Red rot

[pjv]

To my utter disappointment I discovered red rot (and a lot!) on my Olds Flügelbone. From just past the mpc receiver all the way into the adjoining bow.
I rarely have any use for it but when I do it’s magic.

So I did what seemed right (this this post).
I flushed out the infected areas with crystal soda and rinsed it out.
Then I but in some natural vinegar, let it sit for a while, then scrubbed it in with a trombone snake.
I then rinsed this out thoroughly, afterwards drying it with one of those mattress air compressors.
I twisted open the other end of the snake, replaced the small brushes with a piece of lint free cloth. Swabbed the cloth up with lots of slide grease and went to work on the infected areas.

Long story. Question is, is this the way to go? Will this layer of grease provide a lasting protection for the metal?
Thanks

[Tim Jackson]

It's been so long... I have an old Getzen flugabone and I love it! I switched over to my King as it was more even and in tune. But the Getzen has "the magic" a very pleasing and fun instrument to get around on. The lead pipe developed spots and on to rot. I had the lead pipe replaced. I like the flugabone vs the bass trumpet for two reasons. the flugabone is conical and easier to use mutes - like the cup/plumbers helper!
No case, I just throw it in a shopping bag with a couple of mutes. Great gigging horn for jazz.

Hope your fix extends the life as my lead pipe was too far along to save.

Tim

[bloke]

Vincent Bach bought that tooling in the 1980's. When production was discontinued, Allied Supply (Elkhorn, WI) bought all of the remaining parts - decades ago - and still has some mouthpipe tubes (part # S800) in stock. (Usually, instruments with "red-rot" suffer that problem at the mouthpipe tube, if anywhere.)
Allied (the Getzen people) only sells to businesses and repair shops, so (if you want to replace that part) you'll need to get someone else to buy it for you.

Your soda (if anything like baking soda...??) is alkaline, and probably (??) didn't do much good.
Cleaning vinegar (more acidic than food-grade vinegar) is cheaper (at least, in the USA) than food-grade vinegar, and will slowly dissolve lime deposits. Lime deposits are what promote dezinctification.

If all the lime is dissolved away from the inside (so that the bore is reasonably smooth and not distorted with lime) there's no need to replace rotten parts until they actually end up with holes in them. Prior to patching or replacing, small holes can be be easily covered up with the extra-thick/extra-hard type of clear fingernail polish.

[Stryk]

Before I joined this forum, I had never heard of red rot. I would have to assume the major contributor is acidic saliva. However, I now may want to rethink my second cup of coffee I drink as I practice most mornings. That would suck not to be able to have my coffee then! Could a contributing factor be the alloy itself? Does it happen more often in specific brands?

[bloke]

Acid does a good job of cleaning copper and copper alloys, but doesn't really rot alloys.
Obviously, some type of super-low-pH acid might "eat" most anything (as in sci-fi movies), but mild acids tend to (mostly) just remove oxidation and VERY slowly dissolve the base metal of copper and copper alloys.

High-zinc (more than 20% zinc) brass is the most susceptible to rot, because bases (high pH) tend to dissolve the zinc in the brass.

It should be noted that I'm only speaking from experience, and not from legitimate scientific knowledge...so I'm perfectly willing to be corrected.

[hrender]

I have lately become interested in this also given some potential issues with my horns.

Good description of dezincification here: https://www.canada.ca/en/conservation-i ... brass.html

I'm still reading it so haven't gotten to the conclusions yet.

More detail on the science here: https://www.sciencedirect.com/topics/en ... cification

[iiipopes]

Acid does a good job of cleaning copper and copper alloys, but doesn't really rot alloys.
Obviously, some type of super-low-pH acid might "eat" most anything (as in sci-fi movies), but mild acids tend to (mostly) just remove oxidation and VERY slowly dissolve the base metal of copper and copper alloys.

High-zinc (more than 20% zinc) brass is the most susceptible to rot, because bases (high pH) tend to dissolve the zinc in the brass.

It should be noted that I'm only speaking from experience, and not from legitimate scientific knowledge...so I'm perfectly willing to be corrected.

This. ^ Red rot is more an electrolytic reaction than it is a corrosive reaction, which explains why the alkaline treatment doesn't help, and why lime deposits are a cause. Or the more fancy-schmancy kolig (to use bloke's colloquialism) paper:
https://www.sciencedirect.com/topics/ch ... cification

"Factors which cause increased rates of dezincification are high temperature, high chloride content of water, and low water speed. Dezincification is also likely to occur preferentially beneath deposits of sand or silt on the metal surface, or in crevices where there is a low degree of aeration."

