Many fasteners/parts were originally plated black phosphate. I've heard that folks get originally phosphated parts replated during restoration with black zinc as the appearance is similar, but durability is much better.

So if you put a phosphate plated part next to a black zinc plated part could you tell them apart?

going black zinc sounds appealing based on its durability.... howeover, i have never seen side by side comparisons. I am looking for the best of both worlds....looks 'correct' and durable.

Thoughts?

Black zinc doesn't always look black. Here are two pictures from iccahome.org Both are black zinc.

http://mmcdetroit.com/ICCA/References/Plating/Black_Zinc/image_02.html

http://mmcdetroit.com/ICCA/References/Plating/Black_Zinc/image_01.html

Black phosphate looks nothing like black zink plating. Orig black phosphate is a non shiney greyish black coating. Black zink is a plating and does have a better corrison resistance. If you store your car outside use black zink. BTW, the kit from Eastwoods is not black phosphate and offers no real corrison protection.

Black zinc tends to be smoother - thus shinier than black phosphate.How the part is prepared will also change how the finished part looks.

BUT,
(And this applies to any kind of zinc based plating)
But the depth of color will vary greatly with the age of the plating solution AND how long said part is immersed in said solution.

As an example.

Beepbeep did a test a few years back with yellow zinc di-chromate. Which by all standards is yellow/gold colored with a multi colored rainbow look to it.

Essentially using multiple pieces he left some in longer than others. And the longer it was left in the solution the darker the parts would get with the last ones removed coming out almost black.
But I don't remember how long each particular piece was left in.

As an example
Black zinc on the left
Black phosphate on the right

thanks for responses.

how much corrosion resistance is afforded by phosphate?....on a car that won't see rain and will be stored in a non climate controlled garage

What is the correct finish for the hood latches and catches?

Typically platers in the business call Black Phosphate... black rust!
It does not offer a long term rust resistant solution.
Black zinc will last longer and perform better if parts are left outside longer.
Many conditions come into play when deciding on longevity.
If your car will never see the light of day , then black phosphate will last long.
Depending on the year and car, most latches are brown zinc or antique zinc.
Jules

Phosphate will last longer than you for what you are going to do with it. Other than the maybe being worn looking are the parts you needing done rusted away? I doubt it and they are 40+ years old. Pending on your final plans for the resto either type is fine just dont let phosphate being not worthly kid you.

Eric