Oscar Liébana & Adolfo Nadal



Printing with Metal
3D printing in metal is another construction-related technique to be explored for the creation of large pieces. This technology arose and developed from techniques of SLS (selective laser sintering), although its adaptation to objects of large volumes is achieved nowadays through the application of standard welding techniques like GMAW (gas metal arc welding), whether with inert gas (MIG) or active gas (MAG). As a result, new opportunities are opened for the exploration of complex geometrical forms, intricate reinforcements, temporary constructions, and advanced prefabrication systems. The objective of the MX3D project, for example, is the construction of a large-scale metal bridge in Amsterdam for 2017.

Particularly interesting are the complex pieces of steel for knots of the Kurilpa Bridge in Brisbane, designed by ARUP using additive fabrication without wastes. This technique creates individually designed, more efficient pieces, reducing costs and minimizing consumption of materials.



Prefabrication is a reality in the construction processes of developed countries, where labor has become a highly specialized and costly asset. Industry is able to manufacture all kinds of building elements in a wide range of materials and forms. The building sector, however, imposes limitations on prefabrication, on materials, and on final products, owing to its own metamorphic nature. Using molds only makes sense when the total production of pieces is very high – with the objective of diminishing the impact that designing and fabricating the molds has on the final price of each piece – or when the catalog of forms is not limited to a few geometrical standards. In this way, and because of the particular nature of construction projects, it is not possible to compete with a mass production process resembling that of the automobile industry, for example.

Javier Fuentes [MUA]. Universidad Europea de Madrid

3D printing for construction can be geared towards reducing the gap between mass and personalized fabrication, creating a middle ground between industrial and traditional construction. Though market predictions point to exponential growth, 3D printing technology only makes sense where other fabrication methods are inapplicable because of geometry or size-related restrictions; that is, a series of products and methods like complex smelting, prefabricated or monolithic structures, temporary constructions, non-structural parts, and other components that may require a high degree of personalization. Moreover, 3D printing can address the demand for quick serial production of similar but differentiated parts, such as facade panels with slight modifications. This customized fabrication is present in one-of-a-kind buildings all over the world and has been made possible by the implementation of parametric software in architecture and construction.


Javier Fuentes [MUA]. Universidad Europea de Madrid

Robotic arms have been used in the industry since 1956, the year the company Unimation launched the first four-axis robot arms, but use of them in non-standardized processes or in manufacturing industries associated with construction is new. Although there are standard formats of 3D modeling for printing that have proven useful for three-axis printers, robot arms have a specific motion system that depends on the manufacturer, which makes them hard to standardize. As a consequence, all of the world’s main robot suppliers provide integrated software and hardware solutions, and this in turn results in a large variety of new opportunities to explore the matter, especially in the construction and
building sector.



Robots can be considered simple jointed arms, composed of a series of connections and axes. Unlike other manufacturing methods, the making of six-axis robots has no inherent geometrical limitations besides their size, which is easy to enlarge through the introduction of rails of external axes. The project Space Frame (Gramazio Kohler Research, 2016) shows that it is possible to print without support material, which proves that the logic of ‘layer by layer printing’ can be surpassed when robot arms are used as a recourse or medium for 3D printing. These machines have the capacity to create spatial structures that can replace those created by other, more generic techniques. Once again, the use of appropriate materials – PLA (polylactic acis), derivatives of ABS (acrylonitrile butadiene styrene), composites similar to cement – encourages the production of life-size objects, whether for automotion, the aerospace industry, construction, or other production sectors. Of the various options available in the market, robotics is the most versatile and also the most capable of taking on many different scales.

Extruded Structures, gramaziokohler

Arquitectura Viva nº187: Spanish Solutions: Under 50 the Crisis Generation (Pp: 70-75. Vol. 187:9). Versión impresa ISSN 0214-1256.