Hot Rods magnesium finish

More Dow #7 info pulled from http://www.chemical-supermarket.com/Dow-7-Magnesium-Treatment-Compound-p652.html

Chemical Name: Dow 7 Magnesium Treatment Compound
Synonyms: Dow 7

Product Description:
The Dow 7 magnesium treatment compound is provided as a pre-
mixed powder that is dissolved at time of use in 4 gallons of water.
This will produce enough solution for a 4-gallon immersion bath.

The complete process will require the initial activator solution which
is available as either Type I or Type II. Scroll down to the “Related
Products” section below to see the activators and description for their
proper selection which is alloy dependent.

Introduction:
Magnesium and its alloys are more galvanically active than even zinc
on the galvanic series. Magnesium will form a strong galvanic cell with
every other metal it comes into contact with and is always sacrificial.
When magnesium corrosion is detected, it requires immediate attention
or the corrosion will spread throughout the entire structure. Therefore,
these alloys must be properly protected from corrosion damage.

Background:
Dow 7 is a good choice for both new and overhauled parts that have
dissimilar materials such as inserts, or where conditions will tolerate a
less robust and less costly alternative to Dow 17 anodizing. It makes
an excellent paint base and provides the best corrosion protection of
the available chemical coatings for magnesium.

Dow 7 is a chemical conversion coating which results in no appreciable
dimensional change to the component. The surface of components coated
with Dow 7 is changed to a brassy or dark brown finish depending on the
alloy. Note that this coating film is dielectric (non-conductive).

Process Description:
The complete process requires two steps. The first step is an activator
immersion which is done at ambient temperature in the range between
70ºF and 90ºF. This is followed by a distilled water rinse.

The second step will require a stainless steel vessel that will allow
the heating of the Dow 7 solution to boiling point (200ºF). Immersion
time for the parts is about 30 minutes, also followed by a water
rinse before allowing to hang dry for 24 hours.

 

I really believe it is nickel plating , I put a polished alum part up against my windshield frame (nickel plated) and the results are the same as the pics of the wheel

 

Chuck is correct that magnesium is the most active anodic metal. When corrosion is detected, immediate action must be taken. Chromic acid can be applied to resist corrosion, it also provides a bond for other coatings to resist corrosion. This will give a golden or light brown color to the metal. unsure if you could polish the metal then apply the coating to get the look you are after.

Google "Spec MIL-M-3171, type IV". Additional info, FAA AC 43.13-1B Para 6-148 thru 6-152. I tells you how to repair, remove corrosion, and treat to resist corrosion.

Good luck, Mark

 

thanks for the input guys! much appreciated!!!

 

Personally I like natural oxidation

 

This is an example of why one should never patent anything. You are giving away your secrets to anyone that wants them. They can start a company using your idea to make lots of money then fold the company in bankruptcy if you can afford to defend your patent and win.

 

Some good info. Looking forward to hearing what's drummed up.

 

Interesting the twitter that a good add man and a little fib ( or lack of an honest description) will produce. These are nickel plated aluminum wheels. They look great for the rich instant gratification guys, but will look like hell after 15 years in a shed on the Gulf Coast.

 

Redo32, so if I'm in the dry socal desert, can I expect 20 years?....that would make me happy

 

We do tons of mag at work. We rebuild and overhaul heavy lift helicopters. The finish you are looking for is a trichromium pickle solution. It is easy to make but getting trichromium is not super easy. You mix it with water and plaster of Paris.

The concentration of the mix will effect the color of the part, from yellow gold to deep black. It will also eat and convert any existing corrosion.

It is also pretty toxic.

 

So what is this that you speak of ,

These are nickel plated aluminum wheels


Is there a pic this statement referees too ?