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  for Metal Finishing since 1989
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Asking for formula for hydrochloric acid to strip motorcycle parts

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(a fun & ridiculous thread, especially for dog lovers, spanning from Christmas season 2001 to 2020)

! Upon leaving the gym this afternoon, I decided to make the 40 minute trek to Boston to finish my analysis of the afore-prepared sample. The results, along with other observations, are listed as follows:

1. The chemical formula for chromium chloride is CrCl3.6H20. Synonyms (consult your local MSDS sheet) include Chromium (III) Chloride Hexahydrate. The "hexa" only means that 6 molecules of water remained attached to the chromium chloride compound following the evaporation process. The Cl3 indicates that the Cr cation was raised unto it's TRIVALENT state by hydrochloric acid. Not unto it's hexavalent state. As I stated in an earlier entry, hydrochloric acid raises chromium metal only unto it's trivalent state; an active (unstable) oxidizer is required to raise it from it's trivalent unto it's hexavalent state.

2. The results of my total analysis of the prepared HCl stripping solution are as follows: * Of the total 200 mg of metal stripped from the socket, 115 mg (57.5%) were detected as trivalent (III) chromium, 84 mg (42%) were detected as Fe+ iron, 1 mg (0.5%) was detected as hexavalent CrVI chromium. I lay the fruits of my labor at your feet, my dear colleagues, and such with, beg your approval.

Truly,

Randall Fowler - Fowler Industrial Plating, LLC
Cleveland, Tennessee, USA
2002

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2002

Wow what a dazzler this thread has been. Thanks to Freeman for pointing out this one. I feel cheated that I was not a member of this group in time to contribute.

I heard a rumor that the poor b@@@@@d who wanted to refurbish his bike actually sold it and bought a dog.

I have learned a huge amount from this interchange.
1) It does not matter what the subject matter is you can always talk about your dog instead.
2) Do not mess with Randy Fowler.
3) Do not mess with Randy Fowler.
4) Do not mess with Randy Fowler.

Randy Fowler admitted in public that he has a CAT. I think he should be kicked off this site........oh yeah. Didn't he say he went from the gym up to Boston.......ooops. Guess he works out too.
5) Do not mess with Randy Fowler.

Have a great day and thank you all for a lot of smiles I got from these posts.

PS I have got a Pit Bull (American Staffordshire Bull Terrier). She is the sweetest little dog with a beautiful nature. She is the hit of every party she is taken to and she goes to a lot. It ticks me off. She is far more popular than I am. Hrumph

John Holroyd
- Elkhorn, Wisconsin

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Hey Mr. Holroyd,

Right now Randy Fowler is laughing and shaking and weeping at your entry! I feel so good I could just drop kick Rocky (my CAT) into the living room! Please mess with Randy Fowler; gives me a "spring board"! Perhaps another letter, another time. Thanks!

Randall Fowler - Fowler Industrial Plating, LLC
Cleveland, Tennessee, USA
2002

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Hey Randy,

That one had me chuckling pretty good too! I replied to the Superbowl thread, but I think my note was deemed inappropriate, as it wasn't published. Sigh.. sometimes I'm not the most politically correct guy in the world.

Marc Green with Rusty
anodizer - Boise, Idaho
2002

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Hey Marc,

As a member of the RNC, political "correctness" (correctness?...HA!) does not define my profile, either! How are the gals in Idaho? This hunter and fisher from the PC "Commonwealth" of MA may just want to make a move! Talk to ya' "late-ah"!

Randall Fowler - Fowler Industrial Plating, LLC
Cleveland, Tennessee, USA
2002

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Ahhh...the gals of Idaho, ya gotta luvem! And.. what's REALLY nice is they understand a mans need to hunt and fish (Idaho's hunting and fishing is surpassed only by Alaska, in my humble, if somewhat biased, opinion).

Marc Green with Rusty
anodizer - Boise, Idaho
2002

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It kind of makes me long for the days when we chatted about our dogs.

