AL-10XX: ReCAST University of Michigan Taubman School of Architecture and Urban Planning
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Master of Architecture Thesis: 2015 Timothy Shan Sutherland John Larmor Andrew Delabovi Grant Heron Mark Knutson
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Above Ascetalyne torches were used to coat the inside of each mold with a layer of pure carbon prior to pouring the metal. The carbon acts as a lubricant, allowing the aluminum to flow more easily.
Assumptions
AL:10xx-ReCAST
Thesis, Spring 2015, Jury Citation University of Michigan Project Currently on exhibition in the THESIS HONORS PROJECTS: TOP HONORS SHOW at the Taubman College Gallery, Ann Arbor MI.
[too] are in large part the managers ” Architects processes they do not and cannot fully understand. ”
of
Reiser + Umemoto, Atlas of Novel Tectonics
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hile civilization has extracted resources from the earth for millennia, much of the energy expended in acquiring these materials still remains embedded therein. Of these materials, aluminum, now ubiquitous, was once more rare and valuable than gold. Because aluminum can be cast at relatively low temperatures, using simple equipment and inexpensive mold-making materials, it is an ideal material for a small scale industrial process where no hierarchical separation exists between designer, craftsman, and producer. Additionally, recasting existing metal requires only 3% of the energy used in smelting, and can be executed at a small scale in the likes of atelier studios and design schools. With a self-constructed foundry, we explored a design process highly dependent on tangible physical restraints, without utterly eschewing digital influences. The range of physical processes involved in the creation of a single aluminum artifact includes: wood frame constructs, sand cast molds, robotic burnishing, robotic scratching/milling, pouring molten aluminum, and post-production work. By employing the 7-axis robot at the intersection between primordial elements (sand and clay) and cutting-edge software, we navigated the gap between the digital and the analog, while still allowing for creative expression. Our research is intended to serve as a precursor to future creative manufacturing processes. Where others might intervene in the age-old process of sand casting to increase its efficiency, reliability, or economy, our intent was to produce novel effects. As we reconciled such paradoxes as the aesthetically perfect vs. imperfect, and the designed vs. the emergent, we came upon some truly unique results. Such discoveries suggest a new possible role of the architect/designer: that of the “digital craftsman” as well as the “chaperon of natural processes”.
Albertian visions of perfection and control created the modern-day Architect, driven by the need to maintain a high level of fidelity in the design and construction of buildings. This lead to standardization of design documents and other modes of representation. This marked the schism between designer and craftsman [re: designer and maker] through the 20th century, industrial processes necessitated increased reliability and consistency of the worker or maker. These technological processes have since expanded into the fields of design and architecture, allowing for precise reproduction of works, artifacts, structures, and details. As an ideal: digital fabrication has taken the place of the craftsman, allowing for perfect physical realization of any design. Digital fabrication in Architecture proliferated in the 1990's at the academic level where creativity and novelty are paramount, but are beginning to be adopted in commercial practice.
Proposal The research focuses on a historic craft: sand casting-a process that contains a high probability for imperfection (even in highly engineered industrial applications, it requires a great deal of precision and post-processing to achieve perfect reproductions). Digital tools are employed in the design of geometries, and in the translation of these geometries into the physical sand molds. During the mold making and casting process (which is done by hand) there naturally exists a degree of imperfection, which is expressed in spite of the perfection of the digitally designed/ fabricated artifact. Somewhere between the design as it is visualized in the computer and the final artifact that can be held, there is room for interesting and serendipitous imperfections to express themselves in unpredictable ways. The goal of this project is to carefully modulate these conflicting aesthetics (the perfect and the imperfect, the designed and the emergent) in a way that produces a unique object. By the merging of two production methods--one precise, one imprecise-we seek to re-position the role of the architect as the "digital craftsman", “guider of natural processes”, re: the "chaperon of process”. The proposal posits that the material (aluminum) has inherent characteristics, and while it can take literally any form in its molten state, there are certain limitations and opportunities built into the process of sand casting which will give the final artifacts structural strengths and an unreproducible form and aesthetic.
