LawRens

I will soon be tossing on a set of 18" monoblock IIs on the c43, and I'm looking for your opinions on either powdercoating or painting them. They're currently chrome plated, and I prefer an oem silver or gunmetal face.

As I've researched, there are people who mentioned that powdercoating can decrease the structural integrity of the wheel, as it's being heated to temperatures they were not meant to be in. There are those who rebut that as long as they're heated properly, there won't be any problems.

Do you think the risk of powdercoating is simply overstated, or is it a better idea to just have them painted?

nd4spd13

Realistically, I doubt you will face any times where having them powder coated proves to be an issue. I have never heard of anyone with powdercoated wheels having a problem.

ECTurboGSX

Powder coating requires curing at 400 degrees F, well below a temperature that would have any sort of impact on the structural integrity of a metal wheels. Many wheel manufacturers use powder coating on their own wheels.

DRBC43AMG

If I have to choose, it would be powdercoating any time

jmrscuderia

powdercoating they will last longer and look much better

503C43 ////AMG

I work at a steel foundry and have some insight relative to heat treatment of metal.

According to AMS-H-6088(SAE specification for the Heat Treatment of Aluminum Alloys) most alloys will not anneal until apprx. 650°F. Powder coatings typically cure at or below 400°F and cure for less than 1 hour.

That being said, in order to provide a sound metallurgical opinion on this, one would need to know the casting alloy and heat treat condition (i.e. T6 or whatever). Many common casting alloys, such as 356, are aged at 325F . If exposed to a powder coat cure schedule of 375-400F for 10 minutes or so, some overageing could occur and the fatigue life of the wheel could be reduced. It all depends.

I would suggest finding out what alloy the wheel is made of and go from there. There is no way anyone here could tell indefinitely if it is ok to powder coat your wheel without knowing the alloy, specific temperatures, and time exposed to those temperatures.

Hope this helps

LawRens

It's great that you mentioned that, because the general concensus from dozens of other forums is that exposing to 400 degrees Fahrenheit for too long is enough to weaken the alloy in 6061 T6, which seems to be the standard alloy for wheels. I've been trying to find what Mercedes OEM makes their wheels from, but no luck yet.

That's definitely what i'm hoping for. I don't plan on tracking, so I feel that it should not be a problem.

Thanks for all the input. Overall I have a feeling that the risks are overstated on forums, but it never hurts to be too careful. It appears that the more important thing is to find a good shop that knows how to powdercoat correctly.

ECTurboGSX

I was surprised to see that the T6 heat treating was done below 400 F. Here is an interesting discussion on powder coating wheels:

http://www.eng-tips.com/viewthread.cfm?qid=151053


Here is a whole study done on the issue:

http://digitalcommons.lmu.edu/cgi/vi...ntext=mech_fac