What will take oxidation off brass without a lot of elbow grease?

Is there anything that comes in a brush-on or at least spread-on form that will take spots of oxidization/red rot crud off brass without eating the brass itself and does most of the work for you, sort the way Tarn-X works on silver? I'm giving an old trumpet a going over and want to reduce some of the tedium in resurrecting the sheen of the metal before lacquering it.

Also, what sort of surface preparation is recommended before lacquering? Please no "take it to a repair shop" answers, the whole point is to be a DIY project.

Thanks for all shared wisdom.

Reply to
Doc
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Reply to
Dave Stephens

Sailors have been cleaning brass in the US Navy for many years with vinegar and salt. It works very well. I also recommend Brasso, which does require a bit of labor, but it works well too.

However, it has to be really really clean before lacquering, so if you use something like Brasso then you will need to clean it perhaps with acetone to remove all residues.

GWE

Reply to
Grant Erwin

No - Pink spots on brass are the brass dezincifying to leave copper behind. You have to shift these mechanically with something abrasive, so as to cut through the dezincified layer. This can leave sizable "ulcers" behind. I don't know of any way to replace the zinc chemically.

As it's presumably a trumpet, I'd be very wary of going overboard with abrasives. Better pinkish spots thatn divots. A light job with a fine Garryflex, 3M abrasive pad, or even Brasso is about the limit.

Don't use salt and vinegar. It's a powerful cleaner, but the corrosion problems afterwards aren't worth the trouble,

Reply to
Andy Dingley

Tarn-X isn't made for brass, but was looking for something that basically does the same thing, knocks down most of the oxidation by itself without having to scrub. Besides the labor factor, there are some pits that are going to have to be gotten into chemically, hitting them with any kind of a cloth/polish or wet/dry paper just goes over the top of the pits. Plus, I really don't want to totally disassemble the horn to get every surface, if I can avoid it.

Reply to
Doc

They advertise some kind of soap/detergent/cleaner on TV right now. (saw the add during the last couple of days) In the ad, they put a dirty penny half into the goop, and it comes out clean and shiny (no scrubbing) watch for that ad, and get that goop. I have a horn I need to clean the same way, but mine is an old antique Conn with engraving on it. An expert told me to be careful of cleaning it. If I buff it off, (she said) the engraving might come off with it, and then the horn would be worth much less. So I need to do the same thing. But I have to first get the old lacquer off, and this probably means using paint remover or some such real strong stuff......

Reply to
William Graham

Ok, if the red rot is on the leadpipe you might as well replace it.. just the leadpipe that is. Most often you will find the inside is eaten away before the outside. Red rot is caused by your Brass turning back into Copper. Saying that, you can see it can't be polished away. All you are doing is polishing the copper not removing it, most of the time it runs all the way through. Live with it if it isn't leaking yet and put a patch on it if it is. If you are DETERMINED to polish this, try brasso and wash the instrument with alcohol before lacquering. BTW.. get a Ferrees catalogue and they will sell you a really nice clear lacquer, they are on the web.

LLB (horn builder)

Reply to
brassbend

Are you quite sure you want to lacquer it? I know a number of trumpet players who have de-lacquered their horns (the better off ones then silver-plate, but the rest claim that simply getting the lacquer off makes for better sound, while the silver is an appearance thing only).

I looked into having a trombone stripped and plated, and it was about as much as a new trombone...and probably makes less difference than with a trumpet (lower pitches).

Reply to
Ecnerwal

I wonder how a large vibratory tumbler with ground corncob & brasso would work. Of course you'd need access to such a machine. Use for deburring parts.

Or,, a muslin wheel & tripoli compound, on the exterior surfaces a big wheel would cover alot of ground , and a dremel in the tight spots.

Tony

Reply to
Tony

Sailors have been cleaning brass in the US Navy for many years with vinegar and salt. It works very well. I also recommend Brasso, which does require a bit of labor, but it works well too.

