1962 License Plate Lamp Assembly

[Bill O.]

Need your help.

The TIMJG says this housing should be "zinc plated".
When I removed mine today to begin a clean-up, it looks like it is yellow/gold cad plated.

Can you say whether the yellow/gold tone is correct for this application and if both Cad and Zinc plating can produce a yellow/gold appearance?
If so, I assume it really makes no difference as long as I get the correct tone.
You can see I know little.
Thanks for any help you can provide.

Bill

[Joe L.]

Re: 1962 License Plate Lamp Assembly

Need your help.

The TIMJG says this housing should be "zinc plated".
When I removed mine today to begin a clean-up, it looks like it is yellow/gold cad plated.

Can you say whether the yellow/gold tone is correct for this application and if both Cad and Zinc plating can produce a yellow/gold appearance?
If so, I assume it really makes no difference as long as I get the correct tone.
You can see I know little.
Thanks for any help you can provide.

Bill

Bill-----


First off, let me say that I don't know much about the 1962 license plate lamp assembly.

However, bear in mind that any part that is zinc or cadmium plated can receive an irridite overplate. This chromic acid-based process is what imparts the "gold" color. Without the irridite dip, either zinc or cadmium is silver in color with no or virtually no gold coloration.

If the original license plate lamp assemblies were zinc (or cadmium) plated and received no irridite dip, then they should appear silver in color. It is possible that later SERVICE lamp assemblies were irridite-dipped, though. I've noted a fair number of metal parts that were originally silver zinc or cadmium with later SERVICE parts (sometimes also used in later PRODUCTION but not in this case since 1962 was the last year for this assembly) having the irridite dip. So, it's possible yours was replaced previously. 48 years is a long time for replacements to have been needed and effected.

[Jack H.]

Re: 1962 License Plate Lamp Assembly

EXCELLENT tutorial!

The use of chromatic acid to dichromate cad/zinc parts for improved oxidation resistance WAS a learning curve technique. Joe's quite correct in saying service replacement parts are more prone to having the extra gold tone dip than earlier factory original parts (depends on year and the specific part).

The final gold finish on zinc/cad parts so constructed is VERY thin...just enough to fill the surface pores left from the original zinc/cad plating. So, if you have a service replacement era part that's been dichromated, it's child's play to remove the gold tone.

Just buff it LIGHTLY and watch the gold 'evaporate' leaving the underlying silver finish of the native zinc/cad plate...

[Bill O.]

Re: 1962 License Plate Lamp Assembly

Thank you Joe and Jack.

Because the housing has all the GUIDE info impressed, it must be a service replacement. AND I had started removing the gold finish, after reading Joe's post, with lacquer thinner with some success. Now I'll shift to buffing. I turns out quite usable as the cad/zinc finish underneath is in great shape. Finally, I'll repaint the exterior portion black and install the WHITE gasket with the lens, which is where this Odyssey started.

Thanks again for the help.

Bill