French Horn Cleaning and Maintenance [Complete Guide With Pictures]


Compared to some instruments, horn maintenance isn’t difficult. Since rotary valves are not user servicable, though, it is important to do some basic things on a regular basis

One of the most important rules for a clean, functional horn is good oral hygiene.

If possible, avoid eating or drinking anything (except water) before playing. If you must eat or drink, make sure to brush your teeth (or at least rinse your mouth with some water) before playing. Remember that slide and valve tolerances are measured in thousandths of an inch – it doesn’t take much to slow them down.

Oils to Use on Rotary Valves

As far as which lubricants to use, you do have quite a few options:

I prefer Blue Juice for the inside of rotary valves, and Hetman lubricants for the bearings and linkages.

In general, you want to use something light for the inside of the rotary valve. Piston valve oil (like Blue Juice, Al Cass, or similar) is totally fine. Stuff labeled “rotor oil” that has the needle oiler (like Hetman 13, Superslick, or similar) is meant for the rotor bearings. There’s even thicker stuff used for the lever springs or mechanical linkages (Hetman 14 and the even-thicker Hetman 15).

One of the reasons I’m such a fan of Hetman is the very clear numbering/viscosity system. It’s very straightforward, so if you find that you need something a bit thicker (reduce noise/end play at the expense of speed) or thinner (for newer valves or for more speed) it’s very easy to get the right oil. Also, since they are all synthetic, you can even mix them – if #14 is too thin, and #15 too thick, you can mix them to have something in-between.

Some people like to use more general-purpose lubricants. The most often recommendations I hear are for lamp oil for the inside of the valve, and 3-in-1 machine oil for bearings and linkages. Keep in mind since these oils are all petroleum-based, you can also mix these to get different viscosities. As it come, 3-in-1 is a bit thick, but mixed with some lamp oil it becomes quite nice.

One of the main disadvantages to using some of these petroleum-based lubricants is that they generally have a noticeable odor. It bothers some people but not others, but just be aware of this.

How to Oil Rotary Valves

There are a few different places that you need to oil rotary valves: the top bearing, the bottom bearing, and inside the rotor itself. The top and bottom bearing are easy to oil, and if you keep them well-lubricated you don’t have to mess around with the interior much at all.

Oiling the Top and Bottom Bearing

The top bearing is the simplest and most obvious place to oil.

Simply remove the cap and place a drop or two on the top of the rotor bearing.

oil the upper bearing

The bottom bearing is a little trickier to get to.

This bearing is why rotor oil comes with a needle tip (you can also purchase needle tipped bottles if your favorite oil doesn’t come in one). You want to get the oil where the spindle goes into the valve casing. It’s a bit hard to see in this picture, but the small gap is what you’re aiming for.

French horn cleaning lower bearing
Oil for the bottom bearing goes right where the spindle meets the valve body.

Don’t try to use a normal bottle of valve oil to get into this space. You’ll make a pretty huge mess (and waste a lot of oil). Make sure you get the right tool and the job becomes much easier!

For most horns, these bearing should be oiled a few times a week. There’s no “right” answer here, you have to go trial and error. In general, it’s better to oil a little too much than too little, though. I oil my horns about 2-3 times a week. Sometimes more if they are played in hot conditions (outside during the summer or under bright stage lights).

I’ll also make sure to oil them a bit more than average if I have to put them down for more than a few days (which rarely happens). When you’re playing your horn regularly, the moisture in your breath helps keep things lubricated, and if you leave the horn in the case for days or weeks (especially if it’s warm) then that moisture can evaporate and the rotor can get stuck easily (especially if you haven’t been brushing your teeth before playing.

Oiling Inside the Rotors

Once every week or two (or if the valves feel sluggish) you’ll need to get oil on the inside of the rotors. There are a couple of different ways to do this:

Method 1: Using the Slides

The first way to do this is using the slides:

  1. Pull out your first valve slide (if you have a double horn, pull out both first valve slides) and put 15-30 drops of oil into each slide.
  2. While carefully keeping the slides upright, insert them both back into the horn all the way.
  3. Rotate the horn so that the oil will run down into the first valve.
  4. While rocking the horn back and forth, press down on the valves repeatedly (including the trigger) to make sure the oil gets on all the rotors. 
  5. After you’ve gotten the valves moving quicker (you should be able to feel the difference), empty the horn. Be careful, since the oil will be much slipperier than normal water.

NOTE: It’s very important that you push the slides all the way in when you put them back. If you don’t, you could get slide grease into the valves, which will definitely slow them down.

Then , and while rocking the horn back and forth, repeatedly press down on all the valves (don’t forget the trigger!). There will be a lot of oil in the horn at this point, so be careful when you empty it (or when the horn empties itself on your lap!) – it will be slippery!

Method 2: Using an Eye Dropper

The second way is a bit easier (in my opinion) but does require you to have an eye dropper bottle. Thanks to the magic of Amazon, though, eye dropper bottles are easy to find.

