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“House Divided.” All images © Rael San Fratello, shared with permission

Rael San Fratello On the Boundaries of 3D Printing and the Impact of Division

Virginia San Fratello and Ronald Rael of the eponymous studio Rael San Fratello (previously) foster a practice that’s difficult to categorize. The pair pursue projects that transcend the boundaries of design, art, technology, and craft: they continually address the implications of the U.S.-Mexico border wall, had a hand in the iconic Prada Marfa, and have constructed homes entirely through 3D printing. Although their interests are broad, Rael San Fratello is always committed to the material and structural, to recognizing everyone’s humanity, and to finding sustainable, practical ways to create a more hospitable future.

The pair spoke with Colossal managing editor Grace Ebert via email in the summer of 2022 about applying their 3D-printing practice to larger projects, the role tradition plays in their works, and how, as educators, they encourage their students to embody the same innovative, endlessly curious mindset.

This conversation has been edited.


Grace: You’ve written that Rael San Fratello doesn’t have a set philosophy and is difficult to define. That said, I’d love to know what you’re working on today and what problems or concepts you’re most concerned with at the moment, either together or separately.

Virginia: For the last several years, we have been developing methods for 3D printing and robotically extruding clay and mud in an ongoing project called MUD Frontiers, and this summer, we are focused on scaling up and applying that research in larger and more architectural applications. This is happening in two different projects, the Frontier Drive-Inn and the Lüp Brick Project.

Ronald: About Frontier Drive-Inn. In Colorado’s high alpine San Luis Valley, I’m constructing what will be the largest 3D-printed earthen building in the world—of which there are very few to begin with. However, what makes this project unique is that it is entirely constructed from local soils using traditional earthen materials and is permitted for construction as part of experimental accommodations at a historic renovated drive-in theater. This project crosses the border between land art, experiential installation, and architecture. The building is composed of eight earthen silos that frame the sky through circular oculi. The project promotes dark skies and maintains and promotes a tradition of building with earthen materials in the region. While this project is closer to land art and environmental sculpture, it makes headway towards applying additive manufacturing technology to construction using environmentally friendly materials.

Virginia: For The Lüp Brick Project, I modified my clay 3D printer for travel and am using the printer to 3D print bricks made of the local pink clay from the Lamone River that runs through Faenza, Italy, a town rich in clay deposits, pottery, and brick traditions. To create the bricks, I’m using Potterware, a software application created by Emerging Objects, that allows users to very quickly design ceramic objects for 3D printing. The software uniquely generates richly textured surfaces using waves and loops.

In the Lüp Brick Project, we are creating highly textured bricks, with a textile or basket-like surface, that can be stacked to create sculptural and artistic walls and columns made of the fired local clay. Each brick is engineered and designed to be very simple and strong and printed very quickly. This project takes advantage of local materials, easy-to-use software, and efficiencies in printing and stacking to create beautiful, sinuous, and otherwise seemingly complex surfaces and architectural assemblies.

From the Frontier Drive-Inn Project

Grace: Both of these projects utilize local materials for building. It might be as simple as wanting to use what’s available nearby, but I’m wondering if there’s a more conceptual or value-based reason to why you often gravitate toward those kinds of materials.

Virginia: Using local materials is an essential part of each project. Both of these projects are reinterpretations of traditional building materials and methods through the twenty-first-century lens of emerging technologies. In both of these projects, we are building upon historic building practices so it makes sense that we would use local and traditional materials. In southern Colorado and northern New Mexico, buildings have been made of adobe, or mud brick, for hundreds of years. In Faenza, buildings have been made of fired brick for hundreds of years. In these two projects we are using mud and clay, materials that are heavy and expensive to transport in conjunction with easy to use, lightweight, and mobile robotics.