  
Tom Pullizzi
Falls Township, Pennsylvania
2002

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Tom,

Might I remind you..that on Jan 9th  (scroll up), that you called for "The end of the fascinating, if somewhat disgusting, repartee about dogs". Dayum...only 10 months and a week or so till 2003! Can we actually keep this one going that long?

Marc Green with Rusty
anodizer - Boise, Idaho
2002

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2002

Dogs! Did someone say something about dogs? I'll take a piece of that, oh yeah I still have to follow up from my input of Jan 15, 2002, (I'm thinking I'll only be giving Randy a chance to say told you so, but I deserve it.) Yes this thread will live on to at least 2003.

Jon Quirt
- Minneapolis, Minnesota

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Once a long time ago I was told by a teacher to all ways read the question then answer it, then read the answer to check you have answered the question.

The answer to the question is: You can make hydrochloric acid by adding concentrated sulfuric acid to common salt and bubbling the hydrogen chloride gas into water where it will form hydrochloric acid.

However I would say this is probably as dangerous doing as making mixture of sulfuric and nitric acids adding glycerine pouring the lot into a large volume of water and scooping the explosive nitroglycerine off the bottom.

I tell you to do neither of the two above chemical reactions.

Getting back to the real world if you still read this page (and why not as it has it all comedy, chemistry, dogs and some good advice)

You only say that the parts are poorly chrome plated not when or where they were chrome plated.

Reworking the parts your self is fine in that you can get the chrome off using brick cleaner but then what next?

You will probably be left with an under coat which the only possible option to you could be to polish off with a buff on an electric drill which may then effect the parts, you would probably polish off the edges, drag holes and generally make a mess or at least I would.

If you get through this you will be left with bare part which you will want chrome on once more so you have to go to a finishing house to have done anyway.

Try the job shop listing on the home page and you will find someone who will be able to strip the parts back and re-plate them.

Now that is done time for me to play catch up on the rest of the stuff

Muriatic acid is the old trivial name for hydrochloric acid just as caustic soda ⇦liquid caustic soda in bulk on Amazon [affil link] is sodium hydroxide (some names take longer to die than others, or it may be the users of the names take longer to die).

The analysis of the stripping was of interest to me but I have had the thought are the results posted as elemental chrome and iron as there may be further reactions, I am away from my table of electrode potentials but the thought which I had is: Is the iron coming off as Fe 2+ and getting oxidised to Fe 3+ by any Cr 6+ which is present which would thus be reduced to Cr 3+. However away from my electrode potentials and atomic weights I can not do the math to see if it is even possible.

The other simple answer which I will try once I finish my holiday is to check our hydrochloric chrome strip for Cr 6+.

As they say leave the best to last and here are the pooch pictures.

(Check with Ted but I think I lead the way here when I first sent in the picture of my two dogs Harvest (Harvey) and Griffin (Griff) asleep on the sofa with me)


Griff on the mat which hides where he ate the carpet.


Harvey with the 'you don't expect me to move look'

For those who might be interested these are cross breed Whippet and Hungarian Vizsla.

From the Vizsla they have their colouration, good noses, and tendency to chew anything and everything from the Whippet they have general build and ability to run like the wind.

They were rescued from the streets of Wales so I have no history from them and they are about 12 months old.

I am biased of course but they are the best dogs in the UK on this site.

I hope this helps the letter run for a couple more weeks as I have had a good laugh reading it and it has got my mind going on the chrome strip side as well.

Hope all of you are well and will mark this as the page to read.

Martin Trigg-Hogarth
surface treatment shop - Stroud, Glos, England

Hmmm, so you say that I could make hydrochloric acid by using sulfuric acid and common salt. Can anybody tell me how to make sulfuric acid? Perhaps it involves the use of copper iridium coins and rice...

