WATCH: Dan de-rails Channel 4 documentary
He was left red-faced on Friday's show
Last updated 10th Jan 2018
Last summer, Dick Strawbridge and a team of model railway enthusiasts attempted to build the longest model railway in the world, from Fort William to Inverness - a distance of 71 miles.
The programme following their progress will be shown on Channel 4 this weekend - but Dan had an awkward confession to make on Friday's show.
Watch the video for the full story.
The Biggest Little Railway in the World will be shown on Sunday 7th January at 8pm on Channel 4.