Fog Chiller Directions

Ominous, chilly fog surrounds this poor child's feet.

Something about ground fog twining around your feet is more menacing than a bank of fog or smoke. Ground fog, because it never obscures anyone's view, is also a safer theatrical effect than billowing clouds from a fog machine. For this reason, ground fog appears frequently in high school productions and Halloween displays. Artificial fog that billows and fog that hugs the ground both emanate from a fog machine. The machine heats a solution of glycerin or glycol and water called "fog juice" and blows it into the atmosphere. Ground fog is the result of chilling that hot haze with a device called a fog chiller.

Things You'll Need

• 3.5-inch diameter PVC pipe
• Hacksaw
• 3.5-inch to 2-inch PVC adapter
• PVC cement
• 2 90-degree PVC elbows
• Closable plastic bin
• Grease pencil
• Electric drill
• 1/2-inch drill bit
• Caulk
• Duct tape
• Wire mesh
• Scissors
• 2 4-inch hose clamps
• Flathead screwdriver
• Ice

Instructions

1. Cut two 4-inch lengths from a 3.5-inch diameter piece of PVC pipe with a hacksaw.

2. Cut two 6-inch lengths from a 3.5-inch diameter piece of PVC pipe with a hacksaw.

3. Glue a 3.5-inch diameter to 2-inch diameter PVC adapter section to one of the 4-inch lengths of 3.5-inch diameter PVC pipe with PVC cement.

4. Glue the other end of that 3.5-inch-diameter pipe to a 3.5-inch-diameter, 90-degree PVC elbow with PVC cement.

5. Glue the second 4-inch length of 3.5-inch-diameter PVC pipe to the opposite end of the 90-degree PVC elbow with PVC cement.

6. Glue a second 3.5-inch-diameter, 90-degree PVC elbow to the second 4-inch length of 3.5-inch-diameter PVC pipe with PVC cement; the PVC elbows should form a U with the two ends of the PVC joint pointing in the same direction.

7. Attach the 2-inch diameter end of the U to the fog machine exhaust pipe.

8. Set the fog machine on top of a closable plastic bin.

9. Arrange the fog machine on top of the plastic bin so that the open, 3.5-inch end of the PVC U-shaped joint butts against one end of the plastic bin. The 3.5 inch end of the PVC U-shaped joint should be in direct contact with one end of the plastic bin so you can exactly mark where to cut a 3.5-inch hole in the end of the plastic bin.

10. Mark the location where the PVC pipe meets the end of the plastic bin by tracing a circle around the end of the pipe with a grease pencil.

11. Remove the fog machine and PVC U-shaped joint.

12. Drill a 1/2-inch-wide hole anywhere inside the circle you just drew with an electric drill and a 1/2-inch drill bit.

13. Cut a 3.5-inch-diameter round hole in the end of the plastic bin with a portable jig saw using the 3.5-inch circle you drew as a guide.

14. Repeat to cut a 3.5-inch-diameter round hole in the opposite end of the plastic bin.

15. Insert one 6-inch-long piece of PVC pipe into each of the two holes in the ends of the closable plastic bin. Approximately 3 inches of each pipe will be inside the bin and approximately 3 inches will be outside the bin.

16. Secure the pipes in the holes with caulk and duct tape. Extrude or daub caulk around the joint where each pipe enters the plastic bin. Wrap approximately 1 inch of a piece of duct tape, which must be long enough to cover the circumference the pipe, around the pipe and stick the remainder of that width of duct tape to the end of the plastic bin. The duct tape should cover the caulk.

17. Cut a piece of wire mesh so that the mesh is the same length as the inside length of the plastic bin with scissors.

18. Roll the wire mesh into a 3.5-inch-diameter tube.

19. Attach each end of the wire mesh tube to one of the 6-inch-long PVC pipes that extend into the plastic bin.

20. Secure the mesh tube to the PVC pipes with hose clamps using a flathead screwdriver.

21. Fill the plastic bin with enough ice to cover the mesh tube and close it.

22. Attach the fog machine exhaust to the 2-inch diameter end of the PVC U. This time, instead of simply measuring the distance between the fog machine exhaust and the correct place to cut a hole in the end of the bin, you will actually use the fog machine and the almost completely assembled fog chiller.

23. Attach the 3.5-inch-diameter end of the "U" to one of the pipes on the ends of the plastic bin.

24. Start the fog machine.

References

• LightForm Productions, Inc.; Build Your Own Fog Chiller; 2009