How to Clean a Trumpet. A good internal cleaning will keep your trumpet sounding great.
Prepare the Work Area
Reserve the bathroom or any other room with a tub and running water. A large wash tub and a water hose in the back yard will work fine if it's safe from the curiosity of your pet dog.
Set up a work table near the tub.
Close the bathroom sink's drain, and place a 2- or 3-foot-square piece of plywood over the sink.
Find two Turkish bath towels in good condition. Avoid using worn towels with holes or tears in them.
Fold one towel twice or more so it will form a thick pad to protect the valves and delicate tubes of the instrument.
Place the towel on the bottom of the bathtub. Be sure it covers the drain hole.
Fold and place the other towel on the tabletop or the plywood covering the sink. The work area must be clean and supply cushioning.
Find a comfortable chair or stool.
Make sure that the light sources are adequate.
Get a gooseneck halogen lamp that will illuminate the interiors of small parts.
Fill the tub with 6 inches of lukewarm water and add a 1/2 cup of mild liquid soap.
Mouthpiece, Slide and Piston Valves
Gently remove the mouthpiece with a slight twisting motion of the hand (no pliers allowed) to the left. (If it's stuck, see "How to Remove a Stuck Mouthpiece From an Instrument" under Related eHows.)
Place the mouthpiece on the work area towel.
Apply a slight bit of pressure on the main tuning slide (where the spit valve is located) by hooking the right thumb on the inside curve of the slide and placing the remaining four fingers around the outside end of the trumpet bell.
If the slide is stuck, put three drops of penetrating oil on the two points where the small slide enters the larger.
Try removal again after 15 to 30 minutes.
Remove the tuning slides for the first, second and third valves in the manner described above.
Apply penetrating oil to the screw-off hubs at the base and top of the three piston valves.
Gently unscrew these six hubs.
Carefully unscrew the three finger-pearls at the top of each piston.
Place the three finger-pearls and six hubs on the work area towel.
Slowly withdraw the three pistons out of their casements. Place them on the towel.
Determine the location of the three valve springs.
Handle the pistons so the top felt or cork cushions remain intact with any hardware sleeves.
Immersion, Soak and Flush
Immerse the trumpet and the loose tuning pipes in the lukewarm soapy water.
Turn the instrument several times to insure all tubing has water penetration.
Allow the horn to soak for a minimum of 4 hours or as long as overnight.
Take the tubing to an outdoor location.
Fit a garden hose with a spray-gun valve.
Wrap a towel around the end of the hose. Place the hose-gun covered with the towel into the bell of the horn.
Flush out the buildup on the inside of the tubing with a strong stream of water.
Repeat this procedure with each trumpet tube.
Use a small "snake" with a small brush on the end to loosen rebellious dirt. Flush again.
Carefully rinse, dry and re-oil all parts. Blow the water out of all tubing.
Reassemble the instrument, taking special care on the re-insertion of the valves.
Take the horn to the racetrack for a trial run.
Check the trumpet to determine if all the parts are complete, undamaged and intact. Blow through the instrument, depressing all three valves, to discover any blockages. Put a clean wash rag in the end of the bell to seal the air chambers. While blowing to create some air pressure, open and close the main tuning slide spit valve to determine how well it prevents air leakage when under pressure. Press the third valve, blow air, and open and close that spit valve. Does it seal? If there is leakage, fresh corks should be installed. Remove the rag in the bell and produce a sound, if you can. Run a chromatic scale. Listen for the half/step note changes for accuracy and quality of tone produced. If there are leaks in the valves or the tuning slides, the tone quality will be inferior and compromised. Dry each part you've removed and place it on the work area towel in an organized manner. Inspect the outside surface of the piston for any scars or dents. Do the same for the inside and outside of the casements. Your local music store owner can often be of immense help. He usually works closely with the private and public-school music teachers. Instrument manufacturers are helpful in supplying information regarding franchise locations and representatives. It is ultimately to their benefit.
Used and old instruments can harbor infectious bacteria. Be careful about how quickly you place your lips on old or used mouthpieces. Disinfect them using an alcohol soak, or use your own mouthpiece. If you are checking an instrument for potential purchase, be sure all the slides and valves move and function with ease. Dented slides and "frozen" slides are expensive to replace. Avoid using strong force when attempting to remove slides. Pliers used to remove a mouthpiece will often twist the lead-pipe into a closed S-shape position. Lead-pipe replacement is expensive. External-style valve springs can easily drop out of a casement or be mislaid. If air won't pass through the tubing after reassembly, one or more of the valve pistons have been inserted improperly. Loosen the top valve shoulder hubs. While trying to blow air through the instrument, rotate each valve until proper alignment is located. The first and third valve pistons may be in the wrong casements. Try switching them until air passes through the horn freely with the valves down and up.