klsilves@mit.edu
For the Final week of the course, I worked with Kyle Coburn and Yihyun Lim on our Project for MIT’s 150th Anniversary FAST Student Competition. Our project creates an inhabitable landscape composed of series of cast plaster slumps on a grassy field on MITs campus.
Rendering of Potential Scale in Proposed Site
Located in the grassy corridor between Walker and Baker.
The project is an investigation of casting plaster into thin sheet latex to produce a variety organic curvatures. Plaster is used to freeze the concave and convex curves formed by latex under tensile stresses. A wooden frame with a combination of latex (0.006 cm thickness) sheet and Lycra tulle stretch fabric (additional support to thin latex during heavy plaster pours) was used as the ‘mold’. The direction of the curve and the height of each slump can be controlled by the angle in which the mold is set (when the plaster is poured) and the amount of stress applied determined by the weight of the material itself. By relying on gravity and the weight of the plaster to achieve each curvature, structural catenary and parabolic curves are achieved (allowing for lighter shell forms). The smoothness of the latex sheet was transferred to the surface quality of the cast plaster, creating a welcoming and touchable surface. Additionally, joint conditions are controlled by creating a smooth lip at each base edge creating a smooth transition between each mound.
Width, height, and angle of each slump is based upon a globally controlled scheme. Mounds vary between three different base shapes: a large, a medium (2/3 of the large), and a small (1/3 of the large). The maximum height is determined by the largest mound achievable and the final selection of the site. The landscape ramps up to direct its users towards the Charles River and/or MITs campus. We utilized the week to produce the largest slump we could to understand the scale in which we could successful work in.
Different Mound Sizes
To be able to rapidly create many slump with the same base shape, we created a jig that can be reused over and over. The directionality of the slump is controlled by the angle in which the jig is set during the casting.
Jig Design for Casting
Milled out the profile of the base using the Techno CNC. We used a 1/4″ flat head end mill to cut the desired pieces.
Frame is bulked up to create a rigid frame to support the weight of the material without warping.
Molding was put around the base edge to create a smooth transition between pieces when laid side by side. Wood putty was used to fill in any holes and grooves.
Stretch lycra and a .006 cm sheet of latex were laid over the opening and stapled into place. 3/4″ plywood was they placed around the opening to create a stable lip on which the weight of the material could rest.
Frame was assembled with a rod running through one said (behaving as the pivot axis) and bolts into holes at the desired angle.
Hydrastone plaster was mixed in a large container with 2 parts plaster to 1 part water. Sand was used as an aggregate.
Plaster was poured over the latex and the weight of the material created a slump in the material. As the plaster cured, we pulled it up the sides of the latex to create a shell. The base was scraped to create a smooth edge.
Plaster before being worked up the sides of the slump.
After allowing for the plaster to sure for 2 hours, the jig was disassembled and brought slowly to the ground. The piece was then flipped over.
We noticed a few uneven part due to working the paster a bit too much after is had become too viscous. For the next piece we will use even more material to try to achieve a much deep slump.