New answers tagged preparation
None of the above? It's structural steel, you can just leave it rusty (if it happens to be corten, the rust actually keeps it from rusting further...) This may lack Wife Approval Factor for your backyard BBQ, however. Least marking (and least direct effort, dust, noise) electrolytic rust removal - submerge it in a tub of water, outside, with sodium ...
TSP and a sponge mop. Wash the walls once with a TSP solution, then again with clean water to remove any soapy residue. This stuff really works, so that means if you've sensitive skin, wear those big rubber cleaning gloves.
Using a Dyson, vacuum the wall.
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