The Heinz Architectural Center at the Carnegie Museum of Art houses a collection of nearly 6,000 architectural objects, models, and works on paper. A recent acquisition for the exhibition The Fabricated Landscape (2021) was the large-scale architectural model, The Grand Interior (2017), by Barcelona/New York based architectural collective MAIO. Fabricated for the 2017 Chicago Architecture Biennial, the 6 ½ x 5 ½ ft. model serves to illustrate the ways in which domestic spaces both interconnect and distinguish themselves by the objects that inhabit them, rather than the traditional architectural structures.
Inherent vice in the model’s construction presented several impediments to its safe exhibition. Fabricated from a single sheet of mirrored (poly)methyl methacrylate based plastic cradled in a softwood frame and onto which nearly 150 pink painted miniature objects were adhered, the model arrived with nearly half of these components completely or partially detached. Competing solvent sensitivities of the materials prevented a more straightforward approach to securing them: the miniatures—commercially-manufactured ceramic, metal, wood, and polystyrene based plastic forms airbrushed with powder-pink paint, and affixed with cyanoacrylate based adhesive—were sensitive to all solvents tested with the exception of water and mineral spirits. The pink paint covering each of the miniatures was matte and weakly-bound both to itself and to most of the surfaces it was applied, also limiting the methods and materials that could be used for repair. Most challenging of all, the model’s overall width exceeded that of any its potential pathways to the exhibition space, which meant that it would need to be transported by hand for several minutes while tilted at an angle.
The treatment approach began with materials analysis to guide decision-making in the fabrication of experimental mock-ups. Optical and digital microscopy, Fourier-transform infrared spectroscopy, and x-ray fluorescence spectroscopy were used to identify the primary polymers in the paint, adhesives, and substrates of the synthetic materials present, as well as to better understand the initial mechanism of failure. The results of solubility testing and knowledge of Hildebrand solubility parameters led to a decision to use an adhesive system based on either water-deliverable/water-reversible and/or MS-deliverable/MS-reversible adhesives. As a result, several adhesives less commonly used for structural repairs—such as Aquazol, Jade R, Regalrez, Ethulose 400, and Paraloids B-67 and F10—were tested, beginning with mock-ups, for their ability to withstand gravitational forces applied to the model’s tallest, thinnest components when tilted. Criteria for evaluation included not only the system’s strength, but also its ability to be reversed without major losses to the very fragile paint. In the end, a system combining an Aquazol 50 consolidation layer and a bonding layer of Jade R water-reactivatable adhesive, allowed the repaired model to be safely transported at a nearly 90-degree angle for installation. As The Grand Interior represents only some of the materials issues in the museum’s growing collection of modern and contemporary architectural models and ephemera, the conservators’ evolving approaches to the preservation of the Carnegie Museum of Art’s architectural models in general will also be discussed.