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Powder Coating Campy Wheels at home

garth66garth66"When speed is the only thing that counts"
Just a few pics of my project this past weekend - powder coating a couple of wheels.

First of all, I already annealed my wheels following the procedure described in this thread:
http://pantera.infopop.cc/eve/...660097094#1660097094

Then I sanded and/or bead blasted them to thoroughly clean them. Any "curb rash" or missing chunks from the edge of the rim were filled with JB weld and filed and sanded to shape. It's not uncommon for these wheels to have chunks missing due to tire shop monkeys mounting clip on weights to balance the wheels - and often to remove such weights they grap them with pliers and rock back and forth and break off a piece of your rim. I can't tell you how many rims I've seen damaged like this. Anyway, one of my wheels had such damage - unfortunately I forgot to photograph the damage and the repair.

My powder coating equipment consists of the cheap ($59) Harbor Freight Powder Coating kit, however I used quality powder paint purchased separately (I read on some powder painting forums NOT to use any of the Harbor Freight powder paint).

Anyway, here are the pics... This is my makeshift spray booth with home made lazy Susan to spin the wheel while spraying it.

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garth66garth66"When speed is the only thing that counts"
The reason for doing this... I previously restored my wheels using Eastwood Argent Silver and satin Diamond Clear which yielded excellent results, but has proven to be less durable than I would like. I suppose it would have been easier to just mask off the tire and apply another coat of the Eastwood paint, but I've been very pleased with my powder coating results on various engine brackets and my coolant tanks, so decided to try powder coating my Campys.

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garth66garth66"When speed is the only thing that counts"
Since my oven is a basic household oven, the wheels barely fit. This means I had no way to hang the wheels for painting and or curing in the oven. As a result, I broke the powder coating process into 2 steps.
1. Coat the back side of each wheel first and bake it to cure the coating.
2. Coat the front side as well as the inside of the rim and bake again to cure.

Note that the ground clip is not attached to the wheel. Due to all the little nooks and crannies in a Campy wheel, I found the Farraday Cage effect of charging the wheel and paint resulted in little or no coverage in all those recesses. So, I had to blow all the powder off to start over. I pre-heated the wheel in the oven and moved it to my spray booth and sprayed the powder coat onto the hot wheel WITHOUT electrostaticly charging the paint/wheel which resulted in consistent coverage in all the little closed boxed-in areas of the wheel.

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garth66garth66"When speed is the only thing that counts"
This is how the wheel goes into the oven after the front side is coated. As you can see, the wheel barely fits in the oven. Note the angle-steel base assembly is a frame I welded together to support the wheel without allowing it to rest on the oven rack so as not to mar the finish of the powder coating. There are 3 lag bolts welded to the inside of the frame, and the back of the wheel's hub rests on the pointed tips of the 3 bolts. The 3 pinpoint dots left in the finish are barely noticeable, but will not be seen anyway.

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C comp2Member
I powder coat a lot of small - medium size parts. I got a podercoating "phone booth" for $50 at a local auction. I wired the push button into a switch so I do not have to sit and hold it.

The kiln I made a circuit to control the kiln. I push a button and it operates, or I can specifically program the peak and hold temps and times.

If you look at that 55 gal drum on wheels ($10 from rural king) I powdercoated over the barrel for a long time. Most of the powder would fall in the barrel....most.

garth66garth66"When speed is the only thing that counts"
quote:
And BTW the wheels look great!

Thanks Gary!

