Salty/Behind the Scenes

Gauge 1 model
Salty's model was built as a British Railways Class 07. It was built to approximately 1/32 scale and designed to run on gauge 1 track. 8 different facial expressions were sculpted for Stanley. The faces were first sculpted in clay, and from that resin casts were made using a silicone mold. The model body was made from brass. While only one body was made, two complete chassis' were constructed from scratch (CNC). The chasses had two motors, both powered by electricity from the track via the pickups on the metal wheels. The main motor powered the wheels, while the second motor (located at the back) powered an inside piston for the smoke mechanism.

The eye mechanism had two servos, one for up and down movement and one for left and right movement. The up/down servo was attached to the body. The left/right servo had a rod attached to the arm, which connected to a bracket. The eye balls were coupled to the bracket, and locked in by the face-plate, so whenever the servos were powered, the eye balls would move however the crew member desired.

Close-up model
close-up shots of Salty's cab was required for scenes in where he 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 following year, Salty was recreated from scratch in CGI by Nitrogen Studios. His model was "hand-sculpted" in Maya, a 3D animation and modelling software.[2]

Photographs of Salty's Gauge 1 model were used for referencing. According to Greg Tiernan, every detail of the original television series models for each character is carefully reproduced in the CGI model. The models are subjected to many rounds of review before they are submitted to HiT Entertainment for final input and approval.[2]

Satly has had modifications throughout the CGI series. These include:


 * Misty Island Rescue:
 * His cap brim became shorter
 * He gained a permanent tail-lamp.
 * His buffers became less rusty and weathered.
 * His face became larger.
 * Day of the Diesels:
 * His horn sound changed to Derek's at regular pitch.
 * Tale of the Brave:
 * He gained a permanent lamp.
 * Series 19:
 * His cap brim became longer again.