Bill Mingarell
- York, Pennsylvania
2002

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I'm a newcomer here but, I was in a classroom with approximately 15 open beakers with Hydrochloric acid in them and, rest assured, it is not that noxious and choking. Secondly, whoever said that baking soda would get rid of the acid, they're technically right. The baking soda, being a base, will neutralize the acid admirably (particularly with the water in there as well). And, as dangerous as dumping leftover stomach acid down the drain sounds, I'm almost positive that the numerous filtering technologies that are used would take it all out. Besides, hydrogen peroxide and bleach are used to clean public water anyway. This brings me to my question though. Can anyone tell me the procedure for making HCl? If not then can someone point me in the right direction? I know it's the combination of Bleach and hydrogen peroxide but I don't know how much of either one to use. I would buy the muriatic acid (or whatever you called it) but I need the full acid. Putting water in the acid causes the acid to neutralize a little bit.

Tim Hamilton
- Macomb, Illinois
2005

Strong hydrochloric acid is readily available from most chemical suppliers for shipment to any industrial facility, you don't have to make it, Tim. Commercially it's manufactured by the direct combination of hydrogen and chlorine gases, which is something you simply can't do at home. In the lab, as previously mentioned, it can be made from boiling sulfuric acid and table salt. "Vitalized Chemistry" by Dorin [on on Amazonaffil links] will show you the lab setup to do this. Good luck.

Your assertion that it is not noxious and choking is incorrect though, and is based on limited data in a specific circumstance. There is a big difference in the rate of evolution of a gas depending on whether the liquid sits stagnant in a beaker vs. being splashed around. Shake hot water in a cocktail shaker set to appreciate this. Don't shake hydrochloric acid in the shaker set; you'll be knocked over by the noxious, choking fumes :-)

Hydrochloric acid differs from stomach acid not only in concentration and volume, but also because of the heavy metals dissolved in it by the stripping reactions we're talking about, which make it a categorically regulated toxic waste.

Hydrochloric acid is not made by mixing bleach, which is a strong alkali (NaOCl plus lots of NaOH) and hydrogen peroxide (H2O2), but experimenting by mixing bleach with things is very dangerous because of the strong possibility of releasing chlorine gas, so please be careful, and if you're going to experiment despite warnings, do it in the open air in the backyard.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

Would you have guessed this thread would advance into 2006? Found it by looking for entries on HCl - as an amateur mineral collector I want to assemble my own field test kit & didn't know what HCl was, nor what a "base" would be ... Very funny & intellectual page: love it! **I think Marc's objection to the proposed used acid going down the drain wasn't necessarily about the acid itself, but the toxic metal byproducts of the stripping that would be in it ** .... As for cutest dog... My daughter's dog is a 6.5 Yorkie who really looks like a silky - I love little dogs now that I know him ... All dogs are cool & cats are cool too, for the dogs to chase, ya know ... I am partial to the short hairs presented here.

Kate Miller
rock collector - Eugene, Oregon
2006

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2007

Looking For Info on stripping Chrome Of Bike parts, stumbled on this Thread.
I will be using a Pro to strip parts( great info )
PS it looks like the thread made it to 2007

My Black lab, Dutches (passed away in 03 after 19 years) was THE BEST DOG EVER!

Ray Bernache
- Fairhaven, Massachusetts

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Hey everybody,
What a wonderful surprise to see that the most popular thread in Finishing history made it all the way to 2007. I'll be opening a new metal finishing facility early next year in Cleveland, Tennessee. If we have a bit of a slow start, at least I know how to make hydrochloric acid which people can spill on their pants so they'll have to buy more.
Hee...hee...hee...
Say hello to Fairhaven, Massachusetts for me. Lovely city and I miss it.

