Honestly, I had no idea what condition the alloys were under the various spray paints and factory paint that were on the rims. They looked so sad it wasn't really possible to judge the condition of the wheel. Thus for a proper restoration, there were no alternatives but to sodablast them to bare aluminium and then repaint.
Had them sodablasted at a local business who have just started this summer: Karjalan Soodapuhallus. The cost was very reasonable and kept some sense in the restoration idea. The company was great to work with; accomodating, quick, professional. Warm recommendations.
Sodablasting is, in my opinion, the proper way to strip paint from aluminium wheels. Sandblasting is too rough on the surface, it leaves an uneven surface that looks a lot like sandpaper itself. Sodablasting, on the other hand, strips no medium and thus leaves a smooth surface ready for finishing. Glass blasting, while better than sandblasting, is messy and expensive. The problem with sodablasting is finding someone willing to do the job; it is a new profession and requires expensive hardware, lots of work to execute and soda isn't cheap either. Mercedes-Benz and AMG wheels have incredibly tough factory paint on them which makes sodablasting them a particularly expensive thing to do. I was told the sodablaster had his hardware set on a setting an order of magnitude higher than he would normally do, and soda consumption was silly. He should've charged more, but we had agreed on a price, and he honored it.
Fortunately, the alloys look almost pristine now that they are bare aluminium. No curb rash, no dents, not even stone chips or even scratches.
New finish is not set in stone yet. I'm hoping for 199 (body color) with polished lips but there are some problems with that.
- Powdercoating is the proper way to do aluminium wheel restoration. Spray painting is unreliable for wheels that get used daily. One stone chip and you might be getting clearcoat peel or oxidation. Painting aluminium takes special expertise and cannot be done well by someone who is only used to painting cars, for example. But, there is no powdercoating place nearby, and powdercoating the 199 color is difficult and expensive.
- Having a paint shop spraypaint the wheels with a proper color costs 400 EUR locally, and they can't guarantee a perfect result in spraypainting a wheel with its complex shape, they would rather have me powdercoat them.
- Polishing the lip would require some sort of apparatus for spinning the wheel, I don't have a clue how to go about that and it'll no doubt be pretty expensive without a junkyard nearby.
- The one paint shop I've asked will not do a two-tone paint job (199 with chrome paint lip).
I gained some contacts at Itätähti which will hopefully resolve some of those issues. I always have the backup option of going to single color (astral silver), which would still leave me with all the problems of spraypainting.
Single color black or bodycolor would look extremely tacky on this car since the body has so much brightwork.
I will have to make the decision soon, because aluminium oxidizes in air. I only have a couple of weeks before the wait will have hurt the new finish.
Stay tuned for how the wheels turn out.
