Friday, September 25, 2009

Wrought Iron Revisited


                   Cast Iron Railing                               Wrought Iron Component

One of my correspondents, Paul Rodriguez, whose own intriguing website, The Ruricolist, is reachable here, commented on my earlier post about wrought iron wondering if I preferred wrought or cast. “I do find them distinct,” Paul wrote, “since in New Orleans (I'm sure you know) each has its own dominion, wrought iron in the French Quarter, cast iron in the Garden District. My own preference is for wrought iron.” Well, Paul assumed too much—namely that I knew something about the subject, which, reading his e-mail, I did not. But I’ve since then become minorly aware of the difference—and, having looked, agree with him. Wrought is the way to go.

As always, in these matters, lifting the carpet reveals much more than you’d expected. Wrought and cast iron are produced by different processes, the first by blooming mills, the last by re-melting pig iron from a blast furnace with scrap. Wrought iron is porous and contains some slag; blooms or masses of it must be hammered to fuse the metal and to remove most but not all of the slag. The wrought kind if very tough, hard, and easy to weld—whereas the cast stuff is more brittle because it contains carbon. A genuine wrought iron railing, therefore, is twice-wrought, you might say: in the metallurgical production and later by the fabricator who hammers the pieces into shape.

I show examples of each above, from the same source, accessible here and here. As you can see, the cast product can also be quite fancy, but a close examination of such objects will reveal the differences. The human element is much more present in the wrought variety, and something in us does pick that up.

2 comments:

  1. Question : is cast iron not also "cast" as in made in a cast or mold? I've been observing cast iron and have come to the conclusion that many of the railings at windows in Paris have been made in molds. Some are quite recurrent. I can imagine cast iron factories.

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  2. Cast iron items are indeed iron poured into molds. Wrought iron items are made from blank pieces that are hammered into desired shapes--although the hammering and shaping may be done by machine tools, not necessarily by individual craftsmen.

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