How to "color" the magnesium parts?

[Elferhelfer]

Dear all,
I could need some help fort he correct treatment of Porsche magnesium parts,

How can you recolor for example the 911 fans correctly? Perhaps you hav esome ideas for DIY processes. It would be great, if you could help with the DIY procedure. I’m based in Europe and looking for the correct finish of magnesium parts and aluminium parts like intake manifolds, fans, valve covers… Actually I have media blasted several fans and mangesium parts and I would like to recolor them like in the factory, or close to to this finish.

Moreover I have seen dark grey and black „coloured“ parts of Porsche.



How is it done, how is it treated... I heard about already about Alodine processes, especially from Henkel, but I’m not sure, if it´s the right one...

It would be great, if you could help me!

Best regards
Florian

[Ivan Fuller]

Alodine should give you nice gold if the metal starts shiny - the look everyone says is impossible. Takes some expeimentation.

[RSTarga]

Aldine is for aluminum, the factory used a chromate dip for all the magnesium.

[Ivan Fuller]

Years since I did it but and I may be corrected but alodine is chromate based as well, and the VW case above was done with alodine - was on there 5 years that I owned the car and still looking good.

[718RSK]

Actually I have media blasted several fans and mangesium parts and I would like to recolor them like in the factory, or close to to this finish.

From my experience this is a big no no if you want the parts to have the same radiant sheen as they had when they were new after the chromating. I did some parts for my 4-cam engines years ago and the ones I just degreased came out real nice, the blasted parts less so. In addition the type of magnesium alloy, its age and the number of heat cycles the parts has endured also have an effect on the final finish I have been told.

[RSTarga]

Alodine is a brand name so they might have products for both Aluminum and Magnesium. The chromate finish on magnesium gives a dull grey look, the gold comes from the waxy protectant on top.
If the raw magnesium is not neutralized with chromate, it tends to oxidize quickly and gets that chalky look. There has been a lot of discussions here on how to redo the fans so a search might find the correct products.
I've used alodine on aluminum and it gives that goldish tint. I bought the dupont product at an auto paint store. I used to have the link for the mag chromate but can't find it.
Is that generator support on the VW magnesium or aluminum? I think the block is magnesium, but I bet the support is aluminum.

[RSTarga]

This is my chromate fan and housing:

[304065]

What you are seeing on those chain boxes is "Dow 7." That is not the same as the chromate used on Solex and early Weber manifolds.

[37yrold911]

for the fan and fan housing, I prefer a surface treatment known as "motshagenizing"

[RSTarga]

He does great work, but not the original process.