A Parametric 3D Knitting Workflow for Punchcard Knitting Machines

Punchcard knitting machines allow automatic needle selection based on a punched pattern. The machine reads the card and translates a punched hole to specific knitting actions. Punchcards are usually purchased ready to use or manually punched by the user. Current tools allow the digital fabrication of punchcards, however those tools focus on two-dimensional graphic patterns. This work introduces a parametric workflow for designing and fabricating custom-made punchcards that enable 3D knitting and shaping. We demonstrate our workflow using two case studies that implement short-row knitting to obtain 3D surfaces and non-rectangular shapes. In the first, we generate parametric spike 3D textures, and in the second, we demonstrate long curved shapes and 3D cones. A DXF file is saved and used for cutting the punchcard using a digital desktop cutting machine. Our workflow broadens the design opportunities when using punchcard-driven domestic knitting machines.