This method is very similar to the first method:

  1. Remove both first valve slides.
  2. Get some oil in the dropper
  3. Holding the horn upright (empty slide legs pointing up), put the dropper as far into the slide leg as possible and squirt the oil onto the rotor.
  4. Repeat for the other (F or Bb) slide leg.
  5. You can either do this for each slide individually, or put 2-3 “servings” in the first valve slides and do the same rocking motion to distribute the oil to other valves.

Either of these methods work well, and are quick and easy to do once you do it a few times.

Remember that rotary valves are much different than piston valves and should not be removed unless you know what you’re doing. Knowing how to work on rotary valves is an incredibly useful (and potentially profitable) skill, but make sure you practice this on a junk horn before you try to work on your (or someone else’s) instrument.

Slide Grease for French Horns

Much like the oils, for greasing your slides you have a few different options.

If you want to stick with Hetman products, they make quite a wide range of slide greases. Like the valve oils, Hetman slide lubricants come in a variety of thicknesses and are categorized by numbers. #7 Slide Gel is for very tight-fitting slides while #8 Slide Grease is a great general-use slide grease for most instruments. If you have loose fitting slides, and need a quick fix, #9 or #10 are much thicker and can help seal a worn slide until you get it to a repair person.

If you play trumpet (or mellophone) and need something lightweight for the first and third valve slides, Hetman also has a slide oil that works great. For horn, though, it’s likely much too thin.

For petroleum products, you have a couple of options.

For instrument-specific grease, the Selmer slide grease was a good and inexpensive option, but it’s harder to find now. Many music stores are selling slide grease in a chapstick-like tube, and I don’t care for that as much. In my experience, it tends to not apply easily and can lead to chunks winding up in the valve slides or (worse) valves themselves.

Like I mentioned for valve oil, there are also lower-cost options not made specifically for musical instruments. The most common are:

  • Vasoline (or any petroleum jelly)
  • Medela Lanolin (or any type of anhydrous lanolin)
  • Bag Balm (mix of petroleum jelly and lanolin)
  • Gun grease – lots of brand choices, but this one is often recommended).
  • Brake grease – lots of options, but this is what I’ve used.

Similar to the oils, each of these have positives and negatives.

In general, petroleum-based greases (Vaseline, Bag Balm) can be thinned out by petroleum-based oils, This means that you may have to apply them more often, but if some gets inside a valve, it’s relatively easy to wash it out. Lanolin can also be washed out with water, so it needs constant application, but is easy to clean off.

The gun grease and brake grease will probably last longer and be more resistant to grease and moisture, but this means that if you apply too much and it works into the valves, it can be a pain to get out. Sometimes requiring a chemical or ultrasonic cleaning.

Needless to say, though, these options are all cheaper per-ounce than the music-specific equivalents.

How to Grease Your Slides

Like oiling your rotors, there are a couple of ways to grease your slides.

My preferred way is a bit messy, but it’s effective and quick. Simply put a small drop of slide grease on both legs of the slide, and spread it around evenly with your fingertip. Once you’ve spread it around on both legs, put the slide back into the horn all the way.

If a bit of extra grease comes out, that’s fine, simply wipe it off with a rag or towel. You’ll probably want to move the slide all the way in and out a few times to make sure it moves smoothly, but you shouldn’t have any mess after the first insertion.

The second way tries to keep your hands clean by avoiding the spreading. Instead of putting a drop or two of grease on the slide, you apply a ring of grease around the end of the slide. The idea is that by putting grease at the tip of the slide, it will be spread evenly when the slide is inserted. This doesn’t always work as well in practice as it does in theory, but if you don’t want to get your hands messy, it’s worth a try.

Usually this method will require you to apply a bit more grease on the slide, which means you’ll have a little bit more to clean up once the slide is inserted all the way, but for some this is a worthwhile trade-off.

Leadpipe/Mouthpiece/Horn Cleaning

Cleaning the leadpipe regularly is one of the best ways to make sure any bits of food or other gunk don’t make it into the valve mechanism.

If you have a standard single or double horn, using a standard trumpet snake brush to clean out the leadpipe about once a month will keep the rest of your horn quite clean.

Aside from a standard instrument snake, the other way to clean out the leadpipe is using Herco Spitballs. These are small sponges soaked in a cleaning solution that can be shot through the leadpipe to quickly get out some dirt and gunk. They don’t clean as well as a snake (in my experience) but they are convenient and a bit of fun.

These also work better in some descant or triple horns that have a valve in the leadpipe. In these horns getting a snake through the change valve is almost impossible, and the spitballs can often make it through easier.

