The Factors Determining the Scale
Tuning Pins, Pin Block



Tuning Pins

• A tuning pin must fulfill several functions: it must be so tightly seated in the pin block that it will not slip and release tension from the string. However, it cannot be so tight that it cannot be properly moved by the tuner in the tuning process. Lastly, the pin must remain stable and fulfill those requirements for many, many years.
• How well the tuning pins are seated in the pin block is one of the major factors that determines how well the piano will stay in tune.
• Tuning is done by changing the tension of the strings, and is carried out by rotating the pins either clockwise or counterclockwise. Any increase in the string tension will raise the pitch; lowering the tension will lower the pitch.



Pin Block

• The tuning pins are seated in this board. It must hold the pins solidly, withstanding the approximately 90 kg string tension on each pin without loosening.

Materials

• The tuning pins are made of steel, chose to fulfill the needed functions.
• Maple wood is used for the pin block. The strength of the pin block is further increased through the construction process used to laminate the layers of maple together with the grains of each alternate layer at right angles to each other. Maple has been found to be ideal for this application.
• To prevent the tuning pins from rusting, Yamaha either electroplates them with a layer of non-rusting metal such as nickel, (creating a white or silver colour); or heat-process them to crate a surface layer of non-rusting oxide (creating a blue colour) or heat-process them to crate a surface layer of non-rusting oxide (creating a blue colour).
• Yamaha's oxide coating, rust-proof processing technology was developed after much research and experimentation, and is as effective nickel plating against rust.



Design and Fabrication





• The upper portion of the tuning pin is squared off on four sides to allow the tuning hammer to grip it firmly. The lower portion (the section seated in the pin block) has "threads" cut into it to produce the friction necessary to prevent slippage.
• A major point concerning tuning pins is that their manufacture needs to be very precise and consistent. Although the holes can be drilled in the pin block with highest precision, the tuning pins will not hold correctly if they are inconsistent in diameter, even the smallest amount. The piano will go out of tune quickly, and the job of tuning is made difficult.
• Yamaha tuning pins are produced in-house using our self-developed, specialized machinery. The precision is exceptionally high and as a result the pins are very accurate and uniform. (Machining precision: within a tolerance of 2/ 100mm).
• The seasoning process of the wood used in the pin block is a very important factor in determining how securely and how long the pins can be held correctly. Yamaha administers very strict controls concerning the moisture content during seasoning and manufacture.