PAINTING MAGNESIUM WHEELS

Some paint info here:

http://stevekouracos.com/resto...m-wheel-restoration/

Nothing on annealing though.

This month's POCA newsletter has a good article on the subject of magnesium wheel reconditioning, and addresses both paint and powder coat.

It seems to me that two experts are Bosswrench and Larry Stock.

I media blasted, annealed and painted a set of Pantera wheels, they came out nicely. It didn't seem too hard.

Rocky

The stevekouracos wheel restoration link suggests using Alodine to coat magnesium wheels. Alodine is a process for aluminum - it is NOT recommended for magnesium and does not satisfy MIL-spec requirements for the treatment or protection of magnesium parts.
http://stevekouracos.com/resto...m-wheel-restoration/

Magnesium wheels need to be annealed to relieve the stresses they store up. Cooking them in the powder coat oven is actually beneficial. The only detriment is if they have not already been annealed before powder coating, the out-gassing of the magnesium may cause bubbles/craters in the powder coat finish.

I restored my wheels once following a process similar to Steve Kouracos, but used the correct zinc chromate primer from Aircraft Spruce. However, I was dissatisfied with the durability of the finish - might be fine for a seldom driven Dino that only sees an occasional car show, but I DRIVE my car!

Here's how to anneal your Campy wheels:
http://www.poca.com/detomaso/2000-06/1205.html

Anyway, as I mentioned I was dissatisfied with the durability of the Eastwood Argent Silver paint on my wheels, so I decided to powder coat them. You can see the results here:
http://pantera.infopop.cc/eve/...081069456#4081069456

Powder coat is much more durable than traditional paints and seals the wheel against moisture.

And to answer your next question about color, here's some additional info.

The correct color
Ford TSB, Bulletin #11, Article 92.
Service Paint - Magnesium Wheels Color: Argent Silver
Ditzler Part No.: DX8555

HOWEVER, when I first restored my wheels, I couldn't find that paint from any local supplier - it's an obsolete number with no current cross reference. However, I've subsequently been told that the old Ditzler color code DX8555 cross references to a new color code: DAR33772 Silver Poly.

Note: The following info is from a Chrysler board as they use the same paint code for various parts. The Light Textured Argent, part number DX 8555, is obsolete. Medium Textured Argent, part number DNA 8933, can sometimes be found at larger, older Ditzler dealers. Last used in the mid 1970's, it is now all but obsolete. Older Ditzler dealers that have remaining stock can mix this paint for you, but it can also be mixed from currently available paints. Here's how...

LIGHT ARGENT TEXTURED
Ingredients for 1 pint (double for quart)

• 1/2 ounce DX 204 - Radiance Silver
  
• 1/2 ounce DDL 8568 - Non Smudge Aluminum/aluminum base
  
• 3 1/2 ounces DCA 468 High Performance Clear
  
• Add 4 ounces of top grade lacquer thinner with drying time according to temperature. Mix thoroughly and pour in 1 pint touch up gun. Use 10 clean 1/4" ball bearings in paint cup to keep the paint mixed. Use three light coats over an existing finish or four to six coats over unfinished parts. This paint runs VERY easily, allow 5-10 minutes between coats.

MEDIUM ARGENT TEXTURED
The steps are exactly as above, but add black lacquer to darken. Start with six drops per pint and stir thoroughly, then spray a sample to compare to the original finish. Add a drop at a time until you achieve the correct tint. Spray these paints at 55-60 lbs. keeping the gun 18-30 inches from the surface. Frequently agitate the mixture to maintain uniform consistency because the Radiance Silver is heavy and will settle out quickly. Also, Year One sells part #QP323, which is Chrysler rally wheel paint, and part #QP8575, which is the textured light argent silver paint used on Chrysler grilles and rally wheel center caps. Both are sold in quart cans.

Plastikote Spray Paint
A fellow club member used Plasti-Kote "1001 Bright Silver Metal" in an 11 oz. spray can and reports that it was a good match, and an economical option for repainting original Campys! The label on the can said "Plasti-Kote Body Shop Paint, for Painting Doors, Fenders, Hoods and Other Large Panels on Cars, Trucks & Vans". This paint seems to be very forgiving when it comes to runs and sags, and giving a run a little more spray seems to make it lay down smooth.

