If you own a Yamaha Console piano that is 20-30 years old, you may have noticed that certain keys depress easier than others. This is most likely because the tiny thread that holds the hammer return spring, has dry rotted and released the spring. Those keys may also “click” as the free spring hits other parts. The key may also “dribble”…that is, hitting the strings several times on one keystroke! The repair involves replacing all the the hammer flanges, and with them, the new retaining thread. The new thread is polyester and will last the remainder of the piano’s life. While this repair typically costs $500-600., it is well worth it since these are otherwise very reliable pianos, with no other parts that fail in that manner. Also consider the cost of new Yamaha ($7000-8000), and this repair cost now seems negligible.