Behind-the-scenes snaps ranging from the 10th to 12th Seasons have emerged online.
The six previously unseen photos from Shed 10 Ltd. were posted on the model unit's website.
They show models of Skarloey, Rheneas and Billy during the makings of Wharf and Peace, Wash Behind Your Buffers and Don't Be Silly, Billy!.
A brass Thomas is seen as is the initial basis of Hank being a Challenger 4-6-6-4 in a sketch from pre-production of the 12th Series.
Led by Phillip Reeves, the Shepperton Studios based company have been involved in the TV and film industry for over 25 years.