The works in Christian Rudolph's "Tektonit" (tectonite) series are the result of playful experiments, which the artist initially conducts using paper models.1 In an abstraction process, he separates geometric surfaces - usually trapezes, but also ovals and ellipses - deforming them, reassembling them, and transferring the results into wall reliefs made of four-millimeter thick aluminum sheets. The surfaces and ridged seams of the fragments are first sanded by hand with extreme precision, after which the relief surface is painted with a coat of monochrome paint as many as a dozen times. The painted surface is then carefully sanded until it has reached a uniform and velvety matt quality. It is only when examined up close that the traces of this process are revealed in the fine scratches on the paint. As with Christian Rudolph’s other works, in the "Tektonit" series the artistic and the analytical-technical approaches are of equal importance, constituting the two anchor points of his sculptural oeuvre.
The name of the "Tektonit" series itself reveals qualities about Christian Rudolph’s artistic reference points. The geological concept of tectonics refers to the structure and movement of the earth's crust. Rudolph cleverly uses the term here also as an allusion to the inner structure of his works.2 In the case of the wall reliefs composed of two or more parts, opposing motions are sometimes created, depending on the type of incisions on the base surface. The different “vibrations” meet at the seams and form “edges” that are reminiscent of abstracted geological or tectonic distortions.
But how do these wall reliefs affect the viewer in their appearance? What are the distinguishing characteristics that define them as a series, as the results of a single artistic idea or concept? Sculpturally the works of the "Tektonit" series are wall objects, characterized by an elaborate interplay of spatial distortion, flexibility, and color. They testify to Christian Rudolph's esteem for geometry and his fruitful use of its vocabulary in his artistic work. To this end, he draws on a wide range of reference systems, including the historical positions of constructivist and concrete art - artistic expressions that continue to influence our world, especially through architecture and design. Two key features are at the heart of Christian Rudolph’s conceptualization of the "Tektonit" works: the plastic shaping of the surface and Rudolph's decision to use color on these wall reliefs. These two aspects of the series will be examined in more detail in the following paragraphs.
Regarded from an art historical perspective, the fold - as a detail in a broader context - conveyed narrative elements. The folding motif always suggested more than a purely representational reproduction of individual folds. Depending on their manifestation, folding systems assumed a representative function for abstract content or underlined the narrative character of a figurative representation. It was only with the advent of the artistic avant-garde at the beginning of the 20th century and with the developments following World War Two (Concrete Art, Radical Painting, Minimal Art) that the fold became a theme in non-representational art. In Pablo Picasso's assemblages - created from 1912 onward - folds were no longer related to, for example, folds in drapery or skin, but, rather, became tools for artists in their pursuit of rendering two-dimensional materials three-dimensional. In 1914 Vladimir Tatlin made the radical shift from figurative to non-representational sculpture. He reduced Picasso’s idea to its essence: the plane’s growth and development into the three-dimensional. With his “picture reliefs”, Tatlin created an independent sculptural concept. In contrast to Picasso, he completely rejected real motifs. The glass, wood, and folded metal fragments Tatlin staggered and superimposed in rooms represent nothing, and are simply material forms in space. The artist thereby consciously overcame the imaginary spatial effect that is characteristic of Picasso’s material metamorphoses.3 In their “Realistic Manifesto” published in 1920, the brothers Naum Gabo and Antoine Pevsner declared their intention to “divorce the volume of the sculptural from the mass”.4 In 1949, not long after the end of World War Two, the fundamental message of Max Bill’s manifesto was “(…) abstract ideas are rendered visible in concrete form”.5
In addition to color and form, Tatlin also declared space, light, and movement to be creative mediums, thereby including sculpture. Since the 1960s, numerous artists have experimented with a wide variety of materials by folding their surfaces, thus focusing on the issue of materiality. At the end of the 1960s, Richard Serra listed "to fold" in third place on his “Verb List” (1967/68)6, in which he named all activities and techniques involved in the production of his sculptural work. In different ways both artists emphasize that the physicality of sculpture is no longer primarily determined by three-dimensional, molded, or sculptured volumes but, rather, that a sculpture exists as a complex spatial construct in equal parts out of planes, lines, and space. Yet, while the works of Max Bill and Richard Serra are characterized by ideas in the Platonic sense, i.e., by ideas that illustrate original, fundamental, universal, and thus objective principals and concepts, Christian Rudolph’s “Tektonit” works do not follow any mathematical or logical principals in their variations and variants. They are instead the result of a subjective exploration and design process; the result of an idea; an invention.
The second factor characterizing Christian Rudolph's "Tektonit" series is his use of color, i.e., the medium of painting, or more precisely color painting, which is to be understood as a generic concept, as in the case of portrait or landscape painting, meaning that here color itself is the object of representation and not merely the medium of representation. Color painting depicts color itself and nothing else, in as far as color is a visual reality with specific qualities that are justified by the fact that color is not simply an arbitrary medium, but a visually effective source of energy. Color painting explores and exploits the energetic potential of color. Monochrome painting is a special case that deals with the problem of color representation by reducing the range of color to one, whereby the emphasis is shifted from the appearance of color to the material quality of the color itself. The fundamental realization that color is "concrete" was already clearly formulated by Theo van Doesburg in his "Manifesto of Concrete Art", published in 1930:"Concrete painting, not abstract, because nothing is more concrete, nothing is more real than a line, a color, a surface. (...) In painting, nothing is true except color. Color is the constant energy, determined by its contrast to another color. Color is the basic substance of painting; it signifies nothing but itself. (...) Painting is a means to visually realizing thoughts: every picture is a color thought".7
Van Doesburg's understanding of an art work as the concrete form of an idea, however, ignores the irrational nature of color by placing it under the primacy of an idea. Thus, in principle, van Doesburg denies the validity of his own belief in the energizing potential of color ("constant energy"), and ignores the fact that each person associates his or her own idea with a color. Every "color idea" thus evades the rational logic from the outset. More than 30 years later, in the early 1960s, the energetic potential of Josef Albers’s concrete colors was again placed at the center of artistic debate. Albers recognized that color is never isolated, but always occurs in relation to something and cannot be subordinated to any idea. Rather, colors express their own laws, which cannot be rationally justified or even ascertained. Color cannot be grasped, understood, or even precisely described by reason alone, and its meaning differs from observer to observer. Albers's basic realization is justifiably, “Color is the most relative medium in the world”.8