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MNBoxster · 03-26-2007, 09:05 PM

Hi,

As Denverpete aluded to, there are simply too many variables for such a Blanket Statement or Warning.

There are literally hundreds of different alloys out there and numerous ones used by Wheel Manufacturers. Then there are at least 35 different Tempering methods. Several can withstand temperatures as high as 279°C (535° F)

I have Powdercoated several sets of Alloy Wheels and Tracked several repeatedly with no issues over 15 yrs. of use, including a set of BBS Wheels.

The Shop I use heats their oven to only 320°F as they say this is sufficient to get the powder to Flow and it results in a better overall finish than higher temps.

The email from the guy at BBS isn't very specific with it's "We'd always prefer... " He doesn't catagorically condemn it. Sounds more like Risk-Management speak than anything technical.

Alloys, Tempering Methods, Oven Temps and particularly the Wheel design itself are all factors, and all often very different from Wheel to Wheel and Shop to Shop.

The interesting thing is that if there were a high incidence rate of failure of Powdercoated Wheels, I suspect that the major Wheel Refinishers would do one of 3 things, possibly some in combination.

To avoid liability, they's refuse to Powdercoat Alloy Wheels altogether.

Or, they would put a lot of disclaimers and waivers on the process.

Or, the prices would skyrocket to cover the cost of increased Liability Insurance.

The last time I had any Wheels Powdercoated, about 2 yrs. ago, they were $85/wheel which included unmounting the Tires, Media blasting the wheels, coating them, remounting and balancing the Tires. And this is a nationally known Wheel Repair Specialist.

I'm not wholly endorsing the process, but my experience has all been good and I wouldn't hesitate to Powdercoat a Name Brand Alloy Wheel, though some of the cheap knock-offs would make me more hesitant.

If you're really concerned and want more information, check out:

Properties of Aluminum Alloys: Tensile, Creep, and Fatigue Data at High and Low Temperatures - 12-16-02 - Publishers: The Aluminum Association / ASM International

Happy Motoring!... Jim'99

03-26-2007, 09:05 PM	#7
MNBoxster Registered User Join Date: Sep 2005 Location: Minneapolis/St. Paul, Minnesota, USA Posts: 3,308	Hi, As Denverpete aluded to, there are simply too many variables for such a Blanket Statement or Warning. There are literally hundreds of different alloys out there and numerous ones used by Wheel Manufacturers. Then there are at least 35 different Tempering methods. Several can withstand temperatures as high as 279°C (535° F) I have Powdercoated several sets of Alloy Wheels and Tracked several repeatedly with no issues over 15 yrs. of use, including a set of BBS Wheels. The Shop I use heats their oven to only 320°F as they say this is sufficient to get the powder to Flow and it results in a better overall finish than higher temps. The email from the guy at BBS isn't very specific with it's "We'd always prefer... " He doesn't catagorically condemn it. Sounds more like Risk-Management speak than anything technical. Alloys, Tempering Methods, Oven Temps and particularly the Wheel design itself are all factors, and all often very different from Wheel to Wheel and Shop to Shop. The interesting thing is that if there were a high incidence rate of failure of Powdercoated Wheels, I suspect that the major Wheel Refinishers would do one of 3 things, possibly some in combination. To avoid liability, they's refuse to Powdercoat Alloy Wheels altogether. Or, they would put a lot of disclaimers and waivers on the process. Or, the prices would skyrocket to cover the cost of increased Liability Insurance. The last time I had any Wheels Powdercoated, about 2 yrs. ago, they were $85/wheel which included unmounting the Tires, Media blasting the wheels, coating them, remounting and balancing the Tires. And this is a nationally known Wheel Repair Specialist. I'm not wholly endorsing the process, but my experience has all been good and I wouldn't hesitate to Powdercoat a Name Brand Alloy Wheel, though some of the cheap knock-offs would make me more hesitant. If you're really concerned and want more information, check out: Properties of Aluminum Alloys: Tensile, Creep, and Fatigue Data at High and Low Temperatures - 12-16-02 - Publishers: The Aluminum Association / ASM International Happy Motoring!... Jim'99 Last edited by MNBoxster; 03-26-2007 at 09:17 PM.