The best made stained glass window will eventually succumb to a combination of chemical and physical forces. Wind, moisture, and the cycles of expansion and contraction inherent with temperature variations all contribute to metal fatigue. The majority of the time, it is the metal came which is compromised by these elements, not the glass itself. As this happens, these windows fall out of plane. The came begins to corrode and buckle, and pieces of glass will begin to crack under physical forces they were never intended to resist. Through traditional techniques, and a dash of modern metallurgy and chemistry, these panels can be restored. Whether a window or skylight is historically precious, or simply precious to you, these treasures can safely radiate beauty and inspiration once again.
Conservation of artwork in general, and leaded glass specifically, is an activity whose methodologies may include conservation (to arrest the deterioration of an item), restoration (to re-establish an item in its original setting), renovation (to renew an item, as far as possible), or replacement (the harmonious substitution of new material into an older item).
The key principles of any conservation strategy should be of minimum intervention and maximum reversibility.
Research and documentation are also integral parts of a complete conservation project. This includes an inquiry into the original function and history of a window, the materials and techniques used in its creation, and any past treatments as well as its current condition.
Each stained glass project must be assessed to determine whether the optimal conservation treatment is simple stabilization of structural integrity or restoration of missing elements.
The halo in this panel is composed of antique, hand-blown “flashed” glass. This material is comprised of a thin veneer of one color of glass fused to a base glass of a different color. In this case, a layer of pink has been layered over pale blue, with a gradation in the pink tone from light to dark. The piece had been painted and fired with line work and textural shading. At some point, the top piece of this halo was badly damaged. In addition to multiple cracks, tiny shards of the pink layer have flecked off, clearly visible in this photo. Our challenge was to salvage this piece by mending the cracks, as well as filling the space left by the irretrievable shards.
The piece was stabilized during the removal and dismantling process, in order to retain even the smallest remaining shards. The glass was cleaned by hand to remove dirt and old putty, and edge glued on fracture lines using HXTAL NYL-1, a two-part, non-yellowing epoxy resin.
The epoxy is held in place with dams of clay and a substrate of waxed paper. After it has fully cured, a mixture of HXTAL and Orasol dyes (a transparent pigment) was applied in a thin layer over the missing areas to mimic the missing flash. The piece is then ready to be releaded into the panel
The halo, re-glazed into the restored panel.