Proto Lab's stock rose nearly 14 percent Thursday as the prototyping and custom manufacturer reported strong growth in fourth-quarter sales and profits.

The fast-growing Maple Plain-based injection molder, milling and 3-D printing firm saw sales jump nearly 32 percent to a record $73.8 million during the quarter. The newly acquired and German-based 3-D printing firm, Alphaform, contributed $5.1 million.

Profits grew 17.7 percent during the quarter to $12 million, or 45 cents a share.

Excluding acquisition costs and other nonrecurring items, earnings were 50 cents a share, 3 cents better than analysts expected. Revenue beat analyst's expectations by more than $2 million. For the year, revenue rose 26 percent to $264.1 million, while profits grew 11.7 percent to $46.5 million or $1.77 a share. Excluding nonrecurring items, earnings were $1.97 a share. Analysts expected $262 million in annual sales and $1.94 per share in annual profits.

Delighted investors shoved Proto Labs' stock up 13.55 percent, or $7.16, to close at $60.02 per share Thursday.

CEO Vicki Holt told investors during a conference call that the quarter "was a strong ending to a very good year."

Proto Labs makes customers' product prototypes, acts as a contract manufacturer and works with hundreds of firms to ramp up and commercialize early-stage products.

In recent years, Proto Labs greatly expanded beyond its roots in plastic and metal injection molding. Today, "CNC" milling/machining services generate 28 percent of company revenue, while the recently acquired 3-D printing businesses now represent about 9.4 percent of annual sales. 3-D printing alone grew to $25 million in sales last year from just $9 million in 2014.

Holt said Alphaform will be integrated into Proto Labs in 2016 and begin adding to profits in 2017.

Dee DePass • 612-673-7725