stains in kitchen sink

[rthmjohn]

Don't ask how it happened, but I spilled bleach into my mother's stainless steel kitchen sink and it left patches of unsightly corroded metal. I know that the stain is chemical, but there's gotta be a way to reverse it or sand it off without further damaging the sink. Any suggestions? I don't want to buy my mom another sink. Any help is appreciated.

[Phi for All]

Sounds like you not only spilled it, you left it there a while. The big problem is, it's not really a stain, is it? It's corroded and pitted. You might try a 3M Scotch Bright Pad, type A, Grade Fine. Just rub lightly but thoroughly or you'll leave scratch marks. Follow the grain of any brush marks in the sink (if it's brushed stainless).

 

Can't say it will fix it, but it's a good cheap place to start.

[H2SO4]

or steel wool

or you can get a realy fine fine sanding pad and sand it while its wet.

[akcapr]

or you could try to electrolplate the original metal onto it.

[Silencer]

or you could try to electrolplate the original metal onto it.

 

lol. while you're at it why not just pour in some molten metal to fill in the pits? lol.

[H2SO4]

good one akcapr

[YT2095]

scrunch up some alu foil, it makes a good abrasive that won`t scratch the steel.

 

failing that do the bleach thing with the entire sink and pretend it`s Always been like that

[EL]

scrunch up some alu foil, it makes a good abrasive that won`t scratch the steel.

Aluminium will neither scratch not patch.

 

failing that do the bleach thing with the entire sink and pretend it`s Always been like that

Now that was a humorous but nasty idea to play on a mother.

 

No, the correct procedure to remedy the problem is to feel the stained area by your thumb and check if it was badly corroded or simply stained.

If it was only a superficial surface stain then [math] \cf{NH_4OH}[/math] (ammonium hydroxide) should do the trick.

In all cases, you might need a flat grinding stone (1" x 1") grit => 1000 and pumice stone powder to remove roughness.

 

The ultimate remedy is to apologize for the unintentional minor damage or remake the kitchen.

[YT2095]

it`s not meant to "patch" it is meant to remove the least hard (iron chloride) in this case, better than a grit based compound that WILL SCRATCH, sodium Bicarb will work as well as Ammonium hydroxide AND have an abrasive quality too.

 

as the "doing it to the rest" well, ya never know, if things get TOO BAD! and all that

[EL]

YT2095, do you know the composition of metal polishing compounds?

[YT2095]

some of them yes

 

Bicarb is usable for most easily sratchables, if you don`t have any, use a smokers toothpaste, that works like a charm too

[EL]

I used to manufacture metal polishing compounds, which are patented proprietary secrets.

That is why I fully know what I am talking about and bicarbonate will not achieve the objective and neither does extremely soft abrasives. The reduction power of ammonia is precisely required to achieve what patented proprietary chemicals will in removing the oxides and chlorides of metallic alloys on stained stainless steal, which is not pure iron at all. The flat grinding stone at 1000 grit or more is empirically tested to polish and sharpen SS knives, while the pumice stone powder is used as a vehicle when wet with water.

 

What you do not seem to know is that aluminium foil itself will stain the stainless steal with aluminium oxide if it was rubbed into the corroded surface.

 

Kindest regards.

[YT2095]

bicarb and alu in boiling water will polish up silver, test it for yourself

 

1000 mesh will still leave a noticable effect after the stain is gone (even some household cleaners will do this, I worked in a plant that manufactured and bottled them too). Calcium Carbonate at that mesh will work however (and that`s used in polishes too).

 

the effect of the alu is easily removed as it`s NOT a stain either.

 

I do understand what you`re saying, I`de just go a more cautious route 1`st though

[EL]

bicarb and alu in boiling water will polish up silver, test it for yourself

Oh! But I did know that very well, however what works for silver does not work for stainless steel sinks.

 

1000 mesh will still leave a noticable effect after the stain is gone (even some household cleaners will do this, I worked in a plant that manufactured and bottled them too). Calcium Carbonate at that mesh will work however (and that`s used in polishes too).

Industrial abrasive compounds are complex mixtures, not just a filling powder.

I may disclose the fact that aluminium oxide is a popular ingredient in car-body-polishing-compounds, while more expensive and more potent compounds contain silicon carbide powder, but calcium carbonate or zinc oxide are usually used as fillers and vehicle media to homogenize and distribute the effective abrasive grains as well as a whitener.

