Written by Emily Wroczynski
The Grand Isle private train car was what hooked me when I came to interview about a potential graduate internship at Shelburne Museum in conservation. The interior is a fascinating mix of different generations of restoration and renovation with different materials including wood, paint, metal, and textiles. My project has focused on the decorative cove panels throughout the car, where the paint has been dramatically lifting off of the surface.
I took 26 physical samples (about the surface area of a small finger nail) through the depth of the paint layers from representative areas on various panels and comparable molding. Examination of the cross sections under the microscope in the conservation lab at Shelburne Museum revealed that all the panels share the same decorative history, but the remaining layers do not go back as far as when the car was first built (c. 1899).
Further analysis, Scanning Electron Microscopy- Energy Dispersive X-ray Spectroscopy and Raman spectroscopy, was performed on some samples in partnership with the Winterthur Museum and Middlebury College to further understand why the paint was failing as well as identify specific materials that could help relatively date the historical paint campaigns.
False-color elemental mapping over the cross section samples demonstrates the changing trends in commercial paints in the 20th century. Despite the attachment to excellent working properties and hiding power of lead white, painters were well-aware of the hazardous health effects of lead in the early 20th century. By the 1930s, alternative white pigments such as lithopone and zinc white had almost entirely replaced lead white for interior house painting. The upper most layers in the private car samples also revealed a combination of different filler materials, which can be associated with paint formulations after 1945. The increased magnification used at Middlebury College provided evidence on the bottom of some of the samples of sand particles, likely residue from sandblasting preparation of panels before painting/repainting, which was common practice in the railroad industry in the early 20th century.
My conservation colleagues and I are stabilizing and preserving large representative areas of the historic paint under a protective coating, on top of which Museum painters will apply fresh paint to match a historic layer found on the panels.