The flute is a woodwind instrument that creates sound when a stream of air is blown across the mouthpiece. This creates a vibration that results in a musical tone. The body of the flute has a series of holes that affect the sound of the flute when covered or uncovered. On the modern flute, the holes are covered with key caps, each of which contains a pad that will fully block the air, though some older flutes have finger holes as well. To replace flute pads, the old ones must be removed and new ones put in the key caps, then adjusted until each fits properly.
Flute pads are essential to the operation of the flute, since they regulate the air flow and thus control the sound. Missing pads are an obvious problem, because the flute won’t play properly, but worn, aging, or damaged flute pads can cause a range of more subtle sound problems. Once the pads will no longer seal the air holes on the flute properly, they must be replaced.
Sometimes the old pad is lost, so there is no need to remove it, but if the old pad is still in place, it must be taken out of the key cap before the new one can be installed. Generally, this means that the keys must be removed from the flute so that the inside of the key caps can be accessed and the flute pads can be replaced. It is important to keep track of every screw, key and lever that is taken off of the flute, so that each can be returned to its correct spot after the pads have been replaced.
The old flute pads are removed by taking off the plastic button in the center of each pad, then lifting the old pad out of the cap. Underneath the pads are cardboard washers that are used to level the pads and make sure they fully cover the holes. Any worn washers should be replaced, then the new flute pad is placed on top of the washer and checked to make sure it is level. Some flutes have a screw under the pad that can be adjusted to level it, while others depend solely on the washers. The plastic button is then put back in place to hold the pad.
Once the pads have all been replaced, the keys should be returned to the flute and checked again to make sure they are level and fully close each hole. If not, the keys must be removed and adjusted again, either with the leveling screw or by adding or removing washers under the pad. Once the flute pads are all installed and cover the holes properly, the process of replacing the pads is complete.