I repaired some stainless trim on my 61 olds and i noticed that when I started polishing, everywhere i did a repair (dent removal, file, sand) I broke through a ‘coating’ that is on the surface. The appearance is different. In order to make the stainless the same ‘color’ id have to sand the whole piece! Is this typical?
Some stainless was flash chromed. If you have a chrome shop close by they can reverse strip in caustic to remove. I first noticed it on 55-7 T Birds and the tailfins on 57 Chevys. I imagine they did it to make the color uniform with chrome parts and to add a little scratch resistance.
check piece with a magnet, if there is an attraction its a higher iron content stainless and probably flash coated with chrome
Are you sure you were dealing with stainless steel? Anodized aluminum also has the characteristics you describe. To restore the finish, it must be anodized after repair. Ray
Every stainless part on my '57 has a magnetic attraction, just much less than regular steel. I've restored all of it, and none had a flash coating.
Every 50s Mopar has this. Makes it a huge pain to restore the trim. Interesting tip on having a chrome shop strip the flash chrome first.
The coating is very tough to sand, the stainless is much easier to sand and polish where that coating is gone
Same thing happened on my Lincoln , was told it was flash chrome. I just polished it. It looks very good and no one notices it.
Never heard of Factory Chromed Stainless. Too much expense . Aluminum anodizing can easily be removed with Oven Cleaner, so I would try that. And you Do Not have to re-anodize when done. (I’ve had Trim last years with no ill effects).
The stainless on my '59 is the same, someone here said it was a 430 series of stainless. Probably easy to form and it polishes up nicely.
I'm very curious to see pics as well. I've heard about the flash chromed stainless many times over the years from many different people, but I also worked at a chrome shop for years and have dealt with a ton of stainless molding for old cars and I have never personally run into it.
All auto manufacturers used the "flash" chrome process up through the early 70s because of the low nickle content of the materials and also - they could never have afforded the labor and skills costs related to having hundreds of people behind the assembly lines polishing stainless trim for your cars. 1957 Chevies, 1967 Corvettes, 1972 Chevells, both Ford and Chrysler did the same thing. They all had an optical standard that the trim parts needed to comply with, and because of this, parts were sometimes made from other materials than stainless - steel brass, copper etc. I had several examples of 57 Chevy tail fins that were regular steel and also brass; this was probably due to a supplier not being able to fill the stainless order and they just used what ever would "chrome plate" to meet the standard set. I polished stainless for nearly 40 years and ran across many weird things that most would never believe. Most manufacturers began switching to aluminum moldings that were bright anodized for appearances and cost savings. You do not need to have a chrome shop remove the coatings, just use regular swimming pool muriatic acid "OUT SIDE" and leave the moldings soak for a few minuets, then neutralize it with water and you are ready to repair, sand & buff it out. Long moldings need a tray, like 1/2 of a tube or a rain gutter, and curved moldings need a bucket because of their shapes. This will remove 95+% of the chrome and the balance will come off in the polishing process. Mill quality stainless was NEVER polished before plating, it was just a good grade that accepted the process so your moldings would look bright & shiney on your new car - once you strip the coating, inspect it carefully with a good magnifying glass and you will be amazed at the number of surface imperfections that show up without the chrome hiding it from the naked eye. Stainless moldings rust and pitt, and sometimes they could not be brought back to a mirror finish because of their low nickel content. Any questions.... I'll be glad to pass on my experience to anyone willing to take their life and extremities to the limits - all band-aids & stitches are at your own risk
This is an interesting thread so I contacted my old friend, Mr Google Interwebs, to see what he had to say. It seems "flash chrome on stainless" is a real deal but it was used more in the past for auto trim cosmetic reasons than it is now. It is used for all the other reasons mentioned, too. It's still commonly used for the hardness benefit.
this is flash coated stainless trim from a 63 Lincoln, the trim was supposedly repaired and chromed. It is a friends car and he brought it in the shop for me to rework it before he gets it rechromed. Sent from my iPhone using The H.A.M.B. mobile app
that is interesting. i had hood hinges for a '65 jeep tuxedo park, replated. the plating peeled off. when i asked the plater he said the hinges were stainless and chrome does not stick to it. he replated them and they have held up so far.
Well if it is chrome, they didnt use any copper over the stainless, and it is very thin and can be feathered.
I spent the better part of last weekend polishing stainless trim on a '61 Olds 88. I didn't find any coating on the stainless. I started off with the pieces that go on top of the doors, and the ones on the pillar posts and under the roof. Some of the dullest pieces I had to DA with #800 and #1000 before using two rouge compounds to get the shine.
I tried the muriatic acid, it didn't do much of anything, so I painfully sanded it all off, then it polished up nicely. The side trim doesn't have the coating.
Sure looked like anodized aluminum in your pics. Did it polish up like your other stainless? Harbor freight has a set of diamond impregnated rubber-like 4" wheels that work great on stainless when you have a lot to remove. I just use the two or 3 finer grits in the set when I had a bunch of pitting/road rash to remove as you would find on the forward facing trim pieces. It will get you a good start prior to the final sanding/buffing without adding additional scratches to get out.
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