How to Clean Brass Instruments

Click HERE to view a Youtube video on how to clean a trumpet. This video shows a trumpet. Giving a bath to a trombone, euphonium, or tuba will be very similar. You should give your brass instrument a bath 2 times per year (and never, ever the night before an important concert!).

If you play French Horn, use THIS LINK for a special video on giving your horn a bath. Remember to take a picture of both sides of your horn before taking it apart, this will help when you re-assemble everything.

In addition to watching the video(s), please read through the description below and feel free to email Mr. Monkman ( if you have questions.

All brass instruments must be given a bath 2-3 times a year. The whole instrument should be immersed in a warm bath of soapy water. Remove all of the slides and valves (for the French horn, only remove slides) before immersing. French horn slides should be kept in two separate groups (top slides/bottom slides) and you should take a picture of the instrument on both sides to help with re-assembly. Immerse the slides. Dip the valves into the water and swirl without getting the felts wet. After leaving all the parts to soak use a valve brush and a flexible cleaning brush (snake) to clean all of the tubing. Flush all the parts with clean water, then dry with a soft cloth. Lubricate all slides using petroleum jelly/slide grease and lubricate all valves with valve oil and refit to the instrument wiping off all excess oil/grease from the slides.


Make sure you have the following items before beginning: (a) Polishing Cloth (b) Drying rag (c) Valve/Slide Oil (d) Slide Grease (or unscented petroleum jelly) (e) Mouthpiece Brush (f) Snake Brush (g) Valve Brush – trumpet/euphonium (h) Cloth Towels

Bathing the Instrument
1. Disassemble your instrument – first remove all valves, and pull all slides and remove valve cap bottoms. (Trumpet/euphonium valves must be set aside and cleaned by hand. These valves are not interchangeable so we suggest using a sheet of paper to label each valve (1st/2nd/3rd) Do not disassemble trumpet valves.) *French horn slides must be divided into two groups (top and bottom slides). Use a sheet of a paper to label each slide and keep these slides separate while cleaning. If these slides are not placed back in the correct order the French horn will not produce the correct pitches*

2. Fill a bathtub with lukewarm water and add ¼ cup of mild hand soap. Place the disassembled parts in the water on top of towels or rags so the instrument does not get scratched.

3. Allow your instrument to soak for 20-30 minutes. Trumpet/baritone valves should be cleaned by hand at this time. Use the valve or mouthpiece brush with a small amount of water and a squirt of tub and tile cleanser (such as Kaboom). Valves should be inspected for corrosion or damage. Once clean, set them aside. Remember: the valve number is stamped on the brass near the spring. Valves must be put back in their valve casings in order.

4. Using the snake brush and valve brush, scrub the inside of all tubing. Run water through tubing and repeat until it comes out clean.

5. Rinse the instrument clean of soapy/dirty water. If possible attach a hose to your sink and run water at high pressure through each open slide receiver and the bell. Remove the instrument from the bath and dry off everything with a clean towel. Be sure to spin the instrument several times to ensure that all water has been emptied from the tubing (especially French horns and baritones).

6. Apply a thin layer of slide grease (petroleum jelly) to slides and reassemble them into the body of the instrument. Wipe off any excess grease. Apply oil to piston valves and reassemble them in order.

7. Polish your instrument with the polishing cloth once it is dry. This will remove any water stains you might have missed.

8. Play test your instrument and empty any excess water with the water keys. Trumpets will not be playable if the valves were reassembled in the wrong order, or not aligned in the valve casings.


Just in case you wanted to read more about cleaning brass instruments, here’s another description of giving your instrument a bath:

· Bathtub

· Margarine bowl or other small plastic bowl

· Towel

· Soft 100% cotton cleaning rag

· Dishwashing detergent

· Toothbrush

· Cotton swabs

· Soft 100% cotton towel to dry horn

· Assortment of brushes – mouthpiece brush, leadpipe brush, snake, and a valve casing brush for valved instruments. Specialized brushes or cleaning kits can be purchased from your local music store for your specific type of horn and they are a good investment. Follow these steps to get the most out of your horn:

Take your horn completely apart and clean it thoroughly. Make sure you have plenty of space to do this and it is very well lit. It is best to have a plastic bowl to keep all small parts like valves, valve springs and valve caps.

Place a towel in the bottom of your bath tub and lay the disassembled horn (minus the really small pieces) on it. The towel keeps any abrasives from scratching the finish of the horn.

Fill the tub with about 8-10 inches of lukewarm water. Next pour a couple tablespoons of dishwashing soap in the water and mix it up with your hands. The two best brands of soap for cleaning your horn are Palmolive or Joy. Other brands tend to leave a residue on the horn after it is rinsed. Let the horn soak for a few minutes to loosen any gunk, then use a valve casing brush to clean valve casings by dipping the valves in water, keeping the felt at the top of the valve dry. The snake and the mouthpiece brush should be used to clean the slides and tubes of the rest of the horn.

For smaller parts, like valve end caps, use cotton swabs to remove dirt, grease and foreign bodies. If you cannot remove dirt from end caps and old toothbrush can be used. You should avoid using toothbrushes on precision parts like piston valves and trombone slides as they may damage them.

Thoroughly rinse the horn and smaller parts to remove any soap residue. Dry the horn with a soft cotton cloth.

Check with your director or local repair shop for any special instructions for bathing your horn. Some finishes (silver) require special care.

Spend a little time going over your horn when cleaning it. This will allow you the opportunity to find any problems that need to be addressed. It is not uncommon for problems to develop with trombone slides, turning slides and water valves during the school year. If you thoroughly clean your horn at least twice a year, you should be able to identify the problems and get them fixed before they become major issues.

Everyday Maintenance:

Clean the mouthpiece with a brush every couple days. Long hours of playing cause them to get dirty, sweaty, etc., and keeping them clean keeps the horn cleaner longer as well. A horn will collect a lot of dust and dirt over the course of a year. Small particles of dust and sand readily stick to oiled parts like trombone slides and micro close tolerance piston valves. Add a drop or two of oil each day on every piston and slide.

Take care of your case. The purpose of your horn case is to protect your horn, but if your case is damaged, it may not be able to do its job properly. Also, refrain from stuffing a lot of objects other than your horn in its case. The case your horn comes in was designed specifically for that type and model of horn. Do not carry band music or lesson books inside your case. Putting books and/or music in your case with your horn and then closing it can put pressure on your slide and cause it to bend. Putting a lot of extra items in the case with your horn could scratch the finish or worse.