Why not just do it yourself? It is not difficult, just takes some patience. If you are not willing to do it yourself, I will do it for a couple of bucks.
I helped a buddy do a set last year and the duplicolor ended up looking like rhino-liner. I don't want to F up my wheels like that. Got any suggestions on the most important steps?
I heard that powder coating can potentially compromise the structural integrity of the wheels and should not be done to wheels that see track/heavy duty.
Who told you that BS? If an alloy wheel can't take 450 degrees for 30 minutes I sure as hell wouldn't mount them on my car let alone put them through the paces on a track. If you want comfort in a wheel design that will take track abuse look for wheels that are TUV approved. That is the German equivalent to our DOT but have speed and crash standards for wheel designs. OZ, BBS, Rays all meet or exceed those standards along with others I'm sure.
I have heard the same thing as Bolderer. You run the risk of overaging the metal, which could lower some of its mechanical properties. Do a Google search for Powder Coating Structural Integrity and you will get thousands of results debating this. From what I have read, you should be safe as long as you do some checking before hand. What you need to check for: #2 seems to be the most important based on what you are trying to do. 1. you need to know the previous mechanical history of the wheel to know where you are starting from. What is the specific material? Has it already been heat treated? Has it been powder coated in the past? How long and what temp was it cured at? 2. then you need to know what parameters your powder coater will be using for the curing process (temp, duration, etc). 3. then you need to know your mechanics of materials. If a metal is material X with heat treat grade Y, and I then subject it to another XX minutes at YY degrees, what will happen to the material properties? What types of impact loads could the wheel handle stock...what types of conditions is the wheel prone to failing? Fatigue, impact, both? 4. TEST TEST TEST. Real world test data is key. In our case it is going to be hard to get this info because we don't want to go and try to bend one of our nice wheels for the sake of this arguement. Of course it helps to simulate on a computer (which most structural engineers with access to FEA software should be able to help you do, it will take some time to setup the models but if they know what they are doing you can get very accurate results). 5. make a conclusion on if it's safe. 6. ? 7. Profit (sorry, had to throw those in there) As for places that Powder Coat. Miller Powder Coating did Milos wheels a while back. I believe he paid about $50 a wheel and he was very happy. He had his stock BBS STi Wheels Powder Coated Black. They looked perfect. No paint chips or blemishes that I remember. Miller Powder Coating 4251-B Wayside Ct Lilburn, GA 30047 770-931-1505
Exactly. Plus I really want flat black, which I don't think you can get with powdercoating. Even as they are now, which I assume is duplicolor black (they were painted when I got them) they are too shiny for my tastes. I just want someone who can give me a good paint job, in flat black, for a good price. They are probably going to get beaten on pretty hard but I still don't want them to turn out looking like shit, especially right after i paint them.
I did the wheels on my GTi back in the day with flat black engine enamel. They looked pretty good after doing them.
I might just try something like that. I guess if I give em a light sanding and make sure they're super clean then the paint should probably come out fine, no? And that would definitely be the cheapest route. Plus, I guess I should add... What's "pretty good"? I have seen some pretty bad looking flat black wheels. What would be ideal would almost be an uber-dark matte grey or something. So that it looks flat black but not like it was spray painted.
depends...we did mine on the car without doing any kind of prep work before hand other than washing/cleaning them. No bubbling or anything. Sanding probably wouldn't hurt it though
You should definitely try it yourself. It will cost you probably around $20 or so to get the stuff necessary, Sanding Paper, Paint, etc.. If it doesn't turn out to your liking, oh well, $20 down the tubes, and then find a professional to do it. If it does work out to your liking, you just saved yourself probably close to $180.
We painted three sets of rims pink... just takes time and elbow grease. I used to work with several Metallurgists and ALL of them (one was a PE and one had his Phd) told me not to powercoat forged aluminum wheels...
356 AL alloy T6 heat treat is done at 310 degrees for 5 hours 356 AL alloy T7 heat treat is done at 425 degrees for 7 to 9 hours 6061 AL alloy T6 heat treat falls between the top two Now you out gas AL at 200-225 degrees for about 20 to 30 minutes, cool to about 150 degrees then shoot your powder. After powder is applied you cure at at 300 degrees for 12 to 15 minutes. My heat treating numbers are from memory but should be close, so I don't see how powder coating could cause a problem with "structural integrity" if properly applied. So once again I call Bull Shit. Besides the my friends mothers cousins brother in law story, I would love to see proof of a wheel failure attributed to powder coating.
You can call BS all you want, but many people believe that powder coating can cause structural damage. Here, a quick google search turned up this from a Metal and Metallurgy forum. http://www.eng-tips.com/viewthread.cfm?qid=151053&page=10
The key to painting and not looking like rhino-liner is to hold the can a few inches away from the wheel and to use light even strokes. Let stand (get tacky) then do it again. If you do it an inch or so away and put it on thick, it will look like crap.
I don't think that the curing process is necessarily going to cause structural damage to an alloy wheel. The issue lies more in changing the temper of the metal, which has been hinted at in previous posts. A forged bit of aluminum has had special care put into the manufacturing to achieve the correct molecular grain sturcture for durability. The issue lies with adjusting this by essentially reheating the metal and air quenching during the curing process of powdercoating. This can potentially increase the temper of the wheels making them harder. Unfortunately, most people don't realize that "harder" is not necessarily better. The harder the temper the more brittle the metal becomes, which could potentially be manifest itself as wheel failure at high stress loads. Just a metalworker's .02
I guess I'm gonna just do it my self. I already cleaned them up pretty good and I think I'll gibe them a light sanding today. What do you guys recommend for a good looking flat black? I heard engine enamel but what kind? Any other ideas before I go buy all the stuff I need?
clean the ever loving out of them before you do any sanding, you can use a brown scotch brite pad to knock the shine off then clean and tack before shooting. First coat should be real light and even and let sit for about five minutes before the second heavier coat.
You can also look for a chemical solvent to remove any traces of dirt or oil from the metal. The popular name escapes me at the moment, but it should be available at any body shop supply store. Just ask the guy at the counter. Good luck with your endeavor, take some pics when your done:bigthumb: