Pre War Buick hardware restoration question

[MCHinson]

My 1937 Buick Century is, to the best of my knowledge, a Survivor although it has had a lot of work over the years. I don't think it has ever been totally restored. I have tried to do any maintenance with the thought of maintaining its appearance or if improving it, making it look more like it did originally instead of different from how it was produced. Although I write up a lot of work that I do on the car as the editor of the Torque Tube II for the 36-38 Buick Club, I realize that I am not an expert and I never claim to be an expert.   

 

I have seen others restoring cars using several different approaches to restoring hardware such as nuts, washer, bolts, etc. I have seen some people painting hardware black, some cleaning it up and coating it with a clear protective film, some using chemicals similar to gun bluing, some cleaning them up and leaving them as bare steel. I realize there are probably some different approaches that I have not listed or thought of. Being born in 1960, I don't have a good reference on how hardware manufacturing finishes were typically found in 1937 or 1938. I do remember the appearance of bolt, washer, and nut finishes that I saw in boxes of new hardware in my father's machine shop in the early 1960s. 

 

Sometimes my parts manual shows part finishes for bolts or other hardware. Sometimes it does not.

The bolt descriptions that I see in my chassis manual include the following text regarding finishes:

 

Plain

Cad.

C.P.

N.P.

C.P. (Brass)

 

I assume "Plain" indicates unfinished plain steel. I assume "Cad." indicates Cadmium plating. 

 

If things go as planned,  I will soon have a 1938 Buick project that is in need of a restration. I would be interested in any information from those engineers, original car owners, and other experienced individuals who can offer an idea about themeaning of these different finish descriptions and the best way to restore or replicate those finishes today. Any best practices for restoration on hardware with undocumented finishes would be appreciated. 

 

 

[Mark Shaw]

I suggest that most logically; C.P. = Chrome Plated, N.P. = Nickel Plated, and C.P. (Brass) = Chrome Plated Brass.

[25 Buick]

You can coat bolts black iron finish instead of natural finish. Or painting

[MCHinson]

8 hours ago, Mark Shaw said:

I suggest that most logically; C.P. = Chrome Plated, N.P. = Nickel Plated, and C.P. (Brass) = Chrome Plated Brass.

 

Thanks, That would be my best guess as well. Thanks. I need to do a bit more research on individual items in the chassis manual to see what items had which plating. This could be a very involved process to try to restore all of the hardware correctly.

 

I am thinking that for long term protection, perhaps a black oxide finish would be the most logical current choice for those that were originally plain. Any other opinions or suggestions?

[DonMicheletti]

If you are careful when removing bolts, you can get an idea of their original condition, providing they are not badly rusted. Usually there is some trace of the original condition under the head.

On my '38, bolts that appeared to be "raw", after degreasing, I'd put them in a cheap vibratory deburrer with some sand in it and let them run for a couple of days or until they looked clean. They come out with a slight matte finish.

Then I would spray them with a clear matte finish lacquer. They would end up steel looking and not too shiny.

 

The fact that I got my '38's 40+ years ago and they were garage kept and totally rust free was a big help.

[MCHinson]

Thanks. I don't think my project car is going to be in very good condition. It was a good running car that through a series of unforunate events has been stored outside up north for a long time. I am looking forward to the project but I am a little bit worried about what it is going to look like when I actually get to see it in person.

[DonMicheletti]

Ouch! Than can hurt.  Good luck.