March 19 (Reuters) - 3D printer maker ExOne Co reported a surprise quarterly loss as it sold fewer high-margin printers and the company forecast 2014 revenue below analysts' estimates.
The company's shares fell 10 percent to $39.50 in extended trading.
ExOne's gross margin fell to 30.9 percent in the fourth quarter ended Dec. 31 from 49 percent a year earlier.
The company's printer sales rose to 12 units from 8 units, but it sold just three high-margin S-Max printers compared with five a year earlier.
The company forecast revenue of about $55 million to $60 million for 2014.
Analysts on average were expecting $61.6 million, according to Thomson Reuters I/B/E/S.
ExOne reported a net loss of $3.2 million, or 22 cents per share, for the fourth quarter compared with a profit of $902,000, a year earlier.
The company, which went public in February 2013, said revenue fell 16 percent to $10.7 million.
Analysts on average had expected a profit of 1 cent per share on revenue of $12.1 million.
ExOne's revenue from printers and other machinery sales, which accounted for 66 percent of total revenue, fell 22 percent.
The company also sells printing parts and materials.
Shares of larger rivals 3D Systems and Stratasys also fell after ExOne's results.
3D Systems' shares were down 1 percent at $61.99 in trading after the bell, while Stratasys's stock was down 1.5 percent at $114.54. (Reporting by Sruthi Ramakrishnan and Soham Chatterjee in Bangalore; Editing by Kirti Pandey)