Proto Labs shares rose 6 percent Thursday after the fast-growing company's second-quarter profit beat investor expectations.

The company earned $11.9 million, or 45 cents a share, adjusted for one-time expenses. That was 3 cents better than analysts had forecast and came on a 33 percent jump in sales to $52.9 million.

Maple Plain-based Proto Labs is a quick-turnaround maker of custom parts, prototypes and molds for other manufacturers.

The company also said that Chief Financial Officer Jack Judd will leave by the end of the year. Judd, 57, has been with Proto Labs since 2011 and guided its initial public offering in 2012.

"Our company is in excellent shape and I leave knowing processes are in place to continue our growth strategies," Judd said in a statement.

Evan Ramstad