I was recently in Helsinki, where wrought-iron gates like the one above are still a common sight (at least in the Punavuori neighborhood I crashed in). I remember seeing videos of iron being wrought in our second-year Production Methods course at design school, but it was mostly footage of singular artisans working the material with hand tools; in Intro to Welding, before we were allowed to touch the torches, we learned how to hammer out primitive shapes and curlicues by hand.
Some of the machines we saw in the videos resembled mere pipe-bending jigs, like the one used to produce the gate below:
Not terribly sexy. But there are, of course, far more sophisticated machines used to produce wrought iron shapes. A multinational manufacturer called Hebo—which credits themselves with "[having] invented the modern wrought iron machine and [being] the worldwide leader in this field"—makes a variety of machines designed by German blacksmiths. One of the things they can produce are the wrought iron "onions" or baskets you sometimes see used as finials:
I'd always wondered how those things were made. Check it out:
That's not all they can produce; by mix-and-matching various Hebo machines with their assortment of jigs, fixtures and add-ons, one can create all manner of wrought iron shapes:
You can view their full machine line-up here.