Crevices and lime deposits: this absolutely explains the condition of a baritone I had for a short while some years ago: where the receiver was soldered onto the lead pipe was completely rotted through with holes, only reparable by replacement, and even though the rest of the horn was in good shape. I didn't want to spend the money, so I donated it and bought another.

Lesson learned: keep the horn clean, dry, and free from deposits of all kinds.

[hrender]

Actually, duh, it wasn't that long. Sorry. Key bit is here.

Preventing dezincification

Other elements can be added in brass with higher zinc concentrations to make the brass more resistant to dezincification. Ancient brass alloys, which generally contain tin or impurity elements, resist dezincification better than modern brass alloys that contain only copper and zinc (Scott 2002). Modern tin brass has about 0.5 to 1 wt% tin added to the copper-zinc alloy; such alloys are significantly more resistant to dezincification than the same alloys without tin (Selwyn 2004). When this amount of tin is added to cartridge brass, the resulting alloy is called admiralty brass. Further protection against dezincification is obtained if smaller amounts of arsenic, antimony or phosphorus, in the range of 0.02 to 0.1 wt%, are added to tin brass. Today's admiralty brass generally contains one of these three elements in addition to tin.

Brass should be kept clean and dust free. It should be handled with gloves to avoid contact with salts and acids in perspiration. Brass in public spaces should be cleaned regularly. If possible, commercial polishes should be avoided. Some of these contain acids to speed up cleaning; others contain ammonia to remove dirt and grease. Both acids and alkaline solutions can cause dezincification. An abrasive slurry could be prepared instead, based on precipitated calcium carbonate or other harder abrasives. For detailed preparation instructions, consult CCI Note 9/11 How to Make and Use a Precipitated Calcium Carbonate Silver Polish.

Whenever brass is cleaned, it should be rinsed well so that any residues from cleaning are removed. Residues of commercial polish left on copper alloys may react with the copper to produce green-blue compounds. Citric acid, for example, is found in some polishes and will produce green copper citrate. Even non-reactive residues will be noticeable if they accumulate in crevices.

Polished brass is often coated (for example, with a clear lacquer or wax) to protect the shiny surface from tarnishing. Such a coating will also minimize dezincification, as long as the layer remains adherent and undamaged. The disadvantage of a coating is that it has a finite lifetime and requires regular maintenance or removal and replacement. For questions about coatings, a conservator should be consulted. For further discussion on the care of historical brass and bronze, consult Deck (2016) and Harris (2006).

For what it's worth, Bon Ami has calcium carbonate as one of its primary ingredients, but it's abrasive.

DIY video:

[bloke]

I still believe that sloshing oil (no thicker than the oil used on pistons or rotors) around inside the valveset of a brass instrument discourages lime from adhering to interior surfaces. Again, this isn't from any textbook, but from experience. I believe that people who seek out valve oils that are "long lasting" (and who use as little as possible, because they are paying as much as $4/oz.) are missing one of the benefits of (me: every time I play) oiling.

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[hrender]

From reading the article quoted above, it sounds like any non-reactive coating will help once the instrument is clean. Lacquer or wax on the outside plus oil or grease on the inside should do the trick.

Did some more reading, conclusions are about the same:

Deck, C. The Care and Preservation of Historical Brass and Bronze (PDF format). Dearborn, MI: Benson Ford Research Center, 2016.

[pjv]

Your soda (if anything like baking soda...??) is alkaline, and probably (??) didn't do much good.
Cleaning vinegar (more acidic than food-grade vinegar) is cheaper (at least, in the USA) than food-grade vinegar, and will slowly dissolve lime deposits. Lime deposits are what promote dezinctification.

The soda (cleaning soda, soda crystals, sodium carbonate decahydrate) are more alkaline than baking soda (bicarbonate of soda, sodium bicarbonate) and I used it just to clean the pipes.

The cheaper but more concentrated cleaning vinegar I avoided assuming that, even when diluted with water water (common with cleaning) it'd be too aggressive. Is this a wrong assumption?

Also, how will I know that all the lime deposits are dissolved? I can't see doodly squat down in the tubes, even if I try shinning a light down there.

[pjv]

I still believe that sloshing oil (no thicker than the oil used on pistons or rotors) around inside the valveset of a brass instrument discourages lime from adhering to interior surfaces.

