Cleaning copper

Author
Discussion

Len Clifton

Original Poster:

391 posts

5 months

Sunday 25th May
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I’m having a nightmare. Decided to remove a sticker on a large, copper lampshade. Thought I’d use some methylated spirit, but it’s left white residue which is proving hard to get rid of. Add more meths and it just makes things worse!

I also tried Brasso, but that left a black oxide, which is even more difficult to get rid of. Any ideas on the best way to clean copper, and leave it shiny? My plan is to apply a coat of lacquer, once it’s clean.

Thanks

SteBrown91

2,830 posts

144 months

Sunday 25th May
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Try some barkeepers friend? It’s what my nan used to use to clean her copper pots im sure

clockworks

6,769 posts

160 months

Sunday 25th May
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Are you sure it's not already lacquered?

With "bare" brass or copper, Brasso followed by a wash in warm, soapy, water does the job.

Simpo Two

89,060 posts

280 months

Sunday 25th May
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Meths doesn't leave a residue, so something's odd.

Worst case, wet/dry paper all over and start again...!

Billy_Rosewood

3,357 posts

179 months

Sunday 25th May
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Citrix acid will do it.

Len Clifton

Original Poster:

391 posts

5 months

Sunday 25th May
quotequote all
Simpo Two said:
Meths doesn't leave a residue, so something's odd.

Worst case, wet/dry paper all over and start again...!
It does react with copper and can cause it to oxidise. I’ve spent a good hour and a half on it this afternoon. It’s a nightmare.

Len Clifton

Original Poster:

391 posts

5 months

Sunday 25th May
quotequote all
clockworks said:
Are you sure it's not already lacquered?

With "bare" brass or copper, Brasso followed by a wash in warm, soapy, water does the job.
It was laquered with something, hence the idea to use meths to remove it, before respraying. Does the soapy water remove the black residue left by Brasso?

Edited by Len Clifton on Sunday 25th May 21:45

Aluminati

2,911 posts

73 months

Sunday 25th May
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Duraglit.

JoshSm

1,267 posts

52 months

Sunday 25th May
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If you want to remove copper oxides then something with oxalic acid can do it (Barkeepers Friend, or some cleaning products), or citric acid will do it too & is friendlier and cheaper. In theory the citric acid works as a passivator too and won't touch the metal.

I've used citric plenty of times on plain copper and it's very effective at getting it back to a clean state.

InductionRoar

2,107 posts

147 months

Sunday 25th May
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Meguiars metal polish.

Len Clifton

Original Poster:

391 posts

5 months

Sunday 25th May
quotequote all
JoshSm said:
If you want to remove copper oxides then something with oxalic acid can do it (Barkeepers Friend, or some cleaning products), or citric acid will do it too & is friendlier and cheaper. In theory the citric acid works as a passivator too and won't touch the metal.

I've used citric plenty of times on plain copper and it's very effective at getting it back to a clean state.
Helpful, thanks.

sherman

14,435 posts

230 months

Monday 26th May
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If you can remove any electrical connections and find a big enough container for the shade.

Submerge it in neat CocaCola (real not supermarket own brand) and leave it overnight.

Wash off any excess with soapy water.

That should clean it up

JoshSm

1,267 posts

52 months

Monday 26th May
quotequote all
sherman said:
Submerge it in neat CocaCola (real not supermarket own brand) and leave it overnight.
If you want phosphoric acid then one of the rust & calcium cleaners (like the Zep one) is a much cheaper option than Coke. HG Limescale Remover is another cheap option & includes some oxalic on top of the main phosphoric.

But citric is usually the ideal thing for plain copper.

clockworks

6,769 posts

160 months

Monday 26th May
quotequote all
Len Clifton said:
It was laquered with something, hence the idea to use meths to remove it, before respraying. Does the soapy water remove the black residue left by Brasso?

Edited by Len Clifton on Sunday 25th May 21:45
Yes, from bare copper. It'll be the remaining lacquer causing the problems with black or white residue.

I get quite a lot of brass components that were lacquered at the factory. The lacquer degrades over time, so needs to be removed, the metal polished, and sometimes fresh lacquer applied.
I use ammoniated clock cleaner to gently strip the lacquer, Brasso to restore the shine, and hot soapy water to remove the polish residue.


Len Clifton

Original Poster:

391 posts

5 months

Monday 26th May
quotequote all
clockworks said:
Yes, from bare copper. It'll be the remaining lacquer causing the problems with black or white residue.

I get quite a lot of brass components that were lacquered at the factory. The lacquer degrades over time, so needs to be removed, the metal polished, and sometimes fresh lacquer applied.
I use ammoniated clock cleaner to gently strip the lacquer, Brasso to restore the shine, and hot soapy water to remove the polish residue.
I shall try this, thanks.

dickymint

27,204 posts

273 months

Monday 26th May
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Brown sauce thumbup