Love that powder-coating phone booth; I have booth-envy! Actually, I have workshop-envy and skills-envy (constantly impressed by your fabrication skills!). My makeshift box booth does allow me to collect most of the powder that doesn't end up on the part so I can re-use it. I also found that buying powder from a local industrial paint supply (Cardinal Paints) is SUBSTANTIALLY cheaper than buying from Eastwood or even a number of other online sources.
C comp2Member
I do 100's of this and that which is not fancy...brackets and such for darn near everything. My most commonly used color is Matte black form Harbor Freight.

http://www.harborfreight.com/1...tte-black-93306.html


2 other colors I like a lot is Silver Vein and Gold Vein. The battery box is gold vein but should have been silver vein to match the roll bar and other parts:



There is also a black wrinkle finish which is nice. It is a little tricky. The amount coated has to be just right.
bosswrenchbosswrenchMember
As has been mentioned before, combining magnesium annealing with powder-coat pre-cure baking can be done, but don't skimp on the time at temperature. Lockheed Missles & Space Co uses 275F for 4 full hrs to anneal mag, followed by really slow cooling. Depending on how clean you got the porous casting and what (if any) solvents were used to clean, shorter bake times or higher subsequent cure temps can result in pinholes or bubbles in powder coats, as 'stuff' slowly bleeds out at the higher temp.

SLOW cooling to ambient is also important in annealing- wrapping the hot, baked wheel in an old blanket, putting it back and turning off the oven until morning works best. And some powder materials need more heat than 275F to fully cure. I've seen some that needed 500F or more! Some shops will no longer powder-coat cast magnesium due to expensive experiences in learning how to properly handle our porous wheels. Much of the trouble comes from skimping on the time-at-temperature by being in a hurry.
garth66garth66"When speed is the only thing that counts"
quote:
HEY Garth; Is THAT A 1970 Mach 1 wimbleton white mustang in the background?!

Yup! It's currently a shell on wheels - my next project as soon as I finish the 66 GT Fastback (my first car). I have a TON of NOS parts for the Mach 1, as well as a fresh 351C that was originally built for a Pantera (the original rebuilt engine, rebuilt top-loader, and a rollaway tool chest were all stolen when someone broke into the garage some years ago).
Last edited by garth66
larrywlarrywMember
Nice job.

Any issues getting the powder to bond to the JB weld? Evidently it can take the heat of the curing, but I thought powder would only bond to a chargeable (conductive?) surface.

Generally, any ideas on how to get old powder coating off a set of Campis for annealing and application of a fresh coat? I have some flaking and the mag beneath is turning black.

Does anything dissolve it? Will it de-bond under slightly greater heat than what it takes to cure it? How much heat can the wheels take? If it must be blasted off, what media would be recommended? It's pretty tough stuff.
garth66garth66"When speed is the only thing that counts"
quote:
Any issues getting the powder to bond to the JB weld? Evidently it can take the heat of the curing, but I thought powder would only bond to a chargeable (conductive?) surface.

No issues at all. I found that I got better results by NOT charging the wheel/paint due to all the tight pockets and crevices in the wheel design, so conductivity was a non-issue. JB Weld supposedly has metal in it, but I have no idea if it's conductive.

I preheated the wheels (10 minutes at 400 degrees) then sprayed them with the powder coat. As soon as the powder hit the hot wheels (JB Weld included) it would begin to fuse to the wheel. Once I had a sufficient coat of powder, they went back into the oven to cure (10 minutes at 400 degrees - the paint manufacturer's specification).

quote:
any ideas on how to get old powder coating off a set of Campis for annealing and application of a fresh coat?

I wondered about that when I was coating my wheels. Not sure what the best method would be. Probably use a heavy coat of aircraft stripper to break down the finish. I expect it would take several applications. Here are a couple of resources I found online for how to strip powedercoat...
http://www.powdercoatguide.com...at.html#.VRCMWOEYFrI
http://www.trx250r.net/forum/t...ain-ass-anymore.html
https://www.youtube.com/watch?v=YbMfGgX8wps
larrywlarrywMember
Wouldn't the acetone/powder solution tend to creep into the pores of the magnesium and worsen the outgassing problem?

Stripper seems to lift an old finish as a layer.

Maybe get the bulk of it off with the stripper and clean up with the solvent. It will still probably require a light bead later to get the last of it.

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