Brass Essentials
Brass instruments for the student usually require less maintenance and repair than do their woodwind counterparts. Generally it is because there are less moving parts, and the parts are internal rather than exposed.

Brass instruments are also more user serviceable. Students are taught to oil the valves and grease the slides themselves. Also, with the purchase of a care kit and instructions, brass students can do more elaborate cleaning by giving their instrument a “bath.”

There are, however, things to consider and evaluate regarding whether or not your instrument should come to the repair shop.

Dents:
Dents in the tubing are gauged by how far they close down the bore. Any dent in one spot that closes the bore by twenty percent is seriously constricting proper airflow.

Dents in the bell will stress the brass and constrict the metal from vibrating in the way it was designed to. This affects both tone and intonation.

There is no dent that is purely cosmetic; however, there is a range of affect that should be judged by the player, the teacher, and the technician.

Cleaning:
Brass instruments are “closed bore.” This means that aside from the water key, there is no place between the mouthpiece and bell where there should be any hole or break in the tubing. This also means that various materials can build up on the interior of the tubing walls and constrict the bore.

Giving your instrument a bath periodically will keep the bore clean of organic material, which can also harbor bacteria. Over a longer time, mineral deposits such as lime and calcium will build up inside the tubing. These cannot be cleaned at home and must be brought to the shop for professional removing.