It’s Just Cool:Spray Arc Metallizing
The other night while half-watching a Modern Marvels episode about the Pacific Coast Highway, I happened to look up and see a worker spraying molten zinc onto the underside of a concrete bridge. Two of my favorite things, liquid metal and high voltage, combined in a way I’d never considered before! It’s moments like this that let you know you’re a tool geek.
Spray arc metallizing is a way of adding a thin coat of metal — typically zinc or aluminum — to a substrate material by heating it to a plasma state and propelling it out with an inert gas. The molten metal quickly solidifies and bonds to the substrate creating a corrosion resistant layer.

When used on metal it won’t flake off like paint, and it prevents “chloride induced corrosion” when used on concrete. It’s an important part of shoring up crumbling infrastructure as well as looking pretty freaking awesome.
Arcspray 170 [metallisation.com]
It’s really a good thing I’ve never gotten my hands on one of these rigs as I’d be spraying everything I could think of. I suppose when you’ve got a hammer everything looks like a nail.
You can’t fool me! That second picture is a still from “Amazon Women on the Moon’ the 1957 sci-fi cheese fest starring Tab Hunter and Ava Gabor!