We are setting the stage for a future where the industrialized component of the construction assembly is easily portable and can be moved to the construction site to build something much larger than itself, and the non-industrial component, the raw material, is already there to lend it’s provenance and character to the building. The combinations of new and old, industrial and non-industrial, digital and analog, are all juxtapositions that you can often find in our research and creative work.

Detail of “Sawdust Screen”

Grace: Pattern seems to play a sizeable role in your work, in part because it fulfills an aesthetic goal but also because it’s functional. When you’re beginning a project, where does pattern come in, and how does it shift throughout the process?

Virginia: We usually start our 3D-printing projects by trying to understand the possibilities of the material we are developing or using in relation to the hardware and software that we are exploring for a particular line of research or a project. Pattern tends to come into play as we delve further into a project and begin to look for contextual or cultural relationships with the material and programmatic or functional opportunities.

For example, in the “Sawdust Screen” when we were 3D printing with literal sawdust, we used a microscopic image of wood as inspiration for the porous pattern on the screen. Within the context of this project, that image felt like a relevant and suitable reference. We then realized the negative spaces created by the image and found in the pattern could be programmatic and useful because they allow for the passage of light and air, and they create opportunities for views and viewing. We used the negative spaces, or voids, in the pattern to essentially serve as openings or windows.

Another good example is the use of loops and waves when 3D printing with clay and mud. Interestingly, we don’t model the loops and waves in 3D-modeling software. We design them in the gcode, which is the software language that speaks to the 3D printer. We literally take the line of clay for a walk around and up and include the loops and waves as part of this continuous line or coil. The loops and waves give the pieces we are making increased structural integrity, which allows us to print larger forms.

Detail of the 3D-printed ceramic Lüp wall

They also allow us to create uniqueness and individuality by making very subtle and small changes to the gcode. For example, a vessel that has 50 loops will look very different from a vessel that has 100 loops and we have only made one very simple and small change to the gcode. The loops also create thickened surfaces that hold air and this is very useful for creating insulative geometries. The loopy texture on a coffee cup creates a barrier of air that will protect your hand from the heat of the hot liquid. The wavy texture that makes up some of the wall surfaces we have printed not only makes the wall thicker and stronger but also creates air pockets that offer increased insulative properties, passively protecting the interior space, created by the wall, from the cold or hot exterior.

The thing that I like most about the loops and waves is that they create a surface that looks like a textile. Interestingly, it is presumed that the first clay vessels were formed by women carrying water, pressing mud into a grass or reed basket in order to make them watertight. Eventually, these baskets were fired in earthen kilns, burning awry the grasses, and leaving the ceramic vessel with the impression of woven baskets embedded into the surface. Later, the use of woven textiles, such as baskets, became commonplace as a method for making ceramic vessels. Over time, potters pressed textiles into the surface of their clay vessels in order to decorate them, sometimes using cords, notched wheels, or other implements to make markings that mechanically replicated the appearance of a textile. We understand that the objects we create using this technique of loops and waves is in a way a continuation of this technological and cultural development and recalls those first clay pots made thousands of years ago.

Ronald: The development of the beautiful curves and loops that you find in our ceramic work was also aimed at improving the structural characteristics of clay, particularly at a large scale. If you consider how corrugating very thin metal sheets allows it to improve drastically in strength, the same is true for mud. Making corrugated patterns in a bead of 3D printed adobe allows us to make an eight-foot tall wall with only a 3-inch mud wall. Typically earthen walls are quite thick, but this innovation allows us to reconsider what is possible with mud.

“Teeter-Totter Wall” at the U.S.-Mexico border

Grace: Your “Teeter-Totter Wall” won the prestigious Beazley award back in 2021 and is part of your current shows at the ASU Art Museum and at Cooper Hewitt, among others. How has your thinking about borders, barriers, and that specific project shifted since you first planned it about a decade ago? Did these same considerations also bring “House Divided” into being?

