on my piano is fading away. I would like to repaint them but do not know what kind of paint can be used. Would you please recommand?

    Thank you very much.


  2. adminon 18 Jun 2008 at 1:45 am

    Typically paint is not used, you really need to replace your key tops. I found this page that should give you more information: http://www.stevespianoservice.com/36-keytp.htm

    hope it helps!


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