As you so kindly noted on a previous post of mine. Sloshing lamp oil around. (I still don'y know where I should dump it out afterwards. Most venues aren't set-up depositing chemicals)
The reason I greased this up (instead of using just valve oil) is because the valve set is way farther down the instrument and the red rot part. I figured since instrument sits more often in the case than on stage that this was a wise decision.

Or am I making a judgement error?

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[bloke]

> Where is it rotting...??

> Is the mouthpipe tube rot-free, yet rotting is occurring further down the instrument?
(not impossible, but somewhat of an anomaly, particularly when mouthpipe tubes are fabricated of regular yellow brass - as are those)

> How about some close-up pictures of some places that (you suspect) are red-rotting; is there any chance of misdiagnosis?
(The picture is showing up as fairly low-resolution to me).

>* "depositing chemicals"... ...Seriously...? two or three tablespoons of of lamp oil - that could be soaked up into a paper towel and tossed in the trash (or burned up, in a few seconds with almost no vapor - even if done indoors)...
Are things ACTUALLY that bad in Europe, now?

> My cleaning acid (formulated for this specific purpose) is considerably stronger than "cleaning vinegar" (yet still only stings my skin where there is a scrape or cut). Once or twice (some emergency, etc.), I have forgotten to remove instruments and have left them in there for thirty or more minutes...' no harm. It WILL tend to loosen old nitrocellulose lacquer (and occasionally epoxy lacquer) which is so old that it has lost its adhesion (my slang for this: "dead lacquer") or has been severely stressed (dent removal in specific areas)...but (usually) only when left in the acid longer than I usually leave an instrument immersed (ex: c. 15 - 20 minutes, when some particular instrument's interior is REALLY badly coated with hard lime).

I'm trying to help...even if my questions make seem to be judgemental...I'm trying to not be, yet I am me.


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[pjv]

As I mentioned at the beginning of this post; it starts from just past the mpc receiver and continues into the adjoining bow. I'll take pictures tomorrow when I'm back at my practice space. (Yeah, it's been a great two years for practicing).

"depositing chemicals", is my failed attempt at light humor; but two tablespoons is a lot of oil to dump on the floor when I forget to bring a towel (something I never used to do for my water-key disposals, but have been doing since Covid...if only to make people feel more comfortable).

Glad to know that cleaning vinegar is not too heavy for brass instruments. So it's OK to leave un-diluted (1:1) cleaning vinegar in the horn over night? Will it do the trick (since I will NOT be using any kind of acid)?

Assuming it is red rot, how can I tell if I've succeeded in dissolving the lime deposits?

Judgemental? Nah. I'm the one asking for help. How the helps packaged is how it's packaged.
But please, be judgemental. I might learn something.

I pulled out the mts, plugged up the horn with my thumb and blew in hard. No leakage. It's worth stopping the rot.

[bloke]

If your mouthpipe is the main thing that is rotting…and it’s really bad, you can buy that part perfect/new, as previously pointed out.

If it’s minor, I would probably (quoting Dale Phelps) say “pfft”.
Plug up the low end of the mouthpipe, set the instrument on the bell, fill it up with cleaning vinegar from the receiver, and let it go until the fizzing stops. For good measure, maybe you could put some fresh vinegar in there after that and see what happens. If you have a cleaning snake brush, it’s then time to run that through there - maybe with some hot tap water…(??)

[pjv]

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[bloke]

If you believe that you’re going to be owning that instrument for the rest of your life - and using it more than just once a year or so, why not buy one of those mouthpipe tubes and stick it in the back of your sock drawer (for the future)?

[pjv]

I’ve already been considering this.
I need to make 100% sure that I know which Olds Flügelbone I have.
I seem to remember reading that they were made with a .509” bore, and later on in another bird size. I believe this one’s a .509” but of course I need to be sure.
And then t eed to be sure that the one I’m ordering it from k owe what they are doing.
Down side is I haven’t been impressed with Dutch brass workmanship as a whole. This isn’t encouraging.

[bloke]

I only know of one...and the only parts I know of that aren't interchangeable are (probably) the pistons, because Bach INTENTIONALLY added a couple thousandths of an inch to the various Olds (marching instruments, "concert" tuba, and "concert" baritone horn) piston diameters, so that their pistons (which Bach intentionally changed to be proprietary to Bach) would not be purchased by repair shops to repair (and - thus - sustain/keep in circulation) Olds/Reynolds instruments.