Stainless Polishing

[John H.]

Re: Stainless Polishing

There is no such thing as "Flash Chromed" stainless from any GM plant. This is just a rumor started by some novice or a joke!
Lets talk about the chrome process for a moment:
All bumpers and exterior brightwork is prepared first by stripping to the bare steel sanding, buffing and then applying copper. The copper is then sanded and buffed. Nickel is then applied at a very high cost relative to the chrome being much cheaper. After the nickel is applied the part is then "Chromed for approximately 15 seconds. If you call that "Flash Chromed" then ALL bumpers done by a competent Chrome Shop are "Flash Chromed". If prepared properly before the chrome is applied there is very little chrome on the bumper.

JR -

We're talking about the original GM process, not the triple (copper-nickel-chrome) "show-chrome" process used by outside/aftermarket platers. GM didn't use copper as a plating base (except for some Cadillac applications) - GM "factory chrome" was nickel on a bare steel base, then (clear) chrome .0002"-.0004" (that's ten-thousandths, not thousandths) thick to protect the nickel from oxidation. A good friend of mine was the Production Manager at Chevrolet-Livonia Spring & Bumper, where ALL Chevrolet bumpers were made, and I witnessed that entire process several times in the late 60's.

GM factory stainless exterior (and most interior) bright polished trim moldings were "flash-chromed" (also called "smack-chromed") after stamping and polishing to protect the stainless substrate from oxidation/dulling. Most of these parts were made by Fisher Body or by Ternstedt Division, and every Fisher and Ternstedt plant had its own chrome plating line for flash-chroming stainless parts; I witnessed several of those Fisher Body flash-chrome plating processes too (specifically on windshield and backlite reveal moldings).

Don't confuse aftermarket/restoration plating practices with the original GM factory plating processes - they're different.

[Rich C.]

Re: Stainless Polishing

Soooo...that brings us back to what would be the most accurate method of refinishing stainless trim thats not beat up just a little dull. Would I be risking damaging this 'flash chrome' by polishing it? And again did this process continue into the mid '70's up to the time that GM started 'blackening' the trim?

1973 LS-4 454 coupe owned 24 years
1996 LS-4 CE coupe owned 6 months

[John H.]

Re: Stainless Polishing

Soooo...that brings us back to what would be the most accurate method of refinishing stainless trim thats not beat up just a little dull. Would I be risking damaging this 'flash chrome' by polishing it? And again did this process continue into the mid '70's up to the time that GM started 'blackening' the trim?

1973 LS-4 454 coupe owned 24 years
1996 LS-4 CE coupe owned 6 months

Rich -

Tracy Crisler is the best guy to answer this, as he's been repairing/polishing stainless trim/moldings for many years. However, if you're going to polish stainless, you first need to remove the (clear) chrome layer - Tracy has described that in previous posts.

[Timothy B.]

Re: Stainless Polishing

On my 63 top shield we buffed through the flash chrome in one area. It took a serious buffer and some pressure but I can attest it's flash chromed over the stainless.

[Paul J.]

Re: Stainless Polishing

Rich, the chrome layer is very thin. If you polish it you will wear through. As John mentioned, you need to remove this layer and have the piece flash chromed when you're done polishing. If you don't chrome it, it will appear yellowish after a while when placed next to chromed pieces. There are several threads about this in the archives.

Paul

[Tracy C.]

Re: Stainless Polishing

Rich -

Tracy Crisler is the best guy to answer this, as he's been repairing/polishing stainless trim/moldings for many years. However, if you're going to polish stainless, you first need to remove the (clear) chrome layer - Tracy has described that in previous posts.

wowzer...thanks John, I'll get your 5 bucks in the mail Monday morning..


Rich, As described, Think of the flash chrome as nothing more than a really really hard layer of clear over the nickel or stainless. Because stainless has enough nickel content, it was never nickel plated, Just polished and smacked chrome plated. This plating is less than .0002 thick, You can buff thorugh it with agressive polish, but it is easier to chemically strip.

There are several posts in the archive on stainless polishing. Once you get the hang of it, it become addictive turning "so-so" trim into jewelry for your car. You really need to send it out for flash chrome when finished or all your hard work will oxidize and turn yellowish after 2 or 3 years in the elements.

tc

[Terry D.]

Re: Stainless Polishing

TracyWhat do you use to strip the old chrome and how do you know it is all gone? Thanks

[John M.]

Re: Stainless Polishing





Note: If you over-polish the stainless and then re-smack it with chrome, the finished product will/should be of higher quality shine than originally as it came off the assembly line. With how anal some judges get about paint finishes I wonder how this will go over with them?

[John D.]

Re: Stainless Polishing

I have decided to polish trim myself. I found a kit from Eastwood for $100 that includes a 1/2 HP motor with 6" buffing wheels and supplies. Does anyone have any experience with this kit and would motor be the appropiate fit for my job?

Be very careful Walter. Doesn't take much when polishing SS for the buffing wheel to grab and throw the part 100MPH.

M&P Refinishing does a ton of buffing of SS. They are also an excellent chrome plating shop and specialize in pot metal. www.mprefinishing.com
Talk to the Kerlin brothers. 724-527-6360 Excellent work and a rather fast turnaround. JD

[Walter R.]

Re: Stainless Polishing

Sorry it took so long to get back. I have only done a few pieces but am pleased with the buffer. I don't know what will happen with time but we'll see. With so much information available I think I'll only be able to judge it after a period to see if it holds up. Glad I purchased and went this route.

[Jack J.]

Re: Stainless Polishing

Cadillac Motor Car Division had their own in-house plating department, with huge tanks spread out on the ground floor, with buffing,polishing on other floors and buildings. Three step plating process-copper, nickel, chrome. Undoubtedly,the best in the auto industry. All front and rear bumpers received the 3 steps. Also, numerous small parts- grills, trim pieces.