We introduce a technique for 3D printing soft strands, fibers, and bristles using conventional 3D printers. Our work was inspired by the phenomenon that occurs during the operation of a handheld glue gun: when a person extrudes hot glue material and moves the gun away, a “string” of residue often forms unintentionally. The shape, length, and thickness of the resulting stringy material varies based on how much glue was extruded and how fast the user moves away from the extrusion point. This artifact often annoys users, but in this work, we exploit the phenomenon.

The operating principles of a glue gun are similar to FDM-based printing techniques. By emulating the stringing behavior using FDM printers (which happen to be the most affordable class of 3D printers in the market today), users can easily add strands of hair, fiber and bristle to their 3D printed models as easily as a material property selection. Our technique is straightforward and easy to integrate with existing 3D printing workflows. Users can specify regions of their model where they want to incorporate hair, and our approach automatically generates the machine instructions (i.e., G-code). Moreover, users can easily specify parameters, including length, thickness and hair density. By using different filaments, hair color can be controlled as well.

Research Team: Gierad Laput, Xiang 'Anthony' Chen , Chris Harrison