Andrew Delabovi, Grant Heron, Mark Knutson, John Larmor, Shan Sutherlan
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Above Rendering of the compiled toolpaths
[Abridged] Technical Process Following 2 months of research, a global form was generated in Rhino with considerations made based on our findings - The physical limitations of our team (ability to lift x lbs. etc.), economical limits, time, etc... The form needed to be structurally dynamic, formally interesting, logistically challenging and pose broad material demands; requiring the aluminum to perform as both a linear and surficial element. The aluminum components would be leveraged to perform as efficient structural members while simultaneously providing a medium for emergent aesthetic expression and calculated process failure. A flouted, flaring column was selected. The form was analyzed and sectioned to achieve efficiencies in production and assembly. [Max part size=3'x4'x2' or roughly a 400lb. mold) Surfaces were modeled in rhino via grasshopper and corresponding burnish toolpaths were generated using a second set of grasshopper scripts. The digital surface geometry was translated into the sand mold via a specially developed burnishing operation utilizing a robot and custom made tooling. A python-based, algorithmic code (in continued development at the University of Michigan) was used in translating toolpaths from rhino to the .src code used by the robots. Processing Scripts were adapted to generate tool paths along a generative fractal geometry for the etching and milling operations. Of these, primary tool paths were selected and optimized in rhino via grasshopper to define the boundaries of each part. A grasshopper script was developed to translate these linear toolpaths into orderedreference planes that would dictate the complex, interlocking edges of each piece. Secondary tool paths were identified and optimized based on the technical behavior of molten aluminum within a sand mold. These are milled into each mold using a robot and specialized tooling and form the distribution network for distributing aluminum throughout each part (sprew system). Tertiary tool paths are selected based on aesthetics and continuity and etched into each mold utilizing a robot and specialized tooling. These fine geometries are intentionally machined at the limit of the sand mold to perform optimally. The calculated failure at this level will produce the pseudo-organic character of the artifact.
Crawler 1 - Primary Tool Paths Defines Significant structural divisions in the form, milled by robot as sweeping, interlocking planes (swarf cuts)
Crawler 2 - Secondary Tool Paths Establishes the sprew network for distributing metal across the piece, milled by robot as tapered profiles perpendicular to the surface.
Crawler 3 - Tertiary Tool Paths Provides fortifying geometry, linking edges, sprews. Etched by robot along linear toolpaths
The final form shown in the photographs is comprised of 12 parts at a 15% failure rate. It was completed in 10 days and assembled in 11 hours. It is 14'-0" tall and weighs only 80lbs. The project was successful in producing an artifact fabricated with high degrees of precision, allowing for the rapid assembly of an extremely complex form, while emerging from that same fabrication process with an entirely unexpected, and unreproducible, aesthetic.
Below Structural Gothic traceries Organic capillaries in an oak leaf
Crawler 4 Dictates the delicate capillary geometry - has a calculated failure rate resulting in continuous surfaces. Etched along linear paths.
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Above Robot milling the "swarf cuts" around the perimeter of a single piece. A jug was built to position the molds at a 45 degree angle to accommodate limitations in the robot's articulation
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form Form Derivation
form
Funicular Structure + Hexagonal Division + Twist
Formal Unitized Component
Doubly-Curved 1/6th Vertical Surface
form Formal Division
Structural Joint Strategy
Alternating Vertical Components / 5
Integrated Swarf-Cut Joint and Structural Unit
Scripted Patterning
Swarf Cut Joint Ornamental Integration
Scale: 1� = 1’
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OPPOSITE From Top Left to Bottom Right
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1. Rejected cast aluminum automotive parts 2. Skimming slag from the crucible 3. Priming the crucible 4. Preparing the mold line 5. Mixing sodium silicate sand compound 6. Parting a mold 7. Forced CO2 curing of the molds 8. Calibrating the robot 9. Still calibrating the robot 10. Milling secondary geometry 11. Milling perimeter Swarf cuts 12. finished negative 13. Burnishing operation produces surface 14. Milling tests 15. Priming the crucible.
ABOVE From Top Left to Bottom Right
9. Mold is split 10. Primary (swarf) geometry milled into positive via robot. Standardized Recycled/Reorganized/Reprogrammed/ 1-4. Specializedparts tools and necessary 11. Secondary (sprew) geometry etched Mass production foundry supplies: fabricated Re-imagined and into positive via robot. resourced. 12. Final geometry etched and mold Post industrial waste 5. Sand Tamped into half of a mold. prepped for pour. 6. Robot burnishes surface into sand 13. Pour cups installed 7. Negative is filled and 2nd half placed 14. Sizing the molds on mold. 15. Piece anatomy 8. CO2 cures the sand mixture 16-18. Pouring
Specialized parts Craft production
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Left 2015, Taubman M.Arch Thesis Show Liberty Annex, Ann Arbor MI
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