Smudger was a narrow gauge tank engine, who worked on the Mid Sodor Railway. He was later turned into a generator.
According to Duke, Smudger was a show-off who rode roughly and often came off the rails. Duke tried to warn him to be careful, but Smudger never listened to his advice. He was finally punished by being turned into a generator and being put behind the engine shed.
Smudger was a complete show-off and often derailed, but refused to listen to advice. Duke warned him to be careful, but he took no notice until he was put in his place by being turned into a generator.
Smudger is based off of the Talyllyn Railway's Dolgoch, a Fletcher, Jennings Class Bb 0-4-0WT. Rheneas shares the same basis, but in the 1998 magazine story Duncan Has a Spill, he appears to be a freelance design.
Smudger was painted dark green with black lining. His nameplate and number are both gold. As he shared the same model as Rheneas, the inside of his cab is red. Despite being numbered on television, no toy or artwork has shown him with his number. In a rare image, Smudger's coal bunker is red.
- Season 1 - Dashing Duncan (flashback; does not speak)
- Season 2 - Trouble on the Line
- Season 4 - Duke and Smudger's Past Adventures
- Season 7 - Bertram's Discovery
- Smudger's model was recycled from Rheneas' model, and then repainted back.
- Smudger is the first character in the television series to not originally come from the Railway Series. However, his role is based on that of Stanley from Duke the Lost Engine.