How to Fix a Trumpet's Keys

Consisting of brass tubing wrapped into an oblong shape, the trumpet has the highest register, or range of sounds, of any brass instrument. Air blown into a removable mouth piece travels around inside the tubes and through hollow chambers that are open and closed by spring-loaded pistons. The pistons, controlled by the trumpet's keys operated with the fingers, can dry out or become gummed up from buildup inside the horn, causing the keys to stick. To fix a trumpet's keys you must disassemble the pistons.

Things You'll Need

  • Clean cloth
  • Instrument valve oil
Show More

Instructions

    • 1

      Remove the trumpet's pistons one at a time. Unscrew the cap atop the chamber of the first piston, closest to the mouth piece, with your fingers. Pull the piston and plunger assembly from the horn.

    • 2

      Wipe all surfaces of the piston with a clean, soft, lint-free cloth.

    • 3

      Apply two drops of valve oil to the side of the piston. Work the oil evenly over the entire exterior surface of the piston with a finger.

    • 4

      Insert the piston back into the chamber. Wiggle the button at the top of the plunger back and forth until you hear a click, indicating the valve guide on the piston has dropped and locked into the valve guide slot inside the chamber.

    • 5

      Screw the cap of the plunger assembly back onto the top of the valve chamber, finger tight. Never use tools to tighten the piston caps.

    • 6

      Work the plunger several times with your finger, confirming the plunger is working freely.

    • 7

      Repeat the procedure with the other valves.