Dioramas are miniature reproductions of a scene. Dioramas can be based on either historical, literary or fantastical scenes and can be made as a hobby or school assignment. The smoke generator from a model railroad engine can be used to add smoke effects to a diorama, increasing either the realism or surrealism of the scene. Adding smoke will make your diorama unique and memorable. Placing the smoke unit under a false floor or inside-part of the diorama can create several optical illusions. Depending on how the diorama is made, a false floor can either be the original diorama floor elevated to create a space below it or built into the diorama's design.
Determine the most appropriate location for smoke in the diorama. For example, if there is supposed to be a fire in the diorama's fireplace, then that should be the source of the smoke. If the smoke is intended to lay over the ground like a fog, then the source of the smoke should be the entire bottom of the diorama. Cut holes into the floor of the diorama in the appropriate places using a hobby knife.
Build a false floor on the bottom of the diorama. Attach struts of dowel rods to the underside of a lightweight diorama, creating a space 1/2 inch higher than the height of the smoke unit. Cut lengths of cardboard the same height as the rods and attach them around the outside of the diorama to cover up the struts. Leave room to insert the smoke unit in the area around the drilled holes. Heavier dioramas may need to be propose-built with a false floor because of the weight.
Place the smoke unit under the diorama close to the smoke holes. Turn on the smoke unit.
Some smoke generators may require an external power source while some may be battery powered. All model train smoke units will need to be occasionally refilled with the proper smoking liquid.