Originally Posted by redeu3
Have you done it? post some pics here. :-)
I plasti-dipped the stock 400M's on my 328i M Sport and have been completely satisfied with the results. The finished product looks exactly like what you'd expect from having the rims powder coated matte black, but for a fraction of the cost as well as the ability to reverse later.
Go check out the tutorials on the dipyourcar website and you'll have pretty much all the info you need to DIY. Some personal tips I can offer are: like others have said, be sure to pass on the lazy methods of spraying the wheels while still mounted and just take the wheels off the car to plasti-dip them. Its the only way you can get the full coverage needed to ensure an even finish across the rim.
I recommend applying a total of 1 can per rim, which will ensure the plasti-dip coating is thick enough to resist normal wear and tear. A thick coating also makes it easier to peel the plasti-dip off if/when you want to do that. Clean the wheels meticulously and once they dry, I recommend wiping the rim surfaces down with rubbing alcohol as it helps the plasti-dip bond to the glossy finish of our stock rims. From there its just a matter of simple spray-painting techniques to apply the plasti-dip. First coat should be ultra-light, and the following coats should be light enough to ensure no running or bubbling. Depending on the conditions I've found a good 20-30 mins of drying time is needed between coats, and once finished you should allow as much as 12 hours for the plasti-dip to cure before re-mounting the rims. Be careful with your breaker bar and torque wrench when putting the wheels back on; you don't want to rub against the rim and tear the plasti-dip surface.
Hope that helps and be sure to post some pics of the finished result!