Magnesium Early Weber Manifolds- Plating Step #1- FLASH COPPER

Wow. . . .check this OUT. . .

911 Weber manifolds are magnesium.

The early ones received an iridescent yellow-blue "chem film" or other surface treatment. I have posted some photos of what they looked like here. The later ones were coated with a black "imron" which is extremely durable.

Replicating the early coating is not only hard to do in terms of the color, but it's also a good idea in terms of preserving the magnesium- 40 years of moisture and corrosion have taken their toll on the original surface, which is revealed after the manifolds were ceramic tumbled and surfaced.

Anyway, here's the issue- you can't just Cad-plate magnesium manifolds using the same process you use for steel-- the first step in the plating process is a "strike" or acid dip to activate the substrate, then the plating starts. Unfortunately, if you dip magnesium in the acid. . . it will go away! The plater wouldn't even take these the first time around.

Turns out you can plate the magnesium with an alkaline process that doesn't dissolve it-- you plate with either flash copper or electroless nickel. Then you do the cad/chromate process normally. Flash copper is the best substrate, so that's what I did.

This whole process was done at Millenium Plating Company in Lowell, MA.
Their contact information is below. Please tell Steve you heard about this process through the Early 911S Registry.

Millennium Plating Company, Inc.
75 Phoenix Ave.
Lowell, MA 01852
(978) 454-0526
(978) 454-0915 FAX
sales@magplate

Steve can also do the other mag parts. . fans, blower housing, magnesium valve covers, etc. I'm going to do the fan for my race car in Electroless Nickel. . . not only will this look great and be easy to keep clean, the abrasion reistance will be extremely good.

OK, time for the photos. . . . are you ready? I included the original shot to show what these will look when they are done.

Price for mag plating is available from Steve, it's not inexpensive, something like this is around $200.

I've closely inspected both sets on my '67Ss during engine rebuilds and haven't noticed any coating? Neither had any corrosion whatsoever (both are clean West Coast cars). They have not been blasted or handled in any way, just washed in the parts washer, and then oiled. I could post some photos later.

Many magnesium parts received a DOW7 process. It gave the magnesium a gold to brown color. It was also used on the early 911 fan housings and fans. Basically, DOW7 is a chromate conversion process done specially for magnesium. It wears off pretty easily so you do not see remaining on parts unless it is hiding under a washer or on a mating surface.

Quote:

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Originally Posted by Brad Davis

Many magnesium parts received a DOW7 process. It gave the magnesium a gold to brown color. It was also used on the early 911 fan housings and fans. Basically, DOW7 is a chromate conversion process done specially for magnesium. It wears off pretty easily so you do not see remaining on parts unless it is hiding under a washer or on a mating surface.

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You're right, Dow 7 was used on certain magnesium parts, but more likely in the racing department, as it leaves a brown coloring. You can see it on these magnesium engines-- Carl Thompson's 917, and one of Armando's factory 906 cases (you can see the repair where a rod punched a hole in the case, presumably).

What is on these manifolds isn't Dow 7-- I also tried the Henkel "magnesium refinishing kit" which is a very expensive process- basically a chromate. The trouble is, just applying the chromate over the top of the magnesium does not produce the bright finish-- after a lot of research, I don't think it was a ferric nitrate bright pickle, nor is the finish "iridite" or any of the presently available magnesium coatings.

Someone was kind enough to post images of the original Dow Magnesium treatment process-- a whole book of them. . . unfortunately many of these require laboratory conditions and processes that just aren't commercially available today, or involve toxic stuff that I don't have interest in going anywhere near.

The chromate step following cad plating should replicate the factory finish, I can't wait to see how they turn out.

Quote:

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Originally Posted by tfiv

I've closely inspected both sets on my '67Ss during engine rebuilds and haven't noticed any coating? Neither had any corrosion whatsoever (both are clean West Coast cars). They have not been blasted or handled in any way, just washed in the parts washer, and then oiled. I could post some photos later.

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Look very carefully at the flanges and the runners adjacent to the flanges-- you will see that these are a different color than the rest of the manifold. This is because the factory first used a chemical film on the manifolds, then surface-ground the flanges and faces on both sides to true them up.

What is the serial number of your Webers? It's possible that the factory discontinued the coating after a while-- mine are some of the earliest Weber manifolds out there (my car was produced on April 1, 1966 and the Webers were introduced in February, 1966) so there may be undocumented differences. The exact date of the transition to black "imron" is also in question.

I've never had any luck trying to reproduce the light gold iridite finish, and have always defaulted to the Dow 9 black finish like the 917 valve covers. The brown just doesn't look right to me. Are the copper finished manifolds done yet? Gordon

Do you have finished photos of the flash copper plated intake manifolds?

http://www.early911sregistry.org/for...missing+engine