Horn Maintenance and Thoughts on Ultrasonic cleaning
By Jim Langenberg, Owner, Brazen Bandworks
For several years now I’ve been working as both a professional brass player as well as an instrument repair technician. I had learned some things about maintenance from my lesson teachers, but to be honest, most of the information was incomplete and generally only came up when something wasn’t working. Looking back now as a brass repair technician, I am surprised I didn’t hear more about it. Our instruments are fairly expensive, yet many of us think of changing the oil in our car long before doing anything to our horns.
Let’s talk about what goes inside our instruments for a minute. We play instruments built of metal that we blow into with our mouths. As much as we may try to tell our woodwind and string friends that our instruments produce “condensation,” we all know some saliva comes out when we buzz. That saliva can be hazardous to your horn: your body’s acidity levels, oral cleanliness, and general health all contribute to the internal picture of your instrument. Yes, the condensation being produced from our exhalation is not devoid of moisture, microscopic organic particles, and other bacteria. A good way to explain this to a student is point out how we can see our breath in the winter when the humidity level is at 0%.
Ok, so I blow stuff in my horn… so what?
Well… all this stuff we blow in the horn is the problem. It collects in the valves, slides, rotors, and most of all, the mouthpipe. These locations are where many of our interior maintenance issues occur. Our saliva is generally mildly acidic or neutral ph. Even if you have neutral body chemistry, the microorganisms in your saliva will break down the other organic materials and that will result in acid in your horn. This acid is the enemy. It eats away at the metal through corrosion. Corrosive buildup is also what causes rotors to hang up and slides to get stuck.
So… what am I supposed to do?
Well, I’m sure we’ve all been told to get a snake to swab out our mouthpipes. Yes, that’s a good idea. It will get some of the bad stuff out. How often? Once a month is an easy interval to remember, but this varies based on personal body chemistry, how clean your mouth is when you play (did you just eat? Are you drinking coffee?), and how pitted the metal on the inside of your instrument currently is. Pitting is a term used for the craters or low spots that develop, especially in the mouthpipe, where corrosion has eaten away at the metal. The pits have a tendency to hold on to the moisture and other particles going through our instrument which in turn causes corrosion to occur more quickly. So, if you are getting a lot of stuff out of your horn each time it is swabbed out, step up your frequency and evaluate if you need to be brushing your teeth or at least rinsing your mouth before playing. To take this a step further, try using some Dawn Liquid Dish Soap (the blue stuff) on your swab and rinse thoroughly. I recommend against getting soap anywhere else in the instrument unless it is being fully disassembled including the entire rotor assembly. The soap will cause problems with your valves unless it is completely removed.
Past swabbing, the best thing you can do to try to keep corrosion to a minimum is thorough oil and grease application. Keep your slides well-greased with the thickest product you are comfortable using, same with your rotors and bearing surfaces. Of course, it’s unnecessary to go so thick that your valves are slow or it is too difficult to pull your slides in time to make that next entrance. The benefit of thick oil or grease is it will last longer and protect better until the next application. One shop I worked at would actually put some oil in the mouthpipes after being play tested to try to keep any corrosion from showing up in the new instruments. No one wants to buy a new horn that is dirty. I recommend oiling piston valves daily, rotary valves every week, and slides once a month. More often is even better. I recommend trying to stick with the same brand of oil to keep thing from gumming up. Not all oils play well together.
Ok,
so, I looked in my horn and it was dirty, so I swabbed it out and now I see this
white and green stuff in the slides… now what do I do?