Randall Fowler - Fowler Industrial Plating, LLC
Cleveland, Tennessee, USA
2007

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I don't worry about neutralized HCl hydrochloric acid down the drain if done safely and properly. acid + base = salts, example hydrochloric acid + sodium hydroxide (caustic soda ⇦liquid caustic soda in bulk on Amazon [affil link] ) = sodium Chloride (table salt) note acid and base both very strong can burn etc are neutralized to something we eat, now kids, salt is cheap and if your gonna eat it, buy it. your healthcare is not cheap. as far as removing chrome ---as far as I know chromium is a very deadly poison and the sewers go back to our water supplies where we get a drink, wish people would learn this from centuries of diseases and cancer etc we don't teach it or don't care? my advice go to junk yard etc get another bike part and help keep us all healthy,

Richard Butcher
engineer trch - Selma, Oregon
2007

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You asked a simple question, and instead of just giving you an answer, it seems that the control freaks decided to pass judgment on your intelligence and to proceed to instruct you on the "correctness" of your application. Obviously, some need to pontificate. There is an old maxim: "don't throw your pearls before swine." Any idea is a pearl, and who knows. . . you may in your experiments concock a better way of doing things. It's certainly been done before!

You can easily make dilute HCl by adding table salt to vinegar ⇦in bulk on eBay or Amazon [affil links] . The result will be no stronger than the (usually 5%) concentration of acetic acid in the vinegar. Stronger concentrations can be produced simply by a distillation process. Hope you finally have the answer you sought.

Best wishes from Doc

Thomas L [last name deleted for privacy by Editor]Ph.D.
- Graham, Texas
2007

I'm a hobbyist and restorer of old cars and motorcycles . Lately I dipped parts from the interior of a door in muriatic acid for a short period of time and they came out looking like new ! I think the parts such as window channels and door latches are cad plated , but not sure . My idea is that since the parts are somewhat protected from the elements , they only have a slight surface layer of rust or oxidation . By dipping for a short period of time , the cad plating is not seriously damaged ? As always I rinse the parts with water and as always the part starts to oxidize immediately - a major disappointment , considering how beautiful they looked when pulled out of the dip . I know from experience there's no chance of stopping oxidation after using muriatic acid on bare metal , but in this case the plating looked unphased . Is there a way to wash off the muriatic acid with something other than water . I am assuming the water is starting the oxidation . If the plating is intact is the oxidation just the residue laying on top of the plating ? On a few parts I sprayed clear lacquer over the rinsed plating and it seemed to prevent any further oxidation , however is wasn't as nice and silvery as when pulled out of the muriatic acid dip . Any help would greatly be appreciated ! Skip

Skip Rec
- Los Angeles, California
2007

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Skip, you are right that hydrochloric acid removes rust very quickly but, in turn, leads to flash rusting. Maybe a dip into or wipe with naval jelly ⇦this on eBay or Amazon [affil links] will solve the problem. Good luck and please let us know.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

Today is December 20th 2008 and while I have no picture of a dog or comments/ suggestions about stripping Chrome I felt compelled to post a note.

I was led here while researching the following on google (blue exhaust cleaning) ⇨

Fun thread I hope it stays active for many more years to come.

Feliz Navidad

Johnny Q
- Ocoee, Florida
December 21, 2008

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Hello all,

Thank you for having such an exhaustive thread.

I have some silicon bronze deckplates with a old and worn chrome plating. These go on my sailboat, to which I attach cowl vents, or the plate to seal the deck. I was hoping to strip the chrome down to bronze as it is quite good at taking care of itself, and the chrome looks poor.

A friend suggested I buy some HCl or muriatic acid, from a pool supply store, put it in a plastic container of sort. Then put the negative lead of a battery charger ⇦this on eBay or Amazon [affil links] in the container, hooking the positive to the thing I want to strip, then pass the plate through the solution. Supposedly it will fizz, turn green (like antifreeze) and whalla! No more chrome.

I didn't see this mentioned in this thread, but I claims to have done it. How does that work?

Thank you for your time!

Aaron Norlund
- Englewood, Florida
February 22, 2009

I came across this thread while looking up muriatic acid. Lots of good advice and many laughs. One thing tho, way back in ought five Tim Hamilton made a remark about pouring water in the acid. I thought that was a major no-no.

The weenie dogs were bred for going down holes after Badgers, hence the name. Dachs ("badger") and Hund("dog").

