I'm going to post somewhat of a 'how-to' but it's more of a 'what I did' to clean up the legs on one of my SJs. Please don't think that you have to agree with this, or that this is necessarily the right way to do this. It's kind of an experiment on my part. The real test is to see what this looks like 5 or 10 years in the future...
Anyway, I have a Copper SJ that was in rough shape for such a collectable grill. The main shell of it wasn't dented or chipped, just REALLY dirty, and the legs had some rust on them. I didn't take much for 'before' photos, but here is what I was starting with. You can't see it in these pictures, but the inside was CAKED with the remains of many grillings. It was kind of a diamond in the rough just waiting for some lovin'.
As you can see, the legs are not horrible, but they certainly didn't add to the beauty of this fine SJ, so I decided to do something about it.
The first step was to remove the rust as well as the remaining plating on the legs. I've noticed that these the plating on these legs is very thin and weak, so I figured it was best to just start over.
The first step is to clean the legs of any grease, then put them in a PLASTIC container and add muriatic acid to remove the rust and plating. You can find muriatic acid at any home-improvement store in the pool dept.
I need to stop now and warn you. Muriatic acid is VERY caustic. You MUST do this outside, and once you add the acid to the container, you need to step away as the fumes are horrible and very dangerous. I learned long ago that you also do not want to use this acid near any tools. The fumes that rise up will form a fog and rust anything made of metal in the general vicinity. Eye protection and thick gloves are a must! If you're outside (you should be outside with this) you also need to pay attention to the wind direction. Do not be 'downwind' of this as you add the acid. Stay upwind and step swiftly aside after adding acid.
Here are the legs and lid-holder arm bubbling away...
Notice how when the acid is done working, you are left with a YELLOW liquid (that used to be clear) and the legs have a grey hue to them. No rust!
These legs are now raw steel free of rust and plating. I used a rubber-gloved hand to remove the legs from the acid, and dropped them into a 5-gallon bucket that was filled with water. The water will neutralize the acid, you can reach in with your bare hand after this, give them a quick rinse under a hose, and set them in the sun to dry.
I don't have any pictures of this, but as they are drying, the legs will form a light rust on them. I polished most of this rust away with some fine steel wool, then wiped them down with lacquer thinner, and sprayed them with a Rustoleum 'clear' engine paint, which is good to 500-degrees.
That's it, you're done. After the clear coat has dried, it's time to reassemble your grill. My hope is that this clear-coat finish will prevent any future rust from forming. Only time will tell. Do NOT go doing this to every SJ you own thinking that this will keep these legs from rusting. I tried this as an experiment, and so far I am happy with the results, but we do not know how long this will last.
Here are some 'poser' shots of the grill since I did the 'oven cleaner thing' and got the inside all shiney too... (By the way, a wire brush and some WD-40 will go a long way toward making some very used grates look better.)