In April 1942, the English city of Exeter was the first to be bombed during the Baedeker Blitz. Two nights of air raids led to more than 80 fatalities and significant damage to the city’s cultural centers; the Germans were intentionally targeting areas of historical significance. The Exeter Cathedral suffered damage to its south side, but from this calamity came discovery. As repair work began on the Cathedral, construction workers found 1,058 beeswax figures dating back to the 1400s hidden behind a stone canopy. Many of these pieces were fragments, but a few, including a figure of a praying woman, were intact.
Figures such as these would have been used as votive offerings to the tomb of Bishop Edmund Lacy. Because they were so delicate, the figures were stored in the Cathedral Archive for the next three-quarters of a century – until, 75 years later, technology allowed them to be brought out again. 3D technologies have led to a rebirth for cultural artifacts as delicate pieces can be digitally preserved, recreated, and even restored.
Researchers at the University of Exeter‘s Digital Humanities Lab have been 3D scanning the figures to create detailed digital reproductions, and even physical reproductions using 3D printing. The university has multiple reasons for taking on the project.
“One key aspect to the scanning project is preservation,” said Graham Fereday, the department’s research IT officer. “The original is preserved, and we can produce an accurate record of an object’s condition at a given point in time – any future degradation can be monitored.”
In addition, the team wants to create a digital collection of these items on SketchFab so that anyone can access them.
“3D scanning and web-based dissemination platforms like SketchFab give more people access to view objects that would otherwise not be available,” Fereday said. “A 3D scan is not the same as handling the actual object, but that is generally not possible anyway, because the objects we work with are often too fragile or valuable. This is much more engaging than just viewing static photographs.”
The figures were scanned using photogrammetry, taking the photographs with a Canon EOS 5D Mk3 and putting them together with Agisoft PhotoScan. This method allowed the researchers to capture every fine detail of the figures, such as the folds and buttons in the woman’s dress.
Using a MakerBot Z18 3D printer, the researchers 3D printed the scan of the praying woman, but that is the only 3D print they’ve made from the wax figurines so far.
“For projects where the main output is web-based, 3D scans embedded into a project website are all that’s required,” said Fereday. “3D-printed models that can be handled may be of interest in a museum setting where actual objects are available to view. The figure of the praying woman that we’ve printed is the most complete of the Cathedral’s collection – it was the obvious candidate to be printed. At the moment the plastic model is just an experiment in what we can do with the output from the scanning process. It may just be the first step in the process of producing a replica that is a lot closer to the original.”
They also 3D printed a replica of the Blue Boy, a cast iron statue found on Exeter’s High Street.
“The potential is well illustrated by the work we did with Exeter School on the Blue Boy,” said Fereday. “We scanned the statue, which they printed in plastic. They used the plastic model to produce a silicon mould, and then cast pewter replicas. They use these for end-of-term awards. A similar process could potentially be used to produce beeswax replicas of the votive figures.”
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