The trombone belongs to the brass family of musical instruments and typically consists of four major parts — the inner slide, outer slide, tuning slide, and bell. Each time the trombone is played, dirt accumulates on top of and inside these parts, so it must be cleaned regularly to keep these moving smoothly and maintain the instrument's playability. When cleaning a trombone, it is important to treat each piece with care and use the appropriate cleaning fluids. Additionally, a good cloth should be used, and the instrument should be lightly cleaned daily and given a bath at least once a month.
Each part of the trombone must be free from dents and other imperfections to ensure that the instrument will play well. When cleaning a trombone, it is sometimes necessary to take the trombone apart and clean each of the pieces individually. To prevent a piece from becoming dented or warped, each piece that isn't in the process of being cleaned should be placed in the trombone's case or on a hard, flat surface that is above ground level. This protects the trombone's parts from being stepped on, sat on, or falling down.
While cleaning a trombone, each part should be handled with great care. It should not be held too firmly, since this can cause the metal to warp. If the trombone is being cleaned on or above a hard surface, placing a large, soft towel on the surface should prevent the trombone from getting scratched, and provides cushioning if the trombone slips out of the cleaner's hands.
Mild, liquid dishwashing detergents are suitable for cleaning a trombone. Trombone players usually mix one to two drops of liquid detergent with lukewarm water when cleaning a trombone, to remove dirt and oil from the inner and outer surfaces of the instrument. Hot water should not be used, since it might strip the protective lacquer coating.
Since trombones typically have shiny and smooth surfaces, it is important to clean them with soft cloths. Those made from microfibers, such as eyeglass cleaning cloths, and those with high thread counts will clean the trombone without scratching surfaces. Rough cloths and towels should be avoided.
In addition to cleaning the trombone with a cloth, a cleaning snake and mouthpiece brush are also required. A cleaning snake consists of a long, flexible tube with a scrubber on each end, and the mouthpiece brush resembles a typical cleaning brush. The cleaning snake is used during baths to remove grime inside the trombone's tubing. It is much more effective at removing dirt and grime than water and detergent alone. The mouthpiece brush is used to regularly clean the instrument's mouthpiece, to ensure it plays well and to ensure proper hygiene for the player.
To keep a trombone in good playing condition, it should be cleaned daily, or at the very least, after each playing session. Daily cleanings take only a few minutes and can be performed with a cloth and mouthpiece brush. Everyday cleaning removes dirt and grime from the contact — or outer — surfaces, including the mouthpiece. Daily cleanings are performed by pushing and pulling the mouthpiece brush in and out of the mouthpiece, and then wiping the trombone with a cloth.
Baths are used to clean both the inner and outer surfaces of the trombone and should be performed at least once a month. Before giving the trombone a bath, it must be taken apart. Each piece is then cleaned with lukewarm water and detergent, and a snake is used to remove grime from the tubing. Giving the trombone a bath in a bathtub or shower tends to be easier than bathing it in a sink. After bathing, the tuning and hand slides should be oiled with a special trombone lubricant.