As part of the conservation / restoration of 15 stained glass windows the sash/frame of two monumental Catherine Wheel windows were reinforced with carbon fiber (left). A Carbon Fiber reinforcing process developed specifically for this project by Full Spectrum Stained Glass and Building Restoration Inc. of Kalamazoo, Mi. added the necessary structure to support wind load and preserve intricate Keel moldings in the tracery. This restoration process allowed an important architectural element of the church to maintain its original design and materials with no visible modifications nor use of protective glazing.
Several previous attempts were made to strengthen these frames. On the exterior added reinforcing left vertical shadow lines across the entire diameter. Steel was bolted across the interior in two directions. Both attempts caused major distractions to the intended visual effect of these windows.
The windows framework was comprised of two separate layers, an inner Keel molding and an outer layer that included the glazing rabbet.
Checks, Cracks and separations prevailed in both Catherine wheel windows. The keel molding came completely off this section.
Pull tests were done before and after with satisfactory results.
Above stained glass panels had been removed for restoration. The fragile sash/frames could be carefully braced then removed and transported to a Building Restoration Inc. facility.
This example above illustrates the process of sandwiching the carbon fiber between the two frame layers.
All of the keel molding needed to be removed to complete the process.
After carbon fiber reinforcing was complete cracks and checks were injected with epoxy and other repairs made.