To the list:

I was a sailor, never used vinegar and salt though. First cutter I was on everyone used Brasso. Second one was a Nevr Dull ship. I like the Nevr Dull a little better. It is a cotton waste impregnated with corrosion eating gook and leaves an oily film that protects the brass a bit from salt. Both Brasso and Nevr Dull will erode brass, especially fine details like engraving.

I use Nevr Dull on my horns, but not often. Mainly I use a polishing cloth from the instrument shop.

good luck

jn

Reply to
thursday

Is the salt strictly there as an abrasive or does it have some effect chemically?

Reply to
Doc

The problem is getting into the little pitted spots. Even a dremel isn't going to do the job. I need something that will do the cleaning chemically.

Reply to
Doc

Both. It's quite a powerful cleaner, but you have to make sure it's well neutralised afterwards or you'll see copper chlorides appearing (pale green, sometimes looks a bit like mouldy fruit).

_Never_ use salt and vinegar on cuprous alloys that are either even slightly porous (most castings) or valuable bronzes. The risk then is that you set off "bronze disease", a self-perpetuating form of chloride corrosion. Once this starts it's a real pig to stop it (and the chemistry to do so is a little hard to find and toxic).

Never trust the military's advice on cleaning things. They have unlimited pools of labour and many approved techniques are there as a deliberate make-work policy. Lots of these techniques work fine, but only if they're re-done daily. Most civilians want something that gets clean, then stays that way.

Reply to
Andy Dingley

But even tap water contains some chlorine, so I doubt if using salt and vinegar on a horn would cause any harm, provided you wash it off well when you are done. As a matter of fact, it goes without saying that no matter what you use, you should wash the horn well when you are finished.

Reply to
William Graham

Ouch on the abrasive pad. Unless you plan on making a matte finish imitation of one of Dave Monette's instruments. (Great businessman - instead of laborious buffing, just rough everything up with a scotch brite pad and change 10 times as much for the results).

That major reason for taking the instrument for professional chemical cleaning, degreasing, and laquering is not that you can't get your hands on the chemicals, but that it's silly to do so and then have to dispose of total-immersion quanitites for a single use... in the shop it sits there and gets used over and over and over again.

Reply to
cs_posting

I got a really cool polish rag from UMI. Not a major fan of UMI but they made a pretty nice chemically treated cloth. I use it on my horn and ANYTHING silver around the house. Works great and it's very easy to use.

Jon Trimble

Reply to
Trumpet Newsgroups

You can't clean away the little pitted spots because it isn't contamination, but missing zinc that is the problem.

For just general work in close quarters around the braces, you "rag" with cotton tape, or for small detals, flat shoelaces.

A novice trying to buff a trumpet is likely to have it caught by the wheel and flung across the room and smashed... there's just too many things that can snag.

Reply to
cs_posting

Yes....The way to prevent this is to use a very low power tool. One tool that I like for this purpose is a draftsman's automatic eraser. These are getting pretty scarce, because most draftsmen today use computers, and no longer draw on paper taped to a drafting board. But if you find one of these things, pick it up, because it can be a very useful tool. It had three "fingers" that wrapped around a long eraser tube that might be 5 or 6 inches long. As the eraser was used up, you could spread the fingers and feed it more eraser. When you turned it on, it spun the eraser around at fairly low RPM, so you could press it against your pencil drawing and erase a part of it. You can make it's fingers grip a pad of cloth, or felt, or steel wool, and use it to polish or burnish, or grind away at something valuable such as jewelry or wood, or a trumpet without worrying about it being flung across the room and destroyed, and yet, it would do the job a lot easier than pure elbow grease......

Reply to
William Graham

no, it's not made for brass. but; i sure don't recomend it for silverplate either. i'm not sure how it works on 100% silver; but- don't try tarn-x on silverplated instruments. also- it's my experience that any raw brass will tarnish quickly- no matter how well polished; unless it is laquered. live and learn; i always say...

Reply to
JoeGuy

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