David Henderson
- Reno, Nevada

Ed. note: "Do as you oughta, add acid to water" -- spoken with a northeast accent

I Googled "removing chrome plating" and it brought me to this forum. Unfortunately, I don't currently have a dog but after reading this forum I do have a headache :-)

Thanks for the valuable info (take my stuff to a professional) and the many laughs.

woof woof

Robert Banks
- Palm Beach Gardens, Florida

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WOW, I was surprised this was still goin since 2002...Welcome 2011!!!

I found this searching for a way to remove chrome off motorcycle parts to prep for powder coating.

I'm going to have an un-employed friend try the techniques mentioned as he has the time and the home owners insurance if something goes wrong.

Michael C [last name deleted for privacy by Editor]
- San antonio, Texas, USA
January 3, 2011

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Ed. note: And if something does go wrong, well, we could always use a photo of his guide dog to round out the album :-)

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Thanks for the info. I was looking for info on removing the chrome plating on the rear door of my skoolie so that I can paint it a different colour. Google sent me here. Thanks.
1/04/2011

Lorna Schinske
- Socorro, New Mexico USA
January 4, 2011

Hi, Lorna.

Getting adhesion of paint onto chrome is exceptionally difficult. Getting adhesion onto nickel isn't easy, but is a bit better. I have heard from powder coating shops that they have achieved success with a light sandblasting. So, the possible approaches could include:
- just removing the chrome with hydrochloric acid, then using a self-etching primer to try to get adhesion to the nickel, or - removing the chrome and roughening the nickel by sandblasting, then using a self-etching primer. Good luck.

If you try it, please let us know if the paint sticks well enough for you. Thanks.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

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I thought I would try the "just removing the chrome with hydrochloric acid, then using a self-etching primer to try to get adhesion to the nickel". There are a few small things that I want to "de-chrome". This is a 1986 BlueBird school bus and the chrome is still in good shape. I just dislike chrome. I will post back as to how it turns out.
Lorna

Lorna Schinske
- Socorro, New Mexico USA
January 5, 2011

After reading all the posts here and going through the annoying nonsense about dogs (I like cats, dogs are not an option IMO especially since my GF has a rat terrier which is the most sinister creature known to man) I decided to take two new stock chromed mufflers to have them sand blasted, and whatever they are using for chrome these days came off quite easily. And this is the reason for my post: there seems to be a difference in the chrome process these days, especially for recently chromed items from California. I understand this thread is about restoration/ removal of chrome, so the existing chrome is likely to be by the traditional (old) method. But wish to point out that with the new methods being used for "chrome" - which seems to be more akin to a polished paint - messing with hazardous chemicals might be a waste of time, if you are dealing with items "plated" using the new method.

Steve Bruce
- Pahrump, Nevada, USA
June 24, 2011

I came across this thread after googling muriatic acid/HCl. my desired application involves a mineral specimen - the specimen is a very nice azurite crystal (azurite is a copper carbonate) that has a thin coating of limestone (calcium carbonate). I wanted to use the HCL to affect the limestone, but am afraid it would also affect the azurite - just trying to see how careful I need to be in not overexposing the specimen to the acid, not knowing if copper carbonate ⇦this on eBay or Amazon [affil links] and calcium carbonate would respond equally as quickly to the acid. but then I misread the thread and used HCL to strip my dog, maggie, which is now a hairless border collie. my cats are laughing at maggie and I'm considering dipping them as well. I enjoyed this thread and would appreciate any thoughts about the proposed application for the mineral. peace. penney

Penney File
- Lusby, Maryland, USA
August 5, 2011

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Well, now, how about continuing this thread into 2012? While I do have a motorcycle, it's bright green and doesn't need re-chroming. I don't have a dog. I have two cats which, I hate to say, are stealing oxygen from other much more worthy animals that may need it.

