In this segment from Friday's Investor Beat, Motley Fool analyst Ron Gross tells investors why he'll be keeping a close eye on 3-D printing company ExOne (XONE) in the week ahead. Now that the stock is off 48% from its high, Ron says that he's becoming interested at these valuations. As the company operates in the far more lucrative industrial manufacturing side of 3-D printing rather than the consumer-focused hobbyist side, Ron likes the space the company operates in, and will be watching closely when it reports earnings next Wednesday.