3D printed replicas of three Buddhist statues from the Yungang Grottoes in China are currently on display in Qingdao, eastern China, nearly 1,000km away – thanks to 3D printing technology. The 1,500-year-old grottoes were determined to be at risk from weathering and erosion.
Statues in Danger
Located in the city of Datong, the Yungang Grottoes are a UNESCO world heritage site with 252 caves and niches. The grottoes contain over 51,000 Buddhist statues carved into golden sandstone cliffs. However, they are at risk of erosion due to the open-air setting and high air pollution.
“Even today, scientists are unable to stop the ageing of the grottoes using chemical or physical methods,” said Zhejiang University archaeology professor Li Zhirong. “The best way to protect the grottoes is to preserve their information in a scientific, comprehensive and authentic way.”
Conservation with 3D Printing
A two-year programme was jointly launched with the Yungang Grottoes Research Institute, Qingdao Publishing Group and Zhejiang University. Researchers scanned three of the statues and collected about 10,000 photos of the caves to build full 3D models. The models were then 3D printed in parts at a workshop in Shenzhen.
20 sets of large-scale 3D printers were used in synchronous production, and a total of 842 pieces were produced. These 3D printed parts were then assembled and post-processed including filling with foam and patchwork. 10 tonnes of support structure was used.
“The colour was first painted automatically by machines. Then artists from Yungang added colour in detail,” said Diao Changyu of Zhejiang University.
These replicas measured six, ten and six metres high respectively. The margin of error between the original 10-metre statue and the replica was less than 5 millimetres.
The on-site assembly construction lasted three months before it was revealed to the public.
One of the many advantages of using 3D printing technology is its ability to preserve heritage at risk and keep history alive.
This technology has been used to conserve the remains of the Bamiyan Buddhas in Afghanistan, create replicas of Japanese Buddhist statues or solve archaeological mysteries such as recovering and identifying badly damaged stone tablets.
“This is the first large-scale relic project to use 3D printing in the world, marking a breakthrough in material strength, block assembly and engineering installation of large-scale stone artefacts in China,” Changyu said.
They will move on to work on replicating other artefacts at risk and two other caves from the Yungang Grottoes.
Visitors can still visit the Yungang Grottoes in Datong, north-western China to view the original statues.