Explained | How Japan built a 3D-printed train station in six hours?

In the six hours between the departure of the night’s last train and the arrival of the morning’s first one, workers in rural Japan built an entirely new train station. It will replace a significantly bigger wooden structure that has served commuters in this remote community for more than 75 years.

The new station’s components were 3D-printed elsewhere and assembled on site last month, in what the railway’s operators say is a world first. It may look more like a shelter than a station, but building one the traditional way would have taken more than two months and cost twice as much, according to the West Japan Railway Co.

As Japan’s population ages and its workforce shrinks, the maintenance of railway infrastructure, including outdated station buildings, is a growing issue for railway operators. Rural stations with dwindling numbers of users have posed a particular challenge.

The new station, Hatsushima, is in a quiet seaside town that’s part of Arida, a 25,000-population city in Wakayama prefecture, which borders two popular tourist destinations, Osaka and Nara prefectures. The station, served by a single line with trains that run one to three times an hour, serves around 530 riders a day.

Yui Nishino, 19, uses it every day for her commute to university. She said she was surprised when she first heard that the world’s first 3D-printed station building was going to be built here.

“Watching it, the work is progressing at a speed that would be impossible with normal construction,” she said. “I hope that they can make more buildings with 3D-printing technology.”

Serendix, the construction firm that West Japan Railway hired for the project, said printing the parts and reinforcing them with concrete took seven days.

The printing was done at a factory in Kumamoto prefecture on the southwestern island of Kyushu. The parts left the factory on the morning of March 24 to be transported about 500 miles northeast by road to Hatsushima Station.

“Normally, construction takes place over several months while the trains are not running every night,” said Kunihiro Handa, a co-founder of Serendix. Construction work near commercial lines is subject to strict restrictions and is usually carried out overnight so as not to disrupt timetables.

As trucks carrying the 3D-printed parts started pulling in on a Tuesday night in late March, several dozen residents gathered to watch the first-of-its-kind initiative get underway, in a place deeply familiar to them.

Then, after the last train pulled away at 11:57 p.m., workers got busy building the new station.

In less than six hours, the preprinted parts, made of a special mortar, were assembled. They were delivered on separate trucks, and a large crane was used to lift each one down to where workers were piecing them together, just a few feet from the old station.

The new station, which measures just over 100 square feet, was completed before the first train arrived at 5:45 a.m. It is a minimalistic, white building, featuring designs that include a mandarin orange and a scabbardfish, specialties of Arida.

It still needed interior work, as well as equipment like ticket machines and transportation card readers. West Japan Railway said it expected to open the new building for use in July.

Railway officials say that they hope the station will show how service can be maintained in remote locations with new technology and fewer workers.

“We believe that the significance of this project lies in the fact that the total number of people required will be reduced greatly,” said Ryo Kawamoto, president of JR West Innovations, a venture capital unit of the rail operator.

The wooden building that the new station will replace was completed in 1948. Since 2018, it has been automated, like many smaller stations in Japan.

Toshifumi Norimatsu, 56, who manages the post office a few hundred feet away, had bittersweet feelings about the new building.

“I am a little sad about the old station being taken down,” he said. “But I would be happy if this station could become a pioneer and benefit other stations.”