Qty-Materials-Where to purchase
2- 5/8" x 2'x 2' Boards or particle boards -Lowes
1 -Broan Bathroom Fan (the one around $20) -Lowes
1 -Broan Adjustable Fan Switch (located with fans) -Lowes
4 -18"x 24" Plexiglass Panels -Lowes
1- 2"x 3" Area Drain -Lowes
3 -7/8"x 48" Dowels- Lowes
3 -10'x 3/4"x 1/2" woodstrips- Lowes
24-5/8"x 3"x 3" wood squares OR 8- 2"x 3"x 3" wood blocks -Lowes
2- 3/4"x 10 1/2"x 4 1/2" boards -Lowes
1- Rubbermaid Large Trashcan with a flat top -Lowes or Home Dep.
1- PVC Male Fitting with threads 1 1/2"- Lowes
1- PVC Female Fitting with threads 1 1/2" -Lowes
1- Switch or outlet box to hold the switch -Lowes
1 -Power cord- Lowes
1- Supurr-Flex Flexible Duct 6"x 20' -Home Depot
1- L-shaped or straight Radiator Hose 2" (inside diameter) -any auto parts store
1- Fog Machine try music stores, stage and lighting effects suppliers, or internet (search for fog machines)
1- Fog Juice -Same place as the fog machine
1- Velcro strips -Walmart in craft area
3 -Cans of spray paint (flat black) -Walmart or Lowes
1 -Twin bed sheet (black)- Walmart
1- Large bath towel -Walmart
1- wood glue -Lowes
1- Pack of thumbtacks -Walmart
I have listed the places where I found the materials, and hopefully this will help you find your materials in only two or three stops.
When buying your fan and switch, make sure they are compatible by checking the model number guide located in the store. I recommend using the switch that is made to go with the fan you buy. Sometimes it is easier to pay a little more money than to make a return. Also, make sure that the switch will fit the switch box.
When buying the PVC fittings make sure they will screw together. Double check everything before leaving the store.
I highly recommend that you study the pictures in this guide very
closely before shopping so that you get an idea of what you are buying
and how the parts work together.
Cuts to Make
In the 2'x 2' boards, cut a circle 5 1/2" diameter in the center. Before cutting, check the measurements of the area drain and the fan that you bought to make sure the measurements are correct. If they are not correct, go ahead and make any adjustments needed.
Drill a hole 7/8" through the center of the wood squares or wood blocks (which ever your are using).
Cut 12 wood strips 12" long.
Cut 4 wood strips 11" long.
Cut 4 dowels 24" long.
Cut a circle 4 7/8" diameter in the center of the trashcan lid. Before making this cut, check to make sure the area drain measurements are correct for this cut. This is a cut that is better to make too small; since you can use a knife to make it larger if needed.
Cut a circle 1 7/8" diameter at the bottom side of the trash can. The height from the bottom will depend on the height the nozzle of the fog machine. Make the cut so that the fog will shoot straight into the trashcan.
If you bought an L-shaped radiator hose, cut off the longest end. If you got a straight hose, no cutting is necessary.
You will probably need to sand the ends of the dowels to make them slide better.
Putting It Together
Glue and nail 3 wood squares together. Do the rest of the squares the same way; which will result in 8 wood blocks. If you found wood blocks, this step is already finished.
Glue and nail the wood blocks on the four corners of the 2'x 2' boards.
Check to see if the dowels slide easily into the holes in the wood blocks; if not, more sanding is required.
Locate the wood strips. These strips will make a track for the plexiglass panels to slide through. Using two 12" strips and two 11" strips, make a square around the hole that was cut into the 2'x 2' boards (both boards). The 11" strips will go between the 12" strips and the ½" width of the 12" strips will compensate for the missing inch of the 11" strips; resulting in a perfect square. Check for equal measurements from each side of the board. This will confirm that the square is centered. Glue and nail the strips to the boards.
Using the remaining 12" wood strips, place them around the all four sides of the squares. The distance of placement will depend on the thickness of your plexiglass. Check to see if the plexiglass will clear the four corners before securing the remaining strips. If the strips are to long, shave off the ends so that the plexiglass will slide easily past each corner. Now glue and nail the strips.
