"I kept buying bits and pieces and putting them in the cupboard until I had time to build them."
About five years ago, Smith joined the Tauranga Model Railway Club, which helped him to build a replica of the Katikati Railway Station before it closed in 1978.
"It is not just about the trains, it is about creating a scene. I think that is really important," he said.
"I love trains ... the smell of the hot oil and burning coal."
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Show organiser Rob Thomson said about 12 model train displays were on show this weekend.
Thomson said the main attraction was the club's newest layout, which was designed to give two circuits for two different prototypes on one model.
One circuit shows a model version of the Katikati Railway Station, which he said took club members about a year to complete.
The model scene started at the Tauranga end at the Henry Rd road bridge, with the line crossing the Uretara Stream, through the station yard, under the state highway bridge and nearby Mulgan Rd bridge before heading to Athenree.
The English layout included two imaginary stations based on real-life junctions.
Station one was created on a cross-country line between Kidderminster and Birmingham, located in the West Midlands near the Severn Valley. Station two was based on the town of Stourbridge.
However, the model was not yet complete. "There is no such thing as a finished model," Thomson said. "We are always working on them."
Thomson said model train enthusiasts had come from all over New Zealand, including Cambridge, Hamilton, Napier, Bulls and Tauranga, to show off their displays.
Neil Denby's granddaughters Christina Denby, 11, and Stephanie Denby, 12, and niece Olivia Neal, 10, had come along to help drive the model trains.
"They have operated the layout for two days to take the pressure off the old men," he laughed. "They love it. It is so much fun for the kids."