Virginia: Like the “Teeter Totter Wall”, the “House Divided” installation at the ASU Art Museum similarly grows out of a series of drawings that began after the construction of the border wall started and the passing of the Secure Fence Act in 2006. The drawings are blueprints that illustrate typical floorplans of houses on both the U.S and Mexico sides of the border. On the U.S. side, the border wall often cuts through private property and sometimes encroaches on occupied residences, dividing neighborhoods, communities, and families. On the Mexico side, we explored the “zero setback,” which occurs when houses have been built directly up to the border wall, literally using it as the fourth wall in a room. We designed the blueprinted architectural drawings to imagine houses that would be divided by the border wall, conjoined yet separate.

The “House Divided” installation was an opportunity for us to convert our blueprints into an architectural exploration of division and togetherness where families separated by walls might live together under one roof. We proposed a scenario in which several rooms in a house would be divided by an invisible wall. We cut in half the furniture, finishes, and objects within each room when they encountered the wall. We also used different construction methods, materials, and building traditions to represent different economies, spaces, and cultural traditions that might exist in a cross-border house. For example, we used cement blocks on the Mexican side and sheetrock on the U.S. side, materials that one might typically see used in construction on either side of the border.

With this project, we wish to communicate how the wall is not only dividing places. It’s dividing people. It’s dividing families and how the unfortunate politics of the wall today is dividing children from their parents.

Virginia San Fratello

This installation felt important for us because, unlike architectural floorplans, which can be difficult for some people to read, this built-out space created a domestic scenario that everyone could “read,” or understand because we are all familiar with the contents of our homes and what makes them personal. The furniture, the art on the walls, the food on the table, and all the individual effects and items that can be found in our homes are present in the installation, and it was our hope that people would be able to relate to some of the spaces we created and would be able to understand and literally feel the bereftness, loneliness, and loss created by the division in the house. These are emotions that we all have and we all understand. With this project, we wish to communicate how the wall is not only dividing places. It’s dividing people. It’s dividing families and how the unfortunate politics of the wall today is dividing children from their parents.

To create the interior of the “House Divided,” we collaborated with BALa (Border Architecture Laboratory in Ciudad Juárez, Chihuahua), and we based the design of the house on studies of material ecologies and residential typologies that we visited on both sides of the border while conducting research for the project. We were also assisted by Marisa Fimbres, whose hometown is the border town of Agua Prieta, Sonora. The installation was curated by Brittany Corrales and fabricated by C.K. Valenti.

“House Divided”

Grace: In addition to your shared practice, you’re both educators. How does teaching impact your work?

Virginia: That’s a good question, I would actually say that for me the work impacts the teaching, however! We have done so much research developing materials and applications for 3D printing that I have been able to create a 3D-printing seminar for my design students at San Jose State University that builds on the work we do. In the seminar, I teach interior design students how to use different methods of additive manufacturing to create full-scale, end-use, products and building components, using the materials and some of the workflows that we have developed. Sometimes students design 3D-printed blocks and tiles that can be used in building interiors to create walls and partitions, and sometimes they use additive manufacturing to create objects that go in the interior such as tabletop accessories or light fixtures. The students learn the software, how to work with different types of 3D printers and materials, and are asked to imagine a very near future where products and buildings can be fabricated using 3D printers as a viable and economical manufacturing technology. I think a lot of students come into the class thinking 3D printing is a technology that is very far beyond their reach, but they leave the class understanding the process and having made something full-scale, useful, and beautiful on their own.

Ronald and I have been fortunate to find ourselves in the position of early adopters, and I believe we will continue to have the opportunity to experiment and to forge new territory in this space, but our students are the ones who will become the artists, architects, and designers that use 3D printing as a normative and ubiquitous way of making. They will be the generation that really harnesses this technology to construct the world, and I can’t wait to see what they make!


A Country is Not a House is on view at the ASU Art Museum through October 30, and Designing Peace is on view virtually at Cooper Hewitt through September 4, 2023. Find more from Rael and San Fratello on Instagram.

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