Technique: You need about 60 inches of 6 inch wide aluminum flashing - comes in a roll at your local home improvement store. Unroll the flashing and form a ring that just fits outside the wheel rim and snugly down onto the tire. The wheel needs to be off the car and laying flat on a piece of newspaper or cardboard to keep the floor or driveway from turning silver. Clamp the ring with a pair of vice grips to hold it to the correct diameter. Don1t worry about the flashing over lapping itself that usually helps it hold it's shape. Mask off the valve stem and spray away.

Note that Plasti-Kote also lists an Argent Silver (#621) on their website, but I have no idea if it's close to the color we need for Campys; it might be worth getting a can to test.

Eastwood Light Argent Silver
I used Eastwood's Argent Silver then coated with Eastwood semi-gloss clear to facilitate easy cleaning. My Campys looked perfect. Others have misted with Eastwood's Cad Silver between the Argent Silver and the semi-gloss clear for a "perfect" finish, but I found the light argent silver straight from the can looked pretty near perfect, especially when coated with Eastwood Diamond Clear (satin finish).

FWIW, I invested countless hours annealling the wheels and doing all the dirty work cleaning and stripping them, and spent about $200 on the stripper, Zinc Chromate Primer, Eastwood Silver Argent and Diamond Clear paint.

Cardinal Silver Metallic 30% Gloss Powder Coat
As I mentioned above, I was disappointed in the durability of the rattle can paint from Eastwood, even though it's a premium paint. I suppose it's easy enough to touch up, but I wanted a more durable solution which is why I powder coated my wheels.

The color I used was Silver Metallic 30% Gloss (T353-GR06) from Cardinal Paint and Powder. It's a pretty darn close match to the Eastwood Argent Silver (and the original color!), but I wouldn't say it's a "perfect" match. Although, close enough for me! Eastwood offers Argent Silver Powder paint, so theirs might be a perfect match.

The only drawback to powder coating in some opinions is that if applied too heavily you can get a "coated in plastic" look to the finish in areas of fine detail. In the "close up beauty shot" at the bottom of the first page of the powder coating thread you can see some of this effect around the cast "Campagnolo" name.

Thanks Garth for that information.

I am told that magnesium wheels have significant aluminum alloy in content to prevent them from being too brittle. Annealing is another question supported by some and not by others.

Thanks again, I will let you know more but powder coating seems the way to go.

Dick Ruzzin

Dick,

The important thing to do, when dealing with magnesium and powder coating, is two fold.
1) use sealer on the wheels. Powder coaters should know about this! (Any that have done mag!)
2) Annealing.....COOL DOWN must be last job of the day, and sign an agreement with the coater that they do not expose the wheels once baked.....leave them sit in the oven over night to cooooooool. As slowly as possible, or you can reintroduce stress into the metal.

You may be able to get the job done on a holiday weekend...where they can spray them and let them sit while the oven is turned off and cools over a 3-4 day holiday.......that would be ideal in my books!

I used some sort of a BMW metallic silver rim color that my coater had used prior. Close to original but with some zing (bling?) to it? They look really nice.

The powder coater fought with the outgassing AND porous castings with my wheels.....so don't be surprised if they clean off the wheels and find the surface of the moon! Once they got the craters filled, AND they used a proper sealer for the powder coating things went much better!!!

Good luck!
Steve

This may sound silly but what should I use to clean the in board side of the wheels of the brake dust and crud build up? I just don't want to put a cleaner on that may screw something up.

I like using good ol' soap and water on refinished wheels....and perhaps some scotchbrite pad if the finish is already toast......

As for anything more aggressive, check the label and see if there are any interactions listed for magnesium!

I wouldn't think that normal wheel cleaner for getting brake gunk off would be a problem, but sometimes these do damage paint...hence their warning to test some place inconspicuous!!! But you have to consider that they use this stuff at the car washes on clear coated wheels...... it's the wheels where the paint/clear is worn off or just plain isn't there!

WD40 also works great for greasy blobs etc......!

Good luck! PITA job!!!!!

Steve

Thanks Steve, it is a PITA job. I was thinking of using engine gunk cleaner but will try the WD-40 first.

I also suggest that if you're going to such extremes to fine-finish your Campys, go the extra distance and get rid of those rubber valve stems! Rubber of all kinds deteriorates with time, sunlight, smog/ozone exposure and weather. They crack and are the single most common reason these days for sudden tire deflations.

Metal valve stems are insensitive to all the above. Pantera vendors carry chromed-brass stems in various lengths (shorter is better) and a few carry the factory-optional Gr-3 aluminum valve stems with aluminum caps. Doesn't save much weight and you do need to use anti-sieze on the stem-nuts and caps. But every little bit of unsprung weight-loss helps handling. and they are 'factory'.