Been there and done that, Marv. It wasn't one of the more pleasant challenges I took on for my restoration, but I got through it and the grill came out pretty sharp. Problem is, the grill has 111 holes in it to address and each one has four sides. So you have 444 crudded and/or oxidized surfaces to address, and that gets tedious in a hurry. There is no raw (non-anodized) aluminum there, so all of the surfaces are "hardened", and that makes the job a little easier to accomplish without damaging anything. In manufacturing, some component pieces of the grill were given a mat treatment and others were made somewhat shiny, but then the parts were all given the anodizing treatment.
The method I used to recondition my grill - which took a mere 8 hours or so in my recollection - was to wrap 4/0 steel wool on a popsicle stick and work each surface individually by hand using naval jelly as a combination lubricant and chemical oxidation remover. It was really boring to do, but the end result when I rinsed it off was a huge improvement in appearance. The only cosmetic issue I remain displeased with is where someone in the past must have tried to clean a small area with sandpaper. Whereas lubricated steel wool will not cut down through the anodized surface of the aluminum, sandpaper walks right down through it. Then you have a mess that is a very big deal to correct.
I have an extra grill I want to tackle some day - the reason being that stupid small sanded patch - and I would like to try to get a little more help from chemistry when I tackle it. The first product I would like to try is toilet bowl cleaner - Lysol brand I think. There are two types of bowl cleaner on the shelf and you have to check the label. One works by bleaching with hypochlorite, and the other type works with a touch of acid. I think the acid type - used with caution - might clean the grill up with far less manual labor. The other chemical preparation I would try is "truck wash acid". We take our company truck down to a truck wash outfit for an occasional acid bath - especially after the winter - and the results are spectacular. I might just take the whole grill down there and have the truck wash guys do their thing on it. It is a very inexpensive process. Something has to be easier and better than manually working it a square at a time. I wish I had a wrecked grill to experiment on so I don't mess up a good one while playing with chemicals.
The "concours" way would be to completely dismantle the whole grill to restore it. You would take all the pieces down to the anodizing shop and have them de-anodized, which would return the aluminum surfaces to their soft, raw state. Then each part can be addressed for appearance - maybe polished for some, and media blasted for the mat parts - and then returned to the shop to to be re-anodized. A few minutes of complete reassembly and you have a new looking grill.
Any way you look at it, it's a challenge. It would be interesting to know what some shop would quote to "restore" one of these grills, and just how good you could expect it to look when they are finished.
Keith Boonstra
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