Removing nickel plating from brass
Is there any easy way to remove nickel plating from brass, that could be done safely at home?
Thanks in advance for any suggestions.
Have you safely tried muriatic acid?
Chemicals like that are hard to get hold of in the UK.
That's interesting. Around here muriatic acid is used to control the pH in swimming pools and so is very available and cheap. Unfortunately muriatic acid would be a very poor choice for what you want to do. It won't attack the nickel but will attack the zinc in the brass very quickly. Remember Ni is a noble metal, its in the Ni, Pd, Pt column of the periodic table, not much attacks those metals.
Originally Posted by Webley91
Nickel strips easily. It is nowhere as resistant as platinum, etc. and readily forms chlorides, sulfates and nitrates. Unfortunately, the solution will also attack the brass. I have often stripped nickel from copper and brass. A thin layer will come off quickly in dilute hydrochloric acid. A common methode of stripping thicker layers is a solution of 3 parts sulfuric acid to 2 parts water by volume. Apply a positive DC voltage to the part and use a lead cathode. About 6 volts should work. The solution can be at room temperature, but have good ventilation or work outside because it will generate gases. I do it in a fume hood. Adding water will speed the process, but it will also increase pitting of the brass. Adding 30 grams/liter of copper sulfate or glycerine will reduce pitting.
There are other methods, but all involve an acid such as sulfuric, hydrochloric, or nitric. Even worse, are the cyanide solutions. Unless you are an accomplished chemist, stay away from cyanides. They are actually not that poisonous by themselves, but mixing an acid, even something as mild as lemon juice, with them can generate hydrocyanic acid, which is deadly, used in gas chambers.
If you want to explore this further, I can email you scans from the Metal Finishing Guidebook. Since they are copywrited, I don't want to put them on a public site.
Last edited by 9100; 02-21-2009 at 05:51 PM.
Reason: Just grammar
Removing plating is called stripping in the trade, so that is the key word for a web search. For instance, there is this site which claims to sell what you need:
Back in the 1950's, there was a local one-man plating shop that could strip nickel from brass, then polish and lacquer the part for a low price. That was well before the concept of hazardous waste made small low-tech plating shops disappear. I suppose he used an electrical process, kind of the reverse of plating. The brass was not damaged in the process. Aladdin and Rayo oil lamps were made of brass and were all originally nickel plated. For some reason, people, my parents included, wanted them to be polished brass. I still have two polished brass lamps that the local plater stripped and refinished and converted to electricity fifty years ago. And I have found two more with very nice original nickel plate.
By the way, muriatic acid is also called hydrochloric acid (HCl). It is often used to wash excess mortar off new masonry work, so building supply stores carry it. The fumes are nasty and cause instant rust on bare steel. But I have used it to remove zinc plating from steel screws so they look more period in antiques. It is tough to find bare steel screws anymore.
This will do it but will not ship outside conus:
Have not checked MSDS to see exactly what it may be, but they say it gives off strong ammonia odor but safe for copper alloys.
I learned as a child that household (dilute) ammonia will instantly brighten a copper alloy penny, then go on to dissolve the coin. I never tried the ammonia on nickel plate.
Originally Posted by singleshot
Seems like everything is hard to get in the U.K.. Can't have a pocket knife,fly old aircraft anymore,can't fly but lightweight models. Can't have guns.Time for the people to rise up,or they will legislate away your machine tools,lest you make a weapon with them!!!
They'll give every idiot and his dog the keys to a 2 ton lethal weapon with a wheel at each corner though, even if they can't drive for toffee.
Not really. They're often available to the public in various forms based on particular uses. So:
Originally Posted by Webley91
Hydrochloric Acid — This can be bought under the name of "Spirit of Salts" from any decent plumber's merchants. It's used for drain clearing, descaling and suchlike. The bottles I have carry the "Blanchards" tradename and come as a 32% concentration.
Sulphuric Acid — This can be bought as "Battery Acid" from various sources — here, for instance:
Remember that battery acid is typically about 1/2 water, so it is on the low concentration side for nickel stripping. It should still work, but would require more attention since pitting would be quicker.
Gwilson, I haven't heard about a pocket knife ban in the UK. I carry a Swiss army knife at all times and use it constantly. I rarely (never) get in knife fights, and won't I if possibly can avoid one. I have used my 1911A1 seriously once, to stop a mugging outside my shop. Two kids, whose combined ages did not add up to mine, were beating up an older man, had knocked him down and kicking him. A .45 barrel is a great behavior modifier, and my only regret was that I didn't have my shotgun for the larger bore looking at them. I am also eternally grateful that I didn't have to shoot one of them, but I feel that I acted properly because the alternative is to turn the streets over to the criminals. People say that we should let the police handle it, but they were not there and the event would have been over before they came. BTW, the Webster Groves, MO police were completely unconcerned about my having the gun. At least they know which side they are on. This is a side of firearms ownership that doesn't get a fair hearing.
Thanks for all the suggestions everyone, I might give one of them a go.
9100: It would be great in the UK if we had the right to use firearms against criminals, but in the UK, if you fight back against an attacker, usually it is you who will find youself on the wrong side of the law. The criminal will get a pathertic "punishment" from the courts and be sent on their way, only to do it again tomorrow. I would like to see what the average scumbag kid with a kitchen knife or boxcutter trying to steal your wallet would do when looking down the barrel of a Colt 1911.
I know a sure fire way to get the nickle plate off brass based on a recent experience.
My dear wife decided my bathroom toilet needed to have some bleach added to the water in an attempt to remove some slight rust stains. Wish she had asked or told me first.
I came in the house opened the lid and took a wiz wondering why my pee turned green in the pot. In the time it took to hit the flush the nickle plated hinges were already peeling.
Sure glad the room was ventilated enough that I didn't get a whiff. I can now say with authority that Chlorine gas will really remove nickle plate. Also that the Clorox stays in the laundry room where it belongs!