I finally found the picture I was looking for. Looks like they were chrome on the wire wheels. Lew Clark was the tech advisor for 29 for many years I would bet his car was correct.
Actually the 1929 wheel nuts were zinc plated. Same as the earlier rims and other steel parts. You will find them listed as galv. in some period documents.
Thanks. If I am seeing it right in Lew's picture the nuts are not as reflective as the caps which would support zinc or cad. Synder's Ford parts has a couple of choices and the Cad plate is what they say is original on their cars. They look just like my rusty ones as far as shape have you seen those?
The problem with cadmium plating is that it is just not as long lasting as zinc in wet environments, such as wheels. Electroplated zinc is generally not as thick a coating as dipped. Finding a zinc plater in todays business environment can be a challenge.
Actually the 1929 wheel nuts were zinc plated. Same as the earlier rims and other steel parts. You will find them listed as galv. in some period documents.
I certainly defer to Chipper. Zinc plated rather than black. Now I have six cars with the wrong color wheel nuts. Now what? I hope somebody will send me 146 zinc-plated nuts. 144 for the cars and two for me.
On all the old photos from Chevrolet (and also one from MGM) that I have the lug nuts appear light, the same as the hub caps. I assume they were plated, even though all of mine had no sign of plating on them.
It is to be expected to have original lug nuts to have the plating at least mostly gone in 90 years. To determine what was done by folks that are surely now on their last assembly line makes the research a little more difficult. The fact that they left some photographs (a few without artistic enhancement) can be good clues in the search.