Parametric Kerf

Parametric Kerf is an exploration of laser-cut lattice hinges. Patterns are parametrically generated along a 3D surface, then flattened to be laser-cut. Kerf-bending is the process of making relief cuts in a sheet wood to allow it to bend along a curve. Lattice hinges take that concept but are through-cuts made with a laser-cutter or cnc machine. The staggered pattern of cuts create thin elements that act as torsion springs within the material. A particular curve can be formulated using a few parameters: spring length, spring width, and material thickness. There is great information on this concept here

Parametric kerf takes this concept and parametrically applies it to a 3d surface. Lattice hinges only work with curvature in one direction, meaning only developable surfaces. This curvature can be measured in Grasshopper. Using the curvature data and the material thickness, lattice hinges can be parametrically applied and flattened to a 2d drawing.

We then explored a variety of patterns to find the optimal spring geometry. We looked for ways to reduce stress concentration as well as ways to possibly change the direction of the bend.

Our good friend Arthur Mamou-Mani used the same principals to create his Wooden Waves installation, building on the open source information.

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A step by step explanation with source files is available on Instructables and a project utilizing the technique called Bloom lamp seen here