stripping chrome from brass

plunger · Apr 25, 2020

Hi . I was hoping someone has successfully stripped chrome plating from brass faucets.Not knowing the proper terminology I suspect it is nickel and chrome plated.
I am from South Africa so I cant buy stuff from Caswells etc and need to try make my own formula, taking into considerations all the environmental problems(no environment police patrolling here,just common sense cause I like my planet) and the obvious dangers .
What I have tried. Being a plumber I have acsess to sulphuric acid. I mixed some borax and sulphuric acid and tried electrolysis using my inverter welder set on 50 amps and using a lead flashing plate as the cathode.

It stripped the chrome but also damaged the brass in the tap or faucet. I suspect the zinc is being attacked(dezincification)
I would love to hear if anyone here has done this successfully as well if you have done a small scale electropolish set up.

Street · Apr 25, 2020

From my limited understanding doing what you have done creates chromium compounds in the liquid which are extremely harmful to your health and harmful to the environment.
Hexavalient chromium is the compound i think.

so how do you dispose of the liquid you have now created?

Maybe someone will chime in on how to reverse the solution if possible.

plunger · Apr 25, 2020

Street said:
From my limited understanding doing what you have done creates chromium compounds in the liquid which are extremely harmful to your health and harmful to the environment.
Hexavalient chromium is the compound i think.

so how do you dispose of the liquid you have now created?

Maybe someone will chime in on how to reverse the solution if possible.

Being a dark third world country we just throw it down the drain. We have more to worry about like not getting murdered than to worry about a bit of environmental pollution.

To be honest I havent given it any thought yet. I have only tried it using less than two liters of water and about 150ml of sulphuric acid. The fact that this stuff is designed to be used on drains gives me some relief. The residue of chrome/nickel/brass and lead ,I have scooped off and binned it.

Rob F. · Apr 25, 2020

plunger said:
I was hoping someone has successfully stripped chrome plating from brass faucets
I am from South Africa so I cant buy stuff from Caswells etc and need to try make my own formula, taking into considerations all the environmental problems(no environment police patrolling here,just common sense cause I like my planet) and the obvious dangers .

Street said:
Hexavalient chromium is the compound i think.
so how do you dispose of the liquid you have now created?

plunger said:
Being a dark third world country we just throw it down the drain. We have more to worry about like not getting murdered than to worry about a bit of environmental pollution.

Maybe erin brockovich needs to come and vacation there?
You neighbors figure out you dump that stuff in the ground and they get sick you wont be worrying for to long.

Terry Keeley · Apr 25, 2020

HCL. 25-50% solution works well, warming it up even better.

Do it outdoors if able, the vapors will instantly rust anything zinc (galvanized pipe).

plunger · Apr 26, 2020

Rob F. said:
Maybe erin brockovich needs to come and vacation there?
You neighbors figure out you dump that stuff in the ground and they get sick you wont be worrying for to long.

I think you miss a bit of my sarcasm.This is a third world country ,we have alot of catching up to do in terms of ecological damage compared to what the States Europe and China have done.. But at two liters of water mixed with 125 ml of acid for a product sold as drain cleaner I seriously doubt Erin would bother. She has much more problems looking after damage the States does to the rest of the world than to bother about a home experiment.I am acutely aware of looking after my beautiful planet.
Do you know the answer.?

plunger · Apr 26, 2020

Terry Keeley said:
HCL. 25-50% solution works well, warming it up even better.

Do it outdoors if able, the vapors will instantly rust anything zinc (galvanized pipe).

Brass is made of copper and zinc . I wonder if it will cause dezincification of the brass. Is this done including electrolysis or just left in acid solution. ?

pcm81 · Apr 26, 2020

plunger said:
Hi . I was hoping someone has successfully stripped chrome plating from brass faucets.Not knowing the proper terminology I suspect it is nickel and chrome plated.
I am from South Africa so I cant buy stuff from Caswells etc and need to try make my own formula, taking into considerations all the environmental problems(no environment police patrolling here,just common sense cause I like my planet) and the obvious dangers .
What I have tried. Being a plumber I have acsess to sulphuric acid. I mixed some borax and sulphuric acid and tried electrolysis using my inverter welder set on 50 amps and using a lead flashing plate as the cathode.

