The Rotrics DexArm [1] supports 3D printing, laser engraving, and other functions with quick-change end-effectors. Their Kickstarter delivered the desktop robot arm last summer; now they also sell through Amazon. The 3D printing volume is "bigger than 220 x 220 x 270 mm (8.6 x 8.6 x 14.9 inch)." I have printed dimensionally sensitive models such as Raspberry Pi enclosures.