Powder coat rims?

[TJMart]

I am in the process of replacing my tires and am considering powder coating all 5 rims in a satin black. Is satin black the correct "black"? Are there any potential problems to be aware of? Thanks!

[wwheeler]

I powder coated mine years ago and they are great. I used a 60% black gloss which should be just about right. Satin is maybe about 40% and a bit dull. Might make sure they cover the seats for the lug bolts so that they don't get coated. The only other issue I ran across is the seam where the inner hub is welded to the outer rim. That crack seldom gets coated completely because powder coating doesn't flow like paint. I would take a very thin artists brush and paint that crack with semi-gloss black. That will prevent surface rust in the future.

Also make sure the company that mounts the tires uses adapters meant for powder coated rims. Most do automatically now because they are so common. Other than that, they will last a lifetime.

[TJMart]

Thanks Wallace!! I appreciate your expertise. I wasn't sure if the satin would look good on a rim so the added gloss should do it!

[wwheeler]

Here is how it turned out. This is a W111, but shouldn't make any difference. I also did the rims on the W128 as well. If I had to err on either side, I would prefer more gloss than less. If nothing else but for cleaning.

[Garry]

Just be a bit careful when first fitting them.  The coating should not be on the contact surfaces of the lugs or back plate.  It tends to be a bit thick and will break down when they are tightened and can then loosen wheel nuts on the first drive.  I found out when i powder coated some rims for a VW. Thankfully i realised what was happening before the wheel fell off.


A friend who engineered for GM explained the finer subtleties of painted wheels and paint thicknesses

[TJMart]

They look great!

On a side note I think I read on this site that there are coated hub cap anchors (can’t think of the specific term) that prevent the rims from getting scratched when you install them. Do you recall anything like that?

[FresnoBob]

I powder coated mine satin black at Les Schwabs for a very reasonable price (which i don't remember). 

[wwheeler]

They do have a plastic covered clip that was available for later cars with aluminum wheels and hubcaps. Part number is #123 400 00 27. I have those on now and they do a great job of not scratching. The hubcaps are much easier to pop off as well. I worried about the clips not gripping the rim enough, but have yet to have a cap fly off in 10 years. It shows to be possibly available and around $30/wheel.

Garry has a good point about powder coating. This applies to ALL powder coated surfaces that are being tightened down with fasteners. When you tighten a bolt or nut on a powder coated surface, it will crack/peel the coating on and around that surface. If it is a critical torqued fastener like a wheel lug bolt, that will be a problem. The area must be taped off in advance of coating or removed later. Same goes if it is a sealing surface like when copper sealing rings are used. Once the fastener with the seal ring is tightened down on the coating, it will crack the powder coat and cause a leak. Guaranteed. So powder coating does have limits of applications. 

[Benz Dr.]

I had a car come in once and they had powder coated all of the sub fame parts - and I mean ALL of them.. It took me hours to remove everything from threaded or close tolerance surfaces. That was it for me and powder coating.

[mdsalemi]

Over the years, with all the various items I've had restored on my car, I've always chosen powder coating when possible. Sadly, my powder coater gave up the business a few years ago.

I've never had any issue with powder coating. Just like any kind of coating--be it paint, or plating, you have to be careful. You have to plug threaded holes, for example. On surfaces meant for electrical contact, you need to leave a contact spot. Those are just two cautionary items, and the same holds true for plated or painted surfaces. A good powder coater would and should know all of this stuff.

I've had all my wheels powder coated, and I have the 6" aluminum ones. I've had many sheet metal parts powder coated, such as the radiator cowling, some bracketry, and the air cleaner housing and assembly. I did the battery tray and hold down. I've had the aluminum fan blade powder coated too. I've never had any issue with any of my powder coated parts. They hold up exceedingly well and due to my [former] powder coaters meticulous if not perfect preparation. When I brought my wheels in the first time, the original finish was powder coating (according to their tests) so they used a special process to remove the old before replacing with new. They specifically did not sandblast the finish so that the Lemmerz logo as well as the part numbers would not be obliterated.

The one failure I had was the coolant overflow tank. We suspected that the pre-bake process would melt the solder holding it together, and sure enough--it did. What we did not expect was to find what amounted to a swiss-cheese like perforation in the tank once the solder repairs flowed out. So, living in "ground zero" for the automotive world, it wasn't too hard to find an old-school radiator shop. They repaired the overflow tank and pressure tested it. I then took the tank to my trusted repair facility, Motorwerks, and they painted it the correct satin black...which identically matches the powder coated pieces in the engine bay.

I replaced my auto transmission filler tube some years back, and the original (cracked and cadmium plated) had been replaced by Mercedes with one powder coated. My plater removed the powder coating and properly plated it with the yellow chromate cadmium. I don't know what he used to remove the powder coating but it wasn't too bad.

So, don't be frightened of powder coating. My restorer did all my subframe components and he didn't have any issues either. Just be smart about what your doing.

[wwheeler]

Like Micheal, I have powder coated many things on my car. It is my preferred method if it is suitable. I have even powder coated the aluminum oil and fuel filter housings and used the same color as the valve cover. That was my point about surfaces that are sealing. In the area where the fluid fittings with seal rings are attached, you cannot have powder coating. It will leak 100% of the time. So you just tape that area off with high temp tape in advance.

Most items under the hood or underneath do not have critical torque fasteners. But the ones that do, you have to be careful where the powder coating goes.

[RAY]

Thanks for the tip on the plastic covered hubcap clips Wallace.
I have recently powder coated my set of aluminium steelies and as soon as i put the caps on they began to mark them.
One question -
Are the clips you refer to metal that has been plastic coated or solid plastic ?
Best
Ray

[wwheeler]

They are metal with plastic caps on them. They seem very durable.