Now it’s time to go see a professional. Unless you yourself are a brass repair technician, do not try this at home. Professional cleanings should involve an acid dip. Acid causes corrosion, but acid is also how corrosion gets removed. Horns should be completely disassembled including removing the rotors and bearing plates as well as all moving parts before being dipped. Ultrasonic machines are also filled with acid so whether your preferred shop uses just a chemical dip or an ultrasonic machine, the same result will be obtained. Any quality shop will scrub out the interior of the instrument and neutralize the acid with soap and water before reassembly and oiling. In order to keep your instrument in top shape you should invest in a professional cleaning once a year. Again, depending on your personal habits and body chemistry you may need to go more often. Interestingly enough, if you play your instrument for several hours every day you may be able to go longer between cleanings as the constant movement of fluids in the instrument seems to slow the growth of corrosion. On the flip side, I have seen student horns that are not played often enough get rather corroded very quickly because of what is happening while the instrument sits between playings.
Do I need to worry about the outside of my instrument?
I recommend wiping hand oils and sweat off the instrument with a clean microfiber cloth. Like other body fluids, sweat can be acidic. Just like the inside of the instrument, the acid can wear away some metal and cause corrosion. I’m aware that many players like the patina they develop on their instrument. Most shops require a polish as part of their cleanings. This is often done because after the corrosion is removed there is often a pinkish color left behind. That pink is not red rot, it’s copper that was left behind when the corrosion was removed. It can be polished away so it looks like normal brass again, or it will darken in time. If you prefer to have the patina left alone, most shops will agree to not polish. As a note, the patina will be lighter when you get the instrument back because the dirt will have been removed. The color will come back.
So, your title says something about the dangers of ultrasonic cleanings, should I be worried about them?
I use ultrasonic cleaning machines frequently and they can be very helpful with speeding up the cleaning process for a repair technician. I have also learned that cleaning an older instrument ultrasonically can cause damage because the metal has thinned by corrosion and general wear, and similarly for instruments already affected by “red rot.” If you have a new or fairly new instrument, you will be fine.
Hey, I’ve heard that term before, what’s red rot?
Red rot is a term that refers to the pink or reddish dots that can occur on an instrument. This is a specific issue with brass tubing. Brass is an alloy of primarily two metals, copper and zinc. Copper is more resistant to corrosion, but zinc tends to be very vulnerable to being eaten away by corrosion. You can’t predict if and where you will have an issue with red rot. As much as manufacturers try, zinc does not get completely and uniformly mixed with the copper. There will be small pockets of zinc in the brass. If the pocket is large enough it can go all the way through the tube. Often, when you see these red dots you will see a little white or green dot in the middle. That’s where the corrosion is eating through the metal and can eventually form a hole. This is often from a lack of maintenance. Unfortunately, even with good maintenance it can still occur. A very prominent manufacturer once told me they expect a yellow brass mouthpipe to last 10 years on average. Having corrosion removed is the only way to slow the red rot process. Sometimes it is too late and it will be necessary to replace the tube.
Ok, so what’s the deal with red rot and ultrasonics?
Ultrasonic cleaning machines work by shooting high intensity frequencies into the acid bath to vibrate the dirt loose. As was mentioned above, having red rot does not guarantee the instrument has a hole. The trouble is, in my experience, the frequencies and vibrations from the ultrasonics often causes the red rot to open up more often than when an instrument is cleaned with acid alone. A coworker once showed me what happens when you put a piece of tin foil in an ultrasonic machine. When the cycle had completed, the tin foil was full of tiny pin holes. Now, if your instrument is in good shape, this is not an issue as instrument tubing is much thicker than tin foil. Because of this, my shop (www.brazenbandworks.com) only uses a small ultrasonic machine for cleaning solid parts. To be clear, I have full confidence in the ability of ultrasonic machines for cleanings, but my personal preference is to err on the side of caution and not use them on old horns or horns with any evidence of red rot.
In conclusion
The recipe for a happy horn includes:
- Keep your mouthpipe clean by keeping what goes in the horn clean as well as regularly swabbing out the leadpipe.
- Keep slides, rotors, and bearing surfaces well lubricated.
- Plan an annual professional servicing of your instrument to remove corrosion and make sure everything is functioning properly.
