A three-dimensional (3D) printer is one of the mechanical tools controlled by computers and is commonly used in "digital fabrication." The 3D printers have recently attracted much attention because of the State of the Union Address by US President Obama, the Maker Movement, and the market entry of affordable 3D printers. In contrast to the boom, however, accurate information on the actual capability of 3D printers is lacking and remains ill-defined. In this paper, the capabilities and application potential of 3D printers are presented from the perspective of a service bureau. The main discussions are focused on the following: (1) 3D printer is a digital mechanical tool that manufactures prototypes whose shapes are complex and are not suitable for removal processing, (2) it is not suitable for mass production from the viewpoints of cost, mechanical strength, and safety, and (3) it can manufacture only one high-value-added product by combining other techniques such as painting, casting, and so on.
