NEW YORK— Talk to Tom Otterness about how he produces his sculptures, and the atmosphere he evokes is more that of a factory than an artist’s studio. In fact, he readily admits that making his pieces is “very similar to a 19th-century manufacturing project.”

Otterness’s sculptures are instantly recognizable: Cast in bronze, they might be a few inches or several feet tall, but they mostly represent a cartoon-like race of characters, often smiley-faced and bulbous and almost always charged by a scarcely veiled political subject matter. Economic and social inequities, rampant commercialism, the lot of the dispossessed—these are the recurrent themes of his sculptures. Otterness estimates that as many as 90 percent are made in response to public commissions, which, because of the complex decision-making procedures of the commissioners, often means a long, drawn-out process. An Otterness sculpture can often take more than five years from conception to completion.

The artist’s studio is a 17,000-square-foot converted factory (which used to produce vacuum-cleaner bags) near Brooklyn’s Gowanus Canal, and it houses a regular team of between 15 and 20, of whom 4 or 5 are office staff kept busy preparing and submitting proposals and overseeing contract negotiations and production and payment schedules. Otterness jokes that their most important job is keeping him within budget: “I’ll come up with an idea and they’ll wrestle me to the ground!” he says.

The rest of the staff comprises the manufacturing team, which assists Otterness at every stage of a sculpture’s development, though his approach is essentially hands-on. Every piece begins with a small-scale model in water-based clay or, less frequently, wax that Otterness makes himself. These provide the basis for a scale model and then a full-size version, both of which are produced on computers staffed by CAD and animation specialists—“I don’t even know how to turn the computer on,” Otterness admits—that communicate digitally with computerized routers to cut a rough version of the sculpture from polystyrene foam. At both the scale-model stage and the full-size stage, Otterness refinishes the cut foam form with a layer of clay applied by hand, and as a consequence the piece often undergoes “pretty major alterations” along the way. The full-scale model is then cast in plaster to produce a rubber mold that is shipped to an industrial foundry, the first point at which the process leaves the studio.

Otterness uses four or five foundries on a regular basis. One is in upstate New York, one is in Pennsylvania, and the others are in Arizona and Washington State. He has a feel for which will be best suited for a particular job but, in keeping with his entire process, he asks them all to make competitive bids for the work. Once cast in bronze at the foundry, the sculpture is smoothed and patinated by hand, first by members of Otterness’s team and then by the artist himself. Once completed, all that remains is transporting the sculpture and installing it in its eventual location. “There’s a lot of going back and forth,” he admits, “but I’m from the old-fashioned school.”