Most of the iron wire of to-day is made of low-carbon steel, which corrodes very quickly. The cheapest protection is galvanizing, though tinned or coppered wires are more effectively protected.

Galvanizing and tinning are done by passing wire from one reel to another first through a bath of weak hydrochloric acid to clean it, then through a wiper of waste. It is then pulled under suitable guides through a bath of molten zinc or tin, according to whether the process is galvanizing or tinning, and from this bath it passes through a wiper of asbestos fiber to remove lumps of the coating material before it cools and is wound into a coil.

Pickled wire coils dipped into copper-sulphate solution take a coating of copper, and when drawn the wire has a bright copper surface.