Chemical Cleaning

[Himes]

I have a friend who is a repair technician. He once told me that chemical cleaning should only be done if the horn is in reeeeaally bad shape (not regularly) as it scours the inside of the instrument or something like that. Is there anything to this? I have read old posts and lots of people have discussed chem cleanings, but I am trying to discern what he was talking about (he's not a tuba specialist, but he does usually know what he's talking about with repair...)

Any of you techs have insights?

Thanks,

Himes

[basstbone64]

As a tech who is not an expert (I've only been doing this about four years), I would disagree. There is no material being removed from the horn and regular (yearly or every two years) Brite-dip'ings are only beneficial for protecting against red rot.

I suppose if a tech were to leave the horn in an acid bath (Etch-clenz, for example) for an abnormally long time, that could, theoretically, do some harm--likewise with the Brite-dip.

I don't know much about the ultra-sonic cleaners, but I was under the impression that they were even more gentle about the cleaning.

Hope that helps.

[Dan Schultz]

I do not routinely perform chem-cleanings unless I actually see mineral deposits like lime, scale, and brass oxides (greenish corrosion) present. After chemical cleaning, the brass is left with a light reddish film that washes away during the rinsing process. I think this reddish film is actually solid copper where the zinc has been washed out of the brass. It doesn't amount to much, but I'm certain there is some material, although minute, that is lost in the process. I'm a firm believer that the dark oxide that forms inside the piston casing is beneficial to good piston action. Removing it with chemicals forces one to start the 'seasoning' process all over again.... as if the horn is new. Seems to me that chem-cleaning is more-or-less a 'profit center' for most repair shops that service student instruments and schools. In reality, you can get rid of all the 'nasty stuff' with a mild detergent and a cleaning snake.

[Rick F]

FWIW...

I took in my horn in last month to get a chem cleaning. The tech looked it over (pulled some slides and valves and looked them over) then said, "It's not like me to turn away business, but I don't think you need it. From the looks of it, you've been keeping your horn pretty clean". It had been 2 years since last chem cleaning. I do clean it out in my tub at home every few months.

[Lee Stofer]

Chemical cleaning is a wide-open subject. Instruments themselves vary greatly in metallurgy and in craftsmanship, cleaning processes can vary greatly from shop-to-shop, and players' chemistry and frequency of use of their instrument vary greatly.

I had a euphonium player bring me his Besson today, and, using his 4th piston, I demonstrated what my process entails. After I had cleaned it, he told me that his instrument had been "chem-cleaned within the last two months (with what - Dr. Pepper?!!!), and the valve I had just cleaned had not appeared as clean as this, even when it was new.

My experience is that the vast majority of instruments out there get significant lime-calcium build-ups, and the least invasive way to remove that is with a de-limer/de-scaler. That can leave reddish deposits on the metal, which is copper that has started to adhere to the brass part. Much of that can be removed when the piece is soap-and-water scrubbed and rinsed, but a brief dipping in bright dip will remove virtually any discoloration in the surface of the metal. I find that this makes slides work like new, and the valves work very, very well. That said, the bright dip does perform a microscopic etching of the brass surface, and this should not be performed often, maybe once every 5 or 6 years at most. If a shop does the de-limer/de-scaler solution only, then the valves and slides would be clean and would work well for a while, but would need attention and repairs more often.

The best way to tell if your instrument needs a chemical-cleaning is to remove the valves and slides,let them dry, then inspect them. If a whitish haze appears on your valves and slides, they need cleaning, and soap and water alone will not remove those deposits. If the instrument has had the full treatment, ie., soap-and-water scrubbing, de-lime solution, rinsing, bright dip, then re-washing and re-rinsing, drying, and thorough lubrication, it should only need a soap-and-water bath for the next 5 years or so. When treated as described above, the instrument should stay cleaner and require less maintenance.