The Octahedron – SDF2013

We’ve been looking for opportunities to share the things we’re interested in outside of this blog, especially with people who are not necessarily computational designers.

Early in the summer, we approached the committee in charge of the Seattle Design Festival and asked if we could contribute something to the September event, though at the time we weren’t quite sure what that something was.  After a few months of brainstorming, painting, cutting, and hammering we successfully installed our Octahedron Pavilion in Pioneer Square for the weekend.  It was a great event and the weather cooperated for the most part.

The design team took on fabrication and assembly of the entire structure.  This experience gave insight into the production of a large number of complex parts, tolerances, sequencing of assembly and the joys/anxieties of installation.  The project also served as a firm-wide training tool about space frame structures, parametric modeling, and digital fabrication. Full-scale prototypes were created from the outset to study connections and assembly.  The overall form emerged out of these prototypes and parametric explorations of a hexagonal grid.  The base unit of the larger form is a triangular assembly of parts which was discovered during these studies.
An octahedron is an 8-sided polyhedron that possesses the fascinating quality of appearing as various forms from different perspectives.  The sides are equilateral triangles measuring 10.5’ along an edge, each containing 9 instances of the triangular base unit.  The Octahedron is designed as a flat-pack space frame structure that is CNC cut from 1/2” plywood that is painted black on both sides with nontoxic tempera paint.  The cutting process exposes the color of the wood along the edges, creating a visual richness. Only 9 unique parts are used in the structure, but there are over 2000 of these parts.  High tolerances were necessary during fabrication to ensure all parts would fit tightly together with friction only, but not so tight that they’d break when banged together with a hammer.  Imagine traditional timber framing meets Buckminster Fuller.
The pavilion is clad with over 400 triangular MDF panels held in place with either friction or trapped due to assembly sequencing.  The inner face is painted blue, and serves as the canvas for a collection of 54 sets of CNC cut patterns generated by coworkers as part of an internal technology training exercise.  The outer face is painted black and serves as a canvas for the community to transform the appearance of the Octahedron with chalk over the course of the Design Festival.  Laser-cut miniature triangular base units were provided for festival-goers to assemble and gain an insight into the construction of the Octahedron.

In a future post, we’ll go into the how and why we cut patterns into all of the panels, the organization of the parts for cutting, the assembly process and some lessons we learned. In the meantime, we hope you enjoy our photos and timelapse video of the fabrication and assembly process.

We’d like to thank the Seattle Design Festival Committee for allowing us to take part in the festival and a special thank you to Trevor Dykstra for letting us use some of his great photos.  


  • Matt Hutchinson

    Really cool project guys – digging just about every aspect of it!

    • scrawford

      Thanks Matt. It was a really fun build and awesome to see that it actually worked! Which aspects do you think could use a little more work?

  • Matt Hutchinson

    Oh none really! Ha – I guess my wording slightly insinuated I wasn’t into all parts. Actually everything is cool and well developed from the detailing of connections (specific to CNC processes) to the ornamental patterning.

    • scrawford

      Haha. I thought I might’ve been reading too much into the wording. Nothing ever really feels done when you this involved with it so I was just wondering if there was something you thought we missed. It has been disassembled into the individual sides and we’re currently working on chalking up the entire thing for another event in November.