It stripped the chrome but also damaged the brass in the tap or faucet. I suspect the zinc is being attacked(dezincification)
I would love to hear if anyone here has done this successfully as well if you have done a small scale electropolish set up.

Acid used to strip chrome will also attack zinc. Period. So you have to check the progress periodically to minimize attack on zinc.
If you want a more accurate way, you can try sand blasting if you have access to an air compressor.
Higher concentration of acid will eat away at chrome and zinc. Lower concentration will also create deposit of metal sulphate onto the part, which most of the time can be washed off, but may be a hassle. So if the "damage" you are referring to looks like holes or like metal was eaten away, sand blasting is your only choice. If the damage is formation of discolouration higher concentration acid may help, but it will eat away at the parts causing holes etc.

if you use electricity the reaction rate will be proportional to current density, so corners will have higher reaction rate and blind sports the slowest.

Terry Keeley · Apr 26, 2020

plunger said:
Brass is made of copper and zinc . I wonder if it will cause dezincification of the brass. Is this done including electrolysis or just left in acid solution. ?

Try it, it just works. Doesn't touch the brass at all.

We use it to strip chrome off the brass liners for our model engines.

edit: I looked at my notes as it's been a while, I used a 20% solution.

Dumpster_diving · Apr 26, 2020

No comment on the chemistry, but Caswell DIY nickel plating kits use much lower amperage. Like two D cell batteries. Maybe lower power would enable you to intercede more reliably.

Rob F. · Apr 26, 2020

Drain cleaner that has dissolved hair and soap is not the same as drain cleaner that has dissolved chromium and other metals in it.
Besides you are looking at it backwards, the "polluting" countries have a long way to go to get back to what you have there, not you have room to pollute since we are polluted.

plunger · Apr 26, 2020

Terry Keeley said:
Try it, it just works. Doesn't touch the brass at all.

We use it to strip chrome off the brass liners for our model engines.

edit: I looked at my notes as it's been a while, I used a 20% solution.

Terry I will give it a try.I see we have something in common.I have an emco compact 8 and also its daddy ,an maximat v13.

plunger · Apr 26, 2020

Rob F. said:
Drain cleaner that has dissolved hair and soap is not the same as drain cleaner that has dissolved chromium and other metals in it.
Besides you are looking at it backwards, the "polluting" countries have a long way to go to get back to what you have there, not you have room to pollute since we are polluted.

Rob you are one hundred percent correct with your statement. Dont worry i will bottle my 2l of dilute sulphuric acid .

Hardplates · Apr 26, 2020

Now that the safety police have said their part :rolleyes5:

I will quote and EPA agent, "The solution to pollution is dilution."

I'm not much with chemistry but I doubt there is much is anything that will dissolve chromium and not attack the brass.

pcm81 · Apr 26, 2020

Hardplates said:
Now that the safety police have said their part I will quote and EPA agent, "The solution to pollution is dilution."

I'm not much with chemistry but I doubt there is much is anything that will dissolve chromium and not attack the brass.

Correct. This is exactly why, every time I wash uranium down my sink I follow it up with 40 gallons of water.

Rob F. · Apr 26, 2020

pcm81 said:
Correct. This is exactly why, every time I wash uranium down my sink I follow it up with 40 gallons of water.

Or when I get to many old 5 gallon buckets around and have to burn them in the bonfire, make sure the big fan is blowing, need to dilute that thick black smoke with more fresh air ASAP.

Search

Largest Manufacturing Technology Community on the Web

Search

stripping chrome from brass

plunger

Aluminum

Street

Hot Rolled

plunger

Aluminum

Rob F.

Diamond

Terry Keeley

Titanium

plunger

Aluminum

plunger

Aluminum

pcm81

Cast Iron

Terry Keeley

Titanium

Dumpster_diving

Cast Iron

Rob F.

Diamond

plunger

Aluminum

plunger

Aluminum

Hardplates

Stainless

pcm81

Cast Iron

Rob F.

Diamond

Similar threads