How to Clean the Leadpipe

No matter whether you’re using an instrument snake or spitballs to clean your leadpipe, the steps are basically the same:

  1. Remove the leadpipe. This will give you a (relatively) convenient way to clean out the gunk. Leaving the slide in will cause you to push the gunk deeper into the horn (and closer to the valves).
  2. Place a towel over the other open section of tubing. Sometimes the gunk can come out with a surprisingly amount of force, and it’s better to keep it contained than letting it fly all across the room (or your horn).
  3. Insert the snake (or spitball) into the mouthpiece receiver. For some horns, you may not be able to fit the snake into the leadpipe. If that’s the case, you can snake from the tuning slide receiver.
  4. Push the snake all the way through the leadpipe. It may take a bit of effort, but if you’re in doubt about how much force to use, don’t be afraid to take it to a repair shop or ask your teacher. You don’t want to put a hole in your leadpipe. If you’re using spitballs, with the other end covered, blow (hard) into the leadpipe.
  5. Remove the snake/spitball from the opposite end. Don’t pull the snake out too fast, remember the other end may still grab some gunk.
  6. Put a couple of drops of oil down the leadpipe to keep the inside surface clean and lubricated.

In addition to the leadpipe, you should also clean out your mouthpiece. You can either use a standard mouthpiece brush, or some standard q-tips. You should run a q-tip or mouthpiece brush through your mouthpiece(s) once every few days. The cleaner the mouthpiece, the less stuff will accumulate in the leadpipe.

A small note if you’re using spitballs on a descant or triple horn with a valve in the leadpipe. While the spitball is “in flight”, make sure that you do not move the leadpipe valve. It can be a tight fit through the valve in the best circumstances, and if you get the spitball stuck halfway in the valve, it can be big pain to remove.

Cleaning the Inside

Even if you do follow all the above maintenance rules (and especially if you don’t), it’s a good idea to give your horn a bath every few months, and a professional cleaning (preferably a chem clean, but ultrasonic is better than nothing) every year or two. Trust me – going much longer than this will lead to some unpleasant discoveries once you do finally clean out your horn!

The procedure for a horn bath is pretty simple – you don’t need much, and you probably already have most of the stuff laying around the house. You’ll need:

  • A bathtub
  • A bath towel (or something similar to lay in the bottom of the tub to set your horn on)
  • Mild dish soap (nothing oxygenated – I use regular blue Dawn)
  • An instrument snake brush and a mouthpiece brush
  • Your regular oils and greases. You can read all about them at the top of the page.
  • A rag (or several) to clean off oil and grease, and a towel (or few) to dry off the horn.

The process is fairly simple – lay the bath towel in the bottom of the tub and start drawing a bath with lukewarm (not hot!) water. Squeeze in a bit of the soap while the tub fills up.

Take apart your horn – remove all the slides and even the valve caps. Go ahead and use the rag to wipe off the legs of the slides to remove any excess grease/oil, and place them all on the towel under water. Make sure you remember where each slide goes (take pictures while disassembling if you’re not sure)!

Once all the slides are out, put the body of the horn in the tub (on the towel) as well. Work the valves at least one time to get the warm, soapy water throughout the instrument. It wouldn’t be the worst idea to put your mouthpiece in the tub as well.

One at a time, pick up a slide, run the snake into each leg, and rinse the slide thoroughly with clean water (not the soapy bath water), and set the cleaned slide on a towel to dry.

Remember, the soap will cut through grease and oil, so while we need it to clean the horn, we don’t want it present when we reassemble the horn. Also, you won’t be able to get the snake all the way through your slides – so don’t try. Run it in as far as it will go and pull it out quickly (but not too hard!). Then, run some clean water through the slide – you’ll wash out (most) of whatever you dislodged.

When all the slides are snaked, rinsed, and set aside, then move on to the body of the horn. Follow the same procedure – snake out the leadpipe and the main tuning slide legs, but don’t put the snake in the valve slide legs. You risk messing up the valves (or getting a bit of snake brush stuck) if you snake these out, so it’s best to not even mess with them. Generally, the inside of the slides (which you already cleaned) will be much dirtier anyway, so it’s usually not worth the risk.

After snaking out all the non-valve tubes, rinse the horn thoroughly inside and out with clean (warm, if possible) water. If you have a hand-held shower head that is easiest, but you can use the bathtub faucet or even a (clean) bucket or big cup in a pinch. Remember, you want to get rid of all the soap since it will cut the grease and oil we use for the slides and valves. Also, spin the horn (carefully) several times to remove excess water, and dry it off with a clean towel.

Once the horn is dry and free of soapy residue, put some Blue Juice (10 drops or so) down each slide leg directly onto the rotor valve. We can do it this way since there should be no grease on the inner slide legs (yet!). This will get some good lubrication on each rotor. After that, you can follow the oiling and the greasing guidelines above on this page.

Final Thoughts

If you have any questions about cleaning or basic maintenance, leave a comment below or feel free to contact me. While there’s no way to do online repair (yet), I’m happy to try to answer any questions you may have.

Also, if this information has helped you, please consider a small donation to help support this site. While I’m happy to offer all this information for free, this site does take time and money to maintain, and I live on caffeine, so a cup of coffee (or two) are greatly appreciated!