How Clear is "Clear" Powder Coat

[Jeff Higgins]

I just had a set of wheels sandblasted and clear satin powder coated, hoping for a dull/frosted aluminum finish. The clear powder coat has a definite beige or tan tint to it. It looks a lot like the default border color for a lot of Windows applications. In other words, not even close to a natural aluminum color. Is this a process limitation in powder coating, or should it be possible to provide a truly clear finish? These really look like crap, by the way.

[Scooter]

I saw these wheels this weekend, and they definitely do not have an aluminium color finish. They really do look beige. I would like to see a pic of a wheel that had the powder coat done correctly. I am sure it would be helpful for Jeff to see the diference.

[88-diamondblue]

It should be clear. I did these in high gloss clear after bead blasting them.

[75blkcarrera]

The clear powder coating is baked at a lower temperature to keep it from yellowing or turning colors. Could the powder coater have over baked them? Some powder coaters do a trial run on a new batch of powder to be sure that the color or in this case the lack of color is what the person is looking for. I understand that getting the powder coating off can be hard. good luck.

[slammed1000]

i have always noticed that the clear seems to add a milky color to polished or lighter colored parts. my buddy has a shop and has samples of what it looks like to show his customers as he has had a few bad experiences with it.

[Jeff Higgins]

The powder coating shop now tells me the discoloration is a result of the sandblasting. Something about the porous surface being heated to 400 degrees to cook the powder. They say it will not happen on a smoother surface, like bead blasted or sanded. The guy said he can chemically strip them and re-coat them, but it would be fruitless as the base metal is discolored.

The good news is that they agreed to re-coat them in the color of my choice. He tells me they can re-heat them and "hot spray" over the existing clear, and it will bond to that just as it would to a freshly sand-blasted surface. So now I'm looking at various satin and flat blacks; he has a range from dead flat to gloss. I'll be dropping off the wheels and checking samples this afternoon.

[Steve 82SC]

After I had my Fuchs polished by Al Reed, he put a clear powdercoat over the bare aluminum to negate the need for polishing. There's absolutuely no yellowing or tint to be seen on his job.....very clear.

Steve

[ventana]

I suspect that your powder coater overheated the application. That is what causes the discoloration, not the texture of the substrate. I used an air cure, clear epoxy on my Fuchs and had only a slight dulling of the original polished finish. It's been over a year and still no discoloration. I don't use any abrasive on it though.

[Jeff Higgins]

I went in and spoke with the powder coater last night at some length. He showed me lots of examples of clear over different underlying surface finishes (why didn't he do that in the first place?). Anyway, it looks like the final color very much depends upon the underlying surface prep. Polished, lightly sanded, soft media blasted, etc. all result in a true natural aluminum color after powder coating. Rough sand blasting does not.

He is completely re-doing them at his cost anyway, so it's no skin off of his nose to re-do them in clear over the sand blasted surface. He did emphasise they would turn out exactly the same way as they did the first time, so what's the point? He tell me that while you can "burn" clear powder coat, that is not what happened here. It's entirely due to the underlying finish. He appologized for not being "clear" on that point to begin with.

So, we looked at lots of options from aluminum colored, to a "chrome", to various sheens of gloss, satin, and flat black. I'm going with a satin black. Looking at the "early car inspiration" thread, I saw lots of all black Fuchs that I thought looked pretty darn good on those cars, so that's what I'm going with.