The Hexagons

Summer 2014

Role: Lead Designer and Engineer

Team: Me

Skills: Structure Design, Sculpture Design

Tools: CNC Router, Machine Shop

After applying for and receiving grants for over $2K from the Council for the Arts at MIT and the MIT Art Scholars, I began work on my independent project, The Hexagons.  I sought guidance from a professor in the Architecture department to critique my development of the form of the sculpture before refining the design to minimize cost and manufacturing/assembly time.  I designed each hexagon to be assembled using only wood glue, with minimal hardware to join each hexagon to its neighbor.  I applied to display the sculpture on campus and was granted permission to install it on Eastman Court from September 2014 to September 2015.

I performed multiple form studies in CAD (Rhinoceros), foamcore, and masonite.  My initial idea was to create a honeycomb of tapered hexagonal extrusions to form either an archway, a bench, or a large play structure.  The idea of creating a huge interactive sculpture for children and adults was the most exciting to me, and I decided to pursue it.  However, I found that when I was stacking my form models, they never seemed to sit perfectly.  I ran some analysis in the CAD model and found that due to the tapering of the extrusions, each of the bottom hexagons did not share the same base plane.  Additionally, the angles between each of the six outer and six inner faces of the hexagons would not be exactly 60 degrees which would make fabrication difficult.  Ultimately, I decided to simplify the design to straight extrusions to complete the project on time.

After designing the final form, I researched materials.  I consulted with five local wood suppliers and determined that a marine-grade plywood would be ideal for this form since it is dried slowly during lamination, resulting in extremely flat sheets.  Additionally, it is weather-resistant for up to five years unsealed, and up to twenty when fully sealed.  I created a 1/2 scale model and performed various tests to determine its strength.

Next, it was time to create the full scale sculpture!  I generated 2D cut sheets in Rhinoceros and used MasterCAM to generate G Code to control the CNC router.  I CNC routed each of the six inner and six outer faces per hexagon, plus a front and back hexagonal face and an inner rib.  Using the CNC router, I was able to add precise dado cuts into each face to insert the inner rib.  Next, I cut a 60 degree angle into each face on the table saw.  With the help of my friends and family, I glued each hexagon together and sealed them with spar urethane.  Each hexagon weighs 90 pounds individually.  The only hardware in the entire sculpture are the tee nuts and bolts used to fasten each hexagon to its neighbors.

© 2019 Tara Pratap Ebsworth