Signal Boxes/Behind the Scenes

The Railway Series
Signal Boxes are buildings use to control signaling and rail points on the Island of Sodor and beyond.

Signal Boxes first appeared in The Railway Series book, Thomas the Tank Engine, which was published in 1946. Its last appearance was in Thomas and the Fat Controller's Engines, published in 1995.

Exteriors:

Model Series
In the model era, all signal boxes were constructed from MDF boxes with a sheet of resin bricks, or roof tiles, glued on with silicon moulds. Material even included resin with car body filler and clad.

Close-up models
Close-up shots of Signal Boxes were required for scenes where they had to interact with close-up scale figures.

CGI model
In 2009, the series introduced Computer-Generated Imagery (CGI) as a replacement for the show's long-standing live-action models. The Signal Boxes was recreated from scratch in CGI by Nitrogen Studios. The models were "hand-sculpted" in Maya, a 3D animation and modelling software.

According to Greg Tiernan, the CGI models are subjected to many rounds of review before they are submitted to HiT Entertainment for final input and approval.