Thread: DE-Chrome-ing

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Once upon a time, I amagine that under the hood of my 64 looked real nice . Fender panels ,shroud, control arms,steering and much more was chromed .Now, 35-40 years later it doesn't look so good. Most is either rusting and, or peeling. We have some scientist,engineers and just some real smart people in this club ,so maybe someone here has a home remedy for cleaning this mess up.I don't have a clue other than take all parts to a re-chromer and have him acid strip it.Any and all help will be appreciated. THANKS!

Riverhorse59, Matoaca eh, it looks like we are very near in location. In my younger days I worked in two different commercial plating shops, but I have not kept up with current prices. You are probaby aware there are several plating shops in the Richmond area. One that comes to mind is the Clover Hill shop on Hull Street near the Chippenham Parkway. All I can tell you is that chrome can be removed by reverse electrolysis, so- called electropolishing, but I doubt if local shops do that since they are mainly set up to plate, not deplate. Of course paint is a possibility and after normal cleaning you could use aluminum spray can paint followed by some sort of clearcote. I am dressing up some rusted steel brackets on my 350 using this approach and it looks pretty good initially but you have to seal the aluminum paint or when dirt gets on it, it will quickly look shabby. Then there is the option of just cleaning off as much as will flake off with a wire brush, sanding with emery paper and using a thick primer before painting with the color of your choice. As far as replating goes the problem is that pitting will have to be fixed, probably by plating with Cu for several coats followed by buffing. The main thing I learned about electroplating is that nothing looks any smoother after plating than it looked as polished before! There are several other plating shops in the Richmond area so shop around and ask if they will "electropolish" some pieces for you but my advice would be to replate a few small pieces and paint the rest either body color or aluminum with clearcote. If you look at many rods from the '30s a lot of parts are painted where replating would have been hopeless. Of course in extreme cases of restoration where expense is not an issue a lot of pitting can be fixed by heavy copper plating followed by buffing and then rechroming. Unless you are restoring an old luxury car for high points, paint is a more sensible solution. In particular, pitting and other rough surfaces can be painted and sanded several times to regain a smooth surface. I would be careful with acid dipping, although there is a jelly with hydrochloric acid in it used by restorers sometimes. The problem is that when the rust is gone there is a hole or pit and some of the other metal goes with it. Yes rust needs to be removed and engine blocks are dipped in such a hot solution for that purpose, but sheet metal is more fragile than large cast iron pieces. If you want to dip the inner panel of a fender try talking to an engine rebuilding shop like Joe's Machine shop in Ashland. Also you want a "pickeling dip, acid", the caustic solution used to clean radiators will not do a very good job on rust since rust is intrinsically a base so you need an acid to dissolve it, not another caustic base. There is a guy who works at the Sears Auto (gave me a good deal on tires) at the Virginia center who totally stripped a Chevelle and he lives on Parham Ave in the west end of Richmond and my oh my did that Chevelle turn out nice (ironically he had it painted Mustang yellow). The engine bay of that Chevelle looks BETTER than new! (But does he drive it?)

Don Shillady
Retired Scientist/teen rodder

Tech1 is right, as usual! I was talking about sheet metal, but you mentioned structural suspension parts. While show cars often have outrageous amounts of expensive chrome plating on everything, there is a risk that during electroplating the H+ from the acid solutions involved in chrome plating will burrow into the interior of metal parts where it can recombine to form H2 or simple H atoms which displace metal atoms inside the metal and make steel brittle, so-called hydrogen embrittlement which weakens the parts ability to handle stress. Did I recommend paint?

Don Shillady
Retired Scientist/teen rodder

Thanks for the help guys. I think you're both over my head but I'll study your answers carefully. I may end up taking a rough sandpaper and the D.A. Then priming and painting. I had hoped to do a better job than that.Are You saying that parts like the upper control arm shafts have already been weakened by chroming or do mean that they would be weakened by the process of removing the chrome?

Tech and Don, I called a couple of plating shops today.one refered me to the other,I ask about the Hydrogen enbriddlement.The man said that does not apply to dressup or pretty type plating ,but it would apply to industrial or machinery type stuff. Whats the difference ? Is this true?He told me it might be a month or more before I would get my parts back. he did tell me that he cleaned the parts in 55 gal. drums with a mixture of sulfuric acid ,soda ash and water. he did not tell me in what proportions. Is this safe? what do you guys think? This is open to anyone who may have some ideas. Thanks!

Riverhorse, that acid stuff that they will drop your parts into I hear is good to do right after the company gets new fresh acid back in the tanks. Some people told me this and I read it in a few books. I think someone on here might have told me that as well, I don't remember. If the plating is comming off then try sand blasting the parts maybe. I am going to be sand blasting my grill, bumpers and a few other parts where all the chrome is peeling off and just powder coat them chrome instead of plating so I don't have to worry about chips and cracking or peeling.

Thanks, I was just thinking powder coating just before you posted but I think with as many parts as I have under the hood with chrome peeling off its not going to be something I can afford.I am not willing to spend too much money in this area when there are so many other things that need attention.Unless these guys that know about this tell me different I guess I will be sandblasting, DA-sanding,priming and painting .

Don't feel bad, I have to and will be having to do it the hard way like you with the sand blasting that will take forever and sanding with a jitter bug and DA. It might take forever but whatever get's the job done. If you don't care for it to be really nice or nothing then yeah don't spend a ton of money to powder coat or chrome plate or any of that stuff.

Well the dip is interesting and since sulfuric acid has two acidic H+ and soda ash is a mono-base, that solution is being set up as a buffer to keep the acid from being too strong since the soda ash would neutralize the acid if added in the right amount. If I had to I could calculate the amount of sulfuric acid and the grams of soda ash needed for 55 gallons, but it would depend on how strong the acid is as you buy it, Sp.Gr. of the sulfuric, purity of the soda ash etc. So unless you can get the recipe from that shop I would not try it, besides what do you do with 55 gallons of dilute sulfuric acid when you are done? There is a chance you could get into real trouble just trying to flush 55 gallons of acid. The summary of several answers is to sand blast, grind or sand the parts and then replate a few non-srurctural parts and paint the rest.

Don Shillady
Retired Scientist/teen rodder