I was drilling holes in 3/16" steel yesterday at my DP in support of a retaining wall project I'm working to complete and the level of smoking hot metal chips, even with continual "cooling" with WD-40 was amazing. That's about the extent of the metal working I do, but it would give me pause to surely separate metal working from woodworking. I'd not be so concerned about the walls, honestly. Rather, ti's keeping the "hot mess" separated from the wood dust and chips ("kindling") in my mind.