OVERLAY WITH A DIFFERENCE: STRONG SUPPORT-THREAD EDGE FINISH FOR TETEX TR
The full conservation treatment details are beyond the scope of this article, and only decisions relating to the purpose for and construction of the overlay will be discussed. Polyester Tetex TR was chosen as the overlay material for this artifact because it is durable, strong, and sheer, and of the colors available, the one chosen is ideal. It is also possible to hot-melt-cut the fabric to overcome raveling of straight or shaped raw edges. Typically, most textile conservators choose to use natural yarns and fabrics in conservation treatments, especially when treating items such as silk flags. In conservation today, inert synthetic materials, though less commonly considered, are used in the treatment of objects, especially if they have unique properties that, when applied, do not compromise the original. Thus, the merits of using a fabric such as Tetex TR in various applications are recognized for use by textile conservators and by conservators in other areas of the field who treat composite artifacts.
One of two battle honors (thick crests) that protrude from the flat plane of the flag, also showing tide lines
Detail of the same battle honor as in figure 3 showing splitting resulting from weakened silk, and incompatibility of materials—for example, heavy metallic thread composing the battle honors applied to fine silk ground fabric. Previous repairs are also shown.
Overlays are widely used in the conservation treatment of parts of or entire surfaces of textile artifacts that are in poor condition (Dancause 1996). Often a sheer fabric is used for the overlay, enabling one to view the extant textile underneath. However, the properties of such an overlay affect the color, pattern, and texture of the original. It is important that the overlay blend aesthetically and perhaps even compensate for loss of the remaining textile. The overlay serves to prevent further loss of the textile and, to an extent, unify uneven coloring of the original if it is stained. An illustration of this property is the previous repairs to the guidon. Where they were causing further damage, they were removed. The appearance of the flag was improved, but the ground under the repair threads had not faded to the extent of the rest of the flag. The overlay would assist to visually blend these areas to the other parts of the flag. Lastly, it is important that the overlay be light-weight, conform comfortably to the object, and be secured with a minimum of stitching or other attachment to the strongest areas of the artifact.
Specifically, in order for the overlay to lay in flat contact with the surface of this artifact, three areas of the overlay had to be hot-melt-cut away to accommodate the three-dimensional nature of the appliqué and design motifs. These three areas correspond to the exact shapes of the two battle honors and the tassel grommet. In these cutout areas, the Tetex TR was required to have reinforced hot-melt-cut edges able to withstand manipulation, enabling minimal stitching to attach the overlay to the artifact in select strong areas. The method of hot-melt-cutting had to accommodate both complex curves and square edges of the shaped design motifs. To fulfill the considerations listed above, a technique was sought that enabled the hot-melt-cut edges of the Tetex TR to be stronger than simply by hot-melt-cutting alone. A support thread, therefore, was added to the Tetex TR before hot-melt-cutting. The support thread is not melted away; rather, it stays in situ, partially fusing with the Tetex TR, thus strengthening the cut and finished edge of the fabric.
Paradoxically, Tetex TR is sheer but uncommonly strong and resistant to degradation, yet its cut and unfinished edges are weak and vulnerable to fraying. The hot-melt-cutting process alone enables the fabric to resist raveling to an extent. However, because the interstices of Tetex TR are large compared to the width of the yarns, the melded junctures are fine and remain fragile. Objects such as the guidon—having disproportionately heavy motifs adjacent to light-weight degraded silk—that require handling such as mounting or stitching require an overlay with edges adequately resistant to fraying. A support-thread edge finish on a Tetex TR overlay is more equal in strength and resistance to Tetex TR itself.
When the overlay with the support-thread edge finish on Tetex TR is stitched in place, a small, discrete, invisible stitch is taken. A deeper stitch would be needed to prevent breakage of the finish if the edge were hot-melt-cut alone. For some applications, the strength of the cut edge is less of an issue, such as when the melded edge can be tucked under another textile element. In such cases, stitches can be taken farther away from the melded edge, leaving the edge finish undisturbed. This technique was not possible for the guidon overlay.