Cleaning old bronze

Hulukupu · Post by **Hulukupu** » Wed Feb 11, 2009 6:35 pm

What are good home solutions for cleaning old bronze?

My Mom taught me to clean the copper bottoms of Revereware pots with salt and vinegar.

Is there something simple like this that works for bronze?

Rachel · Post by **Rachel** » Wed Feb 11, 2009 7:05 pm

I've never cleaned bronze (so you might be wondering why I'm responding at all), but I know people who do.

They use lemon juice. I believe the bottoms of the old Revere pots were copper, so I'm sensing an acid commonality.

Rachel

Chris Campbell · Post by **Chris Campbell** » Wed Feb 11, 2009 8:03 pm

This isn't quite what you asked for since it's not in your home for some other reason, but I swear by Nevr Dull. The stuff works like magic, and seems to protect once it's done. And a can of it will last you a mighty long time - the wadding continues to work its magic (more slowly the more you use it) through many uses (so put the used stuff back in the can for later).

Quetzalsailor · Post by **Quetzalsailor** » Thu Feb 12, 2009 9:03 am

Barkeeps Friend works well for us: An antique bronze chandelier; the chromed metal parts of three antique cut glass chandeliers, the stainless steel LeComte stove, Revere cookware, copper cookware, the cheepie brass sink,the stainless sink and washboard, the deeply corroded brass tray, the nickel-plated antique tub faucets and drain parts.

The stuff looks like and is packaged like cleanser but the abrasive is fine enough to not leave scratches. It's definitely acidic and will take a little skin as well as a little metal.

The aforementioned bronze chandelier was partly polished and lacquered bronze and partly nickel plated and lacquered bronze. After removing the remains of the lacquer with thinner, the Barkeeps Friend made short work of the patina on the bronze, but also took the thin plating of nickel off.

Since it's the acid rather than the abrasive that does most of the work, use lots. The acid is quickly neutralized by the metal (and your skin).

Hirilondë · Post by **Hirilondë** » Thu Feb 12, 2009 10:07 am

Greenish, brownish patina is beautiful.

Rachel · Post by **Rachel** » Thu Feb 12, 2009 2:26 pm

I agree, Dave, but he did ask how to clean it ;)

R.

Idon84 · Post by **Idon84** » Thu Feb 12, 2009 3:30 pm

Maybe I should start a new thread but, how do you know when bronze is still good enough to use? Some of my parts are partially pink, some with minor pits but in all look in decent shape.

[img][img]http://i271.photobucket.com/albums/jj14 ... G_0045.jpg[/img][/img]

The bob stay on the left above was replaced because of a nice chip in the hole, the wisker stays on the right are possibly being replaced.

[img][img]http://i271.photobucket.com/albums/jj14 ... G_0044.jpg[/img][/img]

[img][img]http://i271.photobucket.com/albums/jj14 ... G_0009.jpg[/img][/img] This lower pintle(the big one) was fortunate enough to have the zinc attached to it so it still looks great.

Thoughts? If need be I'll get some better pictures today as the above parts have been cleaned since these shots were taken.

Idon84 · Post by **Idon84** » Thu Feb 12, 2009 3:31 pm

BTW... I use vinegar and I like never dull as well!

Hulukupu · Post by **Hulukupu** » Thu Feb 12, 2009 5:57 pm

Mahalo for all the good tips. I like the green patina, too. That's fortunate because oxidation is pretty quick around here.

BTW, Idon84, I believe Tim has a post elsewhere concerning the strength of discolored bronze- I think in the context of replacing his rudder shaft.

meubcr · Post by **meubcr** » Sun Feb 22, 2009 11:54 am

Try this link.

http://www.plasticclassicforum.com/view ... highlight=

The super strong vinegar soak worked well for dark brown patina, but not as well as the acid wash for heavy green.

Tom Javor · Post by **Tom Javor** » Sun Feb 22, 2009 1:20 pm

When restoring the S I had mostly original Herreshoff bronze (circa 1929) that hadn't been cleaned in years. I removed the hardware, manually got all of the old bedding compound and asstd crud off. Ran it through the dishwasher to shake loose the last bits (check the filter screen in bottom of the dishwasher after). Once hardware was as clean as I could get it without chemicals was when the chemistry side of it all began.

Take a decent size bucket, fill with warm water and several cups of bleach -this will be your neutralizing bath. And another with plain water. Then -wearing acid resistant rubber gloves - coat the hardware in question with Lysol Toilet Bowl Cleaner (the version that contans hydrochloric acid). You can either dip or paint on using a cheap NATURAL bristle brush = the throw away white bristed chip brushes are perfect. Allow the bowl cleaner to work for a bit - exact time is dependant on degree of oxidation etc - from 5 minutes to ????.

Rinse the hardware in the plain water bath and then put it into the bleach solution and let it sit for a bit. Change the water in the clean water bath and move pieces into it and let soak. The exact times invovled in the various steps are trial and error depending on the age, condition, alloy involved.

Still wearing the gloves some of the more stubborn pieces can get a 2nd treatment, a light scouring wih a very fine steel wool dipped in bowl cleaner. Repeat the rinses.

Once this is done you will have a clean matte surface piece of bronze - the surface color may take on odd shades depending on the alloy.

Best option at this point is a jeweler's wheel with asstd grits of rouge.
Or a heavy committment of time to hand polishing.

Following this process most any piece of bronze can be brought back to showroom quality.....until the first seagull flies over...

I tried seveal different coatings on the cleaned and polished hardware - none of it lasted to my satisfaction and generally the wear was uneven which led to a speckled look. I finally said- She's an old boat and has old hardware....

David · Post by **David** » Sun Feb 22, 2009 1:52 pm

Bryon,

Just curious why there was a zinc attached to one of your bronze pintels? I would have guessed the zinc would be attached to the stainless prop shaft (assuming it was stainless and not bronze).

David

Idon84 · Post by **Idon84** » Sun Feb 22, 2009 2:20 pm

There were two large zincs on the port side lower pintel and gudgeon as well as a prop zinc (which you can just see).

In the amount of time I've owned the boat, before I pulled it out of the water, it sat infront of my father in-laws home away from other boats. I never really got a good gauge into how fast those zincs were wearing away in that time so really I don't know...? Why you ask? Haven't though about zincs yet or where to put them and I will need a new prop shaft as the new motor mount moves the engine forward about 7".

Here's a pic of the 2 zincs

[img][img]http://i271.photobucket.com/albums/jj14 ... G_0011.jpg[/img][/img]

David · Post by **David** » Sun Feb 22, 2009 5:54 pm

Well, I find it curious. A zinc acts as an anode to protect different kinds of metal underwater that are very close or touching, so a collar zinc on a stainless prop shaft where a bronze prop is attached keeps galvanic corrosion from eating away at the anode (bronze) since it is slightly less noble than stainless. The anode instead is the collar zinc becuase zinc is significatly less noble. We all know this. What I am puzzled about is why install zincs on all bronze rudder gear (I am assuming the pintels and gudgeons are attached with bronze fasteners). There is no reason to "protect" bronze from itself. It is not even necessary to protect dissimmilar metal that is not in close proximity underwater (unless of course both types of metal are bonded together..in which case you essentially have a battery and it needs a sacrificial anode). Perhaps there was a stray current corrosion issue where the boat was kept and the zincs were added as some sort of precaution for that reason.

Just curious. (Maybe it's like the case of the upside down ports)....

David

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Cleaning old bronze

Cleaning old bronze

Thanks

worked for me..........