Heckler
Well-Known Member
Autosol and a toothbrush, but 3m clean and polish was good as well, the important thing is the toothbrush
Removing surface corrosion from stainless
- Thread starter sarabande
- Start date
Autosol and a toothbrush, but 3m clean and polish was good as well, the important thing is the toothbrush
Heckler
Well-Known Member
I was taught many years ago how to use Brasso and or jewelers rouge on the injector nozzles of Rolls Royce Eagle diesel engines
Aja
Well-Known Member
ghostlymoron
Well-Known Member
Hydrofluoric acid is what you add to water to give it the fluoride for tooth protection. Needless to say, it's added in minute quantities and carefully controlled.
vyv_cox
Well-Known Member
I don't think that is correct. The fluoride in toothpaste is composed of various salts, including calcium and sodium fluorides and some others.
ghostlymoron
Well-Known Member
It's added at water treatment plants in acid form. Requires all sorts of special precautions due to its extreme corrosiveness including double walled pipework.
Tim Good
Well-Known Member
Easy, oxalic acid. Doesn't need to be strong. Whip on. Wait for rust to vanish. Rinse off. Rust on stainless gone.
I have to do it on my solar panel arches as they were built by food grade stainless which isn't polished to a shine and the tiny mat surfaces develops a layer of thin rust marks and on various of places which you talk of.
I have to do it on my solar panel arches as they were built by food grade stainless which isn't polished to a shine and the tiny mat surfaces develops a layer of thin rust marks and on various of places which you talk of.
RichardS
N/A
I'm sure Vyv is right and that it is usually sodium fluoride that is added to water supplies.
The only thing I can remember about concentrated hydrofluoric acid is that it had to be kept in plastic bottles because it dissolves glass, although how it was kept before bakelite was invented is a mystery (yes, I could Google it but I'm not that bothered.
). I also can't remember actually using it for anything interesting which is why I had large bottles of concentrated sulphuric, nitric and hydrochloric acid at home when I was a kid but no hydrofluoric.Richard
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vyv_cox
Well-Known Member
Apparently it is a by-product of the aluminium smelting process.
ghostlymoron
Well-Known Member
I'm only speaking from experience of re commissioning several plants in the Birmingham area in the 1990s which had been mothballed for many years but the local health authority decided to bring them into use to improve the dental health of the area.
I'm no chemist, but chemicals are often added to the public water supply in acid form such as orthophosphoric acid which is added to prevent dissolving of lead from ancient domestic pipework (known as plumbo solvency).
mogmog2
Well-Known Member
I would have thought it needed to be re-passivated for long term protection? I get that polishing removes micro-crevices, but doesn't the protective iton-free layer need to be reinstated.
As I understand it, that's what the pickling compound does, but this can also be achieved with various acids (which are slower) I forget which, but citric acid springs to mind. Or also electro-polishing, the kit for which which can be created with a bit of ingenuity and is good for cleaning awkward shapes.
As I understand it, that's what the pickling compound does, but this can also be achieved with various acids (which are slower) I forget which, but citric acid springs to mind. Or also electro-polishing, the kit for which which can be created with a bit of ingenuity and is good for cleaning awkward shapes.
vyv_cox
Well-Known Member
Chromium oxide forms on freshly abraded stainless steel within micro-seconds. Passivation is only required in special circumstances. Very few standard fittings in yachts would have undergone this treatment.