Custom manufacturing firm Protolabs has expanded yet again, this time buying a facility in Brooklyn Park to house its growing computerized CNC manufacturing operation.

Terms of the deal were not disclosed.

The Brooklyn Park building now has 152,000 square feet, the company said Friday. It will be expanded by an additional 50,000 square feet before the end of the year.

The company will eventually house 375 workers at the site, which will focus on keeping up with customers’ growing demand for customized milled products.

Demand has been driven by customers who want smaller products, especially items that connect with electronics and gadgets that can facilitate the internet of things trend, said CEO Vicki Holt.

At its new site, Protolabs will hire 150 new workers over three years but more immediately transfer 225 workers there from the company’s now crowded 4-year-old Plymouth plant.

Additional workers will be hired at Plymouth to help with Protolabs’ fast-growing injection molding business, Holt said. The Plymouth facility now has 558 workers.

“We are just rocking and rolling here,” Holt said. “We have a great business model. We delight our customers [with quick-turn customized products] and they continue to want more. It’s just a great place to be.”

The expansions are just the latest in a number of moves for the Maple Plain-based firm that makes industrial prototypes and low-volume orders for customers around the globe.

“We are excited about the growth we’ve experienced in machining,” said Protolabs Vice President Rob Bodor. “Opening an additional facility in Brooklyn Park, along with investing in more machining and injection molding equipment around the world, demonstrates our ability to evolve and increase the services we provide to our customers as we capture share in this dynamic market.”

Protolabs specializes in injection molding, precise computerized “CNC” machining, milling, automated 3-D printing and other high tech manufacturing.

It was privately held until 2012 when it went public in an effort to grow. Since that time, it has almost tripled revenue.

In 2012, Protolabs had $115 million in annual revenue, $35 million in profit and 600 workers. Today it has $344 million in annual revenue, $52 million in profits and 2,300 global workers.

In 2014, Protolabs began expanding its Minnesota footprint. From its perch in Maple Plain, it opened its $19 million factory in Plymouth to specialize in injection molding and lathe milling.

It transferred 175 workers from Maple Plain to Plymouth in 2015, and since added nearly 400 workers in Plymouth.

“We have been bursting at the seams,” Holt said.

That’s why Brooklyn Park had to be added. The addition will allow Plymouth to take on some of the work from the company’s injection molding plant in Rosemount, Holt said.

Protolabs’ growth has been greater than that of the Twin Cities. In recent years, Protolabs purchased and expanded operations in North Carolina, Japan, England and Germany and beefed up its customer offerings to include 3-D printing, rapid overmolding and injection molding techniques using silicone and rubber.

In December, it paid $120 million for a New Hampshire-based sheet metal firm specializing in quick-turn production and prototypes.

In August, it added a new Hewlett-Packard multi-jet printing technology that can produce parts up to 10 times faster than past powder-based processes. Last year, it expanded its facility in Japan.

In 2016, it bought the assets of a German metal molding and laser business and had its team in England codevelop an automated overmolding ordering system. That same year it spent $25 million building new facilities in Raleigh, N.C., the same place Protolabs had entered the 3-D printing business two years earlier when it bought FineLine Prototyping.

Company officials said they will continue pushing the envelope on product development and customer service.

Holt said the company’s computerized “CNC” milling business jumped 27 percent last year to more than $100 million.

Investments like the one in Brooklyn Park is just one of the ways the company is trying to keep up with demand, she said.

Last year, Protolabs bought 75 computerized mills and 25 injection molding presses in the United States. It added another 25 CNC machines and six injection molding presses for its plant in England. In all, the company now has more than 1,000 presses, mills, lathes, press brakes, laser cutters and 3-D printers to serve 37,000 customers.