What I really need help with is stripping a thin plating finish off of a golf putter. I'm willing to try mixing some vinegar and salt and dipping it in, but it isn't a chrome finish. Any ideas and thoughts about how to remove a plating from a carbon steel putter head?

Shawn Watts
- Casper, Wyoming, USA
April 28, 2012

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Dear Sirs,

I currently restore Lambrettas in England and the cheap Indian chrome plating on levers and headlight rims is a major problem.

I have read all your posts in detail and after careful and considered deliberation, much research and hours going through periodic tables and alkali levels I have decided to give up and buy another dog.

Hope this post finds you all well, good luck with the finishing in the future.

Joe McNamara,
Blighty

Joe Mcnamara
- Middlesbrough Cleveland England
June 12, 2012

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Q. Google is still sending people here.

So, do I have this correct?:
-muriatic acid will remove chrome
-muriatic acid will not remove the nickel undercoat
-muriatic acid strips the chromium as trivalent chromium not hexavalent
-the stripped part needs to be neutralized in a baking soda bath
-the baking soda solution will also neutralize the muriatic acid
-milk of magnesia (magnesium hydroxide) also will neutralize muriatic acid and is safer than baking soda
-sewer disposal of the muriatic acid is legal after neutralizing in the baking soda solution?

Jake Dyson
- Vancouver, BC, Canada
September 11, 2012

Thanks Ted,
Just for interest, consider this, people use Drano to unclog sinks. Many sinks have chrome clad traps. Drano is sodium hydroxide which is also used to remove chrome. I don't know if an electrical current is absolutely required though.

Reverse current stripping with sodium hydroxide produces hexavalent chromium!

The next time the wife's hair clogs the sink we could be polluting the water supply with cancerous chromium, oops!

Jake Dyson [returning]
- Vancouver, BC, Canada

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Testing if there is nickel plating under the chrome

Q. Hi,

Could you expand on why HCl, hydrochloric acid, would not touch the nickel layer in a decoratively chrome plated part?

Our current situation is that the plating of the decoratively chrome plated brass part is being rubbed off. The brass is exposed in some area. We would like to verify whether the nickel layer was there.

We used muriatic acid / HCl suggested in this post to test a small spot. The area turned green and the brass material underneath is exposed. But we looked up online and both reaction to either to produce chromium chloride (?) and nickel chloride (?) could be green. Is there a conclusive method for testing for the presence of Nickel on a decoratively chrome plated part?

Thank you very much for your help.

Jessie Chu
- City of Industry, California, USA
November 18, 2016

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! I have a batch of old Rover car blocks. Upon removing the core plugs, the silt build up of rust and crud is crazy; it is solid.

I am not interested in Molasses as it takes too long, nor eco-rust descaling methods. I want to dunk the blocks into a strong acid that will really attack the crud. For this I am going to use HCl acid as I believe it will be the quickest method.

I don't want any clever remarks or comments; I am fully aware of how to neutralize it afterwards, and flash rust. I have a 200 litre barrel full of diesel to dunk the blocks into after a wash in water.

I am only writing this because it is the only forum I found on the web with the most info on HCl and rust.

Mick eyy
- Cambs, UK
December 6, 2017

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A. I also was looking to clean up some chrome parts before sending them to be powder coated. (Heavily damaged with salt corrosion my bad.) Thought I would add a revival post and date it.

As to making any form of acid, if you don't have an education in chemistry don't try; if you don't have a laboratory don't try. Fist educate yourself on the chemicals you are thinking of working with, including but not limited to their effects, storage and disposal.

Have a great one!

Ken Galbraith
- Nova Scotia, Canada
September 3, 2018

A. I liked Jim Treglio's idea of using a magnet to check if a brass part has been nickel plated. So I tried it by placing a small (6x4 mm) neodymium magnet on the vertical surfaces of my plated part. It stuck in some areas of the part but slipped off in other areas, so it also proved to be a good indicator of the relative thickness of the nickel plating over the surface of the part.

Tony McDougall
- Adelaide South Australia
September 2, 2020