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View Full Version : Best way to remove that green corrosion?


Ricohman
06-20-2006, 13:27
You know that corrosion.
The green stuff on camera bodies, not the stuff from leaking batteries.
Anyway, what is the best method for removing this stuff.
I know windex won't do it but a friend of mine told me to try toothpaste???
Any tips appreciated.

FrankS
06-20-2006, 13:37
easy fix: use vinegar
the greenstuff is an alkali, vinegar is an acid

Kim Coxon
06-20-2006, 14:11
Flitz from Micro Tools is very good for such things.

Kim

FrankS
06-20-2006, 14:17
Oops, did not read your post carefully. Sorry. Vinegar is for battery green goop.

Fedzilla_Bob
06-20-2006, 16:23
Actually, the green goop (copper oxide which is relesed from the brass) will dissolve a bit with white vinegar (tried it) then follow up with Flitz which will knock it out entirely. Flitz will also leave a protective sheen that helps prevent further oxidation on the areas treated.

But don't use it on a nice satin chrome though (like the old QL17s), it gets too bright. It doesn't seem to do this on an old FED though.

If this green stuff is coming from behind the leather you might have an uphill battle. I emphasize might.

Greyhoundman recommends toothpaste. I found that it works, but I think you might want to have the part off of the camera first to give it a good scrub with a soft toothbrush.

There is also a product in the US called Mr. Clean Magic Eraser. I've used one of these dry on a camera to pull dirt off of it. It works, but be careful of crumbs.
http://www.homemadesimple.com/sites/en_US/mrclean/products/eraser.shtml

I love my tube of Flitz.

ZorkiKat
06-21-2006, 03:56
Try q-tip or cotton wads dipped in metal polish. Give a good rubbing.

Ricohman
06-21-2006, 04:15
Thank you for the tips.
I will try all of these suggestions.

Mark Wood
06-21-2006, 05:04
Just a quick point (from a chemist - a dying breed in the UK!). The green residue is most probably what's known as the basic sulfate [Cu{Cu(OH)2}]SO4 (which is green) which slowly forms [Cu{Cu(OH)2}3]SO4 rather than copper oxide. My 1940s inorganic chemistry text book states that this forms in "town air." Copper(II) oxide is black and copper(I) oxide (which it certainly won't be) brown. Ammonia might remove it without doing any harm to chrome etc.

Mark Wood
06-21-2006, 05:24
PS. An outside possibility is that the green residue could be basic copper carbonate (which might dissolve in vinegar) but this is very much less likely than my first suggestion. The sulfate will have come by a roundabout route from sulfur oxides in the air - "acid rain" for want of a better title. If ammonia does remove the residue, don't be alarmed when the Q-Tip or cloth turns bright blue! This is the soluble copper(II) ammonia complex which will just wash away.
Sadly, corrosion is a remarkably complex topic. If only it was just oxidation...

FrankS
06-21-2006, 05:43
Great info, thanks Mark! From a chemical point of view then, what is best used to remove it?

Mark Wood
06-21-2006, 06:26
Hi Frank

Ammonia (the solution in water, not gas!) is probably the best bet as this might form the soluble, intense blue tetramine copper(II) complex - [Cu(NH3)4]2+. Just how soluble the basic copper(II) sulfate would be though, I'm really not sure and it may just sit there and do nothing. Copper sulfate itself dissolves to form this complex with no trouble but I suspect that the basic copper sulfate that makes up the green mess is not very water soluble - I'm pretty sure it's made in the lab. by precipitation from water. (I'm only guessing here as this is inorganic chemistry territory and I'm an organic chemist - any excuse!)
I suspect that very careful (i.e. with very light rubbing in the affected area only) use of metal polish polish might well be the simplest answer.

Fedzilla_Bob
06-21-2006, 07:09
Foiled again, by a chemist! Hah!

:)
Thanks for the info.

Flitz gives off an ammonia smell, along with something that smells like fuel. Maybe the ammonia in Flitz is doing the work of removing the corrosion.

Mark Wood
06-21-2006, 07:51
I'm pretty sure that metal polishes like "Brasso" also contain a small amount of ammonia which I assume must be to remove copper-based deposits - I don't think they're just abrasive.

Bill58
06-21-2006, 07:54
My two cents worth is to buy a "De-OXIT" pen from microtools. It works on all corrosion!!!!