Pumice and gasoline were common ingredients for brass polishing compounds in England long ago.

The modern technology combines the mechanical and the chemical effects to maximize the polishing results.

 

the effect of the alu is easily removed as it`s NOT a stain either.

Now it is your turn to test it for yourself, because I am quite sure that aluminium foil will "stain" (discoloration) corroded stainless steel, and it is not as easy as you think that it could be removed especially if it was strongly embedded and oxidized.

 

I do understand what you`re saying, I`de just go a more cautious route 1`st though

 

I understand what you say too, and I like the quality of your posts too, but here I am an authority with an academic degree combined with field experience. However, you may continue to argue if you wish and I shall adequately reply too.

[YT2095]

ok, In reverse order, no-one`s arguing with anyone (I didn`t think so anyway), sharing data is what it`s all about here

 

I have actualy tested this myself in the past, and also the smokers toothpaste "trick", both worked just fine, the alu left a dull grey mark, that came off easily with simple detergent. the only stain I have to this day in my sink was from Boiling Nitrating mixture (conc nitric and Sulphuric acid mix), the vessel cracked and I moved it over the sink in time, I`ve not been able to remove this mark and the fingernail test is positive, it`s properly etched. Chlorox stains are surface at best, and a good SS alloy won`t mark with Hypochlorites anyway.

 

as for industrial abrasives such as carbides and nitrides etc... this still seems a little overkill for a Chlorox stain, I`de be inclined to use that when all else failed (personal pref).

 

the old Alu pan and bicarb with boiling water and the family silver imersed trick,does work with other metals too, I`de be tempted to try that 1`st for the same reasons outlined above.

 

[EL]

There is no harm in testing, and I encourage the OP to use your method first to gain experience and know the difference.

[YT2095]

EL,

just out of curiousity, what would you reccomend for my sink? I`ve just about given up with it and resigned myself to living with it, as it`s an actual Removal of the metal and the discoloration is shadow lines basicly, I though about doing the same thing again but a waeker soln to try and "Even" it out a little.

it doesn`t really bother me, in fact I don`t even see it anymore, I`de be interested to see what product might shift it though.

 

Cheerz

[EL]

Metal nitrate is water soluble but metal sulphate is not.

Then you have to test if the discoloration had ferric sulphate involved or not.

You say that the surface is etched as well, and there is nothing you can do about that else than using moulding templates' high speed motor driven grinding tool-tips to smooth it out.

Then you can finally polish it.

Make sure first that the etched grooves are not too deep because living with discolouration is better than living with a sink that has a hole in it.

[YT2095]

living with discolouration is better than living with a sink that has a hole in it.

 

LOL, too right!

 

I think I`ll just continue to live with it

 

edit: I`ve just found some P600 wet`n`dry cloth, recon that`ll help, or shall I just ignore it?

[EL]

It depends on "how good looking" a chemists sink should look like, in your opinion.

On campus, we had those chemical resistant sinks in the laboratories, but how many colours do you think I counted one day in one of them?

I lost count.

[YT2095]

Ewwww!

 

I`m just grateful I don`t do Biology now!

[rthmjohn]

I rinsed the bleach away quickly and the stains are superficial...

[Phi for All]

Nice of you to stop back by!

I rinsed the bleach away quickly and the stains are superficial...

In that case I would choose the least abrasive of the solutions we've given you here and start with that. You can alwasy go stronger but you can't go back if you scratch it all up by scrubbing too hard.

[rthmjohn]

Hey, it's been a while, but I tried that aluminum and bicarb thing and it didn't work...

It just left a black residue (aluminum oxide i'm guessing) that I had to wash off. Any other suggestions?

[Arthur Dent]

Look for "Cameo" anti-tarnish cleaner. At first it looks like plain Comet or Ajax scrubbing powder, but it has this strange licorice aroma and after scrubbing it on steel with a wet sponge for 2 or 3 minutes, it does wonders even with the most deeply stained sinks. I had a sink that was utterly destroyed by corrosive reflux from the drain that did its work during a whole weekend... well that Cameo powder made it look nice and shiny! It's about $3 to $5 a bottle and is available at many drugstores and hardware stores.

 

Robert