Screw plating

[Erich]

As a rivet counter, I'm wondering about the plating used on things like the EA Sports. For instance on the engine side panels. I realize that today, including on my Rep, there are stainless screws. Originally, what would have been used? Cad plating was the norm on motorcycles. Did Austin use this, or regular zinc, or just paint and accept that they would start to corrode?

Erich In Seattle

[David.H]

As a rivet counter, I'm wondering about the plating used on things like the EA Sports. For instance on the engine side panels. I realize that today, including on my Rep, there are stainless screws. Originally, what would have been used? Cad plating was the norm on motorcycles. Did Austin use this, or regular zinc, or just paint and accept that they would start to corrode?

Erich In Seattle

Erich
As I recall Cad was widely used because it's corrosion resistance was very good, despite it being relatively soft, and it also has good lubricity. I do not know if passivation (yellow or clear) was used pre-war. It went out of favour because of the toxic properties of Cadmium, except in the Aircraft industry, where it's superior corrosion resistance is considered to outweigh the dangers of people sucking on screws ! (Flippant comment, the real problem is handling/disposing of plating effluent etc & Platers who do Cadmium are few & far between & heavily regulated.
Some fasteners were often simply chemically blacked & varnished, which is just about ok inside a car, but doesn't last long outside. Other finishes were phosphating or even Sherardising, but I think they probably became popular during or post war, but someone may know better than I.
Cadmium is very good when used with aluminium as the electrical PD is negligible compared to zinc and it is very good at "self healing" ...especially compared to modern fastener's finishes which have superb corrosion resistance....as long as the coating stays intact!

[Erich]

Thank you, David. I had thought that cad was likely the plating used. Fortunately, in my case there are several very good plating companies near me. Boeing's Everett plant is less than a mile away and one of the local platers I have used for decades has plated fixtures on Air Force One and the Sultan of Brunei's jet.