The actual chamber part is now complete. Slide the dowels into the wood blocks at each corner of the 2'x 2' (which I will now call top and bottom boards). Put the top board on top of the dowels and slide them in also. Now try sliding the plexiglass panels in their tracks. If they are stiff, you can put coins or washers into the wood block holes; which will mimic slightly longer dowels. Put as many washers or coins in as needed until the panels slide with ease. When you made the cuts on the dowels, your saw blade cut off wood about the width of a coin; therefore, if you are making this adjustment now, you probably did not make any mistakes on the cut.
Now it is time to secure the fan on the top board. If you bought the same fan as I, your fan will have trap doors in the top. I chose to remove these doors in order to reduce friction with the airflow. Make sure that you place the fan so that the airflow is blowing out of the chamber. Center the fan over the hole that is in the top board (on top of the board). Glue and nail the 10 ½" x 4 ½" boards together so that they form an "L" (see the picture). This will anchor the fan to the top board. Glue and nail the "L" board to the top board. Now attach the fan to the "L" board.
Attach the switch box to the top board.
Make all electrical connections following the instructions that came with the fan and adjustable fan switch.
Secure the switch to the switch box.
Screw the male and female PVC fittings together through the hole cut at the bottom of the trashcan. Put the top on the trashcan.
Place the chamber over the center of the trashcan so that the holes line up. Place the area drain over and through the holes.
Slide the radiator hose over the end of the PVC fitting.
Slide the radiator hose over the nozzle of the fog machine.
When placing the plexiglass panels in their tracks, slide them so that there is an opening at the right side of each side of the chamber. This will create cyclonic rotation (counterclockwise) for the northern hemisphere. To create anticyclonic rotation, do just the opposite as mentioned above.
Place the flexible duct over the top of the fan. Use the velcro strips after painting to secure the duct to the fan; otherwise the duct will come off when stretching to a nearby window. Velcro is attached to the duct by cutting slits at the edge of the duct (see picture).
If everything is functioning correctly, you are now ready to paint the chamber. Remove the chamber from the trashcan and remove the plexiglass panels. I would advise covering the openings to the fan and covering the switch. Take the chamber apart to do the pain job. Make sure you do not paint the ends of the dowels or you may have to sand the ends again. Cover the ends with masking tape before painting. Also cover the holes in the blocks before painting. Do not forget to paint the area drain. I recommend painting the chamber black in order to maximize visibility of the vortex.
After painting and reassembling, tack (using thumbtacks) the bed sheet around the bottom board to create a curtain to hide the trashcan.
Tack the black towel on the back of the top board to create a dark backdrop; which will maximize visibility of the vortex. You may want to add a clip-on light to shine through the chamber.
Safety Information
Be sure to follow all instructions closely that comes with the materials. There are important safety issues you should know; especially with the fog machine and the fan/fan switch connections.
The fog machine is the same machine used at rock concerts and haunted houses. The fog is FDA approved, and is harmless when well ventilated. But be advised that it is possible that someone with respiratory problems, asthma, or allergies may react to the fog. The fog machine can fog up a medium or small room in less than five minutes. Large rooms like a gym or auditorium will take longer. Make sure there is sufficient ventilation.
Also, the nozzle of the fog machine gets very hot. The fog that comes out at the nozzle is as hot as steam. This is why a radiator hose is used to transport the fog to the trashcan. The trashcan serves two purposes: 1. As a holding tank for the fog, and 2. As a stand for the chamber. Because of high temperatures, be sure the sheet clears the fog machine.
An alternative to using a fog machine would be using a steam cooker
or dry ice. Both can be more dangerous. You already know the dangers of
a steam cooker. Dry ice can instantly freeze skin if contact is made; however,
the fog that is produced dissipates rapidly making it safer for small room
demonstrations and no ventilation is required. If you choose to use dry
ice, simply bypass all instructions regarding the trashcan, fog machine,
male/female fittings, the cut made on the bottom board, and the flