Introduction: Mini Dry-Ice Fog Machine

About: I'm Mike, from The Geek Pub. I'm a maker. I love to make things. from woodworking to electronics. Follow along with me!

Are you about to have a party? Need to setup some props for Halloween? About to put on a play at the local school or church? Then you my friend need a Dry-Ice powered Mini Fog Machine!

And I'm going to show you how to make one for less than $10.

Step 1: Watch the Video!

Even though this is a simple project, it's really helpful to watch our video. So take a second to do that, and then head on over to Step 2!

Step 2: Items Needed

You're going to to need to following items to complete your Mini-Fog Machine. You can get them all at your local big box store.

  • Small plastic container
  • 2.5" PVC Adapter
  • 2.5" PVC Pipe, 6" long
  • Computer Fan
  • 9V Battery Snap
  • 9V Battery

Note on sizes: You can make your Mini-Fog machine bigger by buying bigger components. A trash can and a box fan would make a huge fog machine for example. All you'd need then is more dry ice and more water.

Step 3: Cut Out the Holes

You'll need to cut two holes in the mini-fog machine's plastic container.

Cut the first hole in the top (the lid). Make it slightly smaller than the computer fan you purchased. Cut the second hole in the side of the plastic container. This hole will be where we thread the PVC fitting into. Make this hole smaller than the threads so that they will screw into the hole and seal it when done. Just 1/32" to 1/16" smaller should be plenty.

I used masking tape to cover the lid and sides of my mini fog machine. This allowed me to mark on the tape and then remove it when done, leaving no markings on the finished product.

You can cut the holes with anything from a razor knife or sharp scissors to a rotary tool or hole saw. I chose the rotary tool with hole cutting attachment, because I already had one.

Step 4: Attach the Fan and Outlet Pipe

Use hot glue, or CA glue ("super" glue) to glue the fan to the lid. CA glue won't hold up to moisture rich environments as long a hot glue, but it should do the job. If you bought a square computer fan, you can just use some screws and the four screw holes provided.

Screw the outlet pipe into the hole you created earlier on the side of the container. No glue is needed, but you could use some hot glue if you desire.

Once that's complete, attach the 9V battery to the 9V battery snap and twist the wires together from the snap to the fan. Red to red, black to black. If there are four wires on your fan, only use the red and black. The other two are speed controllers and not needed for this project.

Step 5: Boil a Few Cups of Water

Boil a few cups of water in the microwave. Generally 3 minutes or so.

Step 6: Add the Water and Some Dry-Ice

Pour the boiling water into the Mini-Fog Machine's container. Be very careful not to spill it as it will of course burn you badly.

Carefully, using gloves, break of some dry-ice and gently place it into the boiling water. Do NOT drop it in the water as it will splash boiling water out!

Place the lid back onto the container with the fan running,

Step 7: Enjoy the Fog!

That's it! You're mini fog machine should be making a ton of fog! Place it on the stage or behind your Halloween decorations and let the fog cover the area!

If you liked this project, you'll probably like my other projects too! So be sure to check me out here on Instructables, on my website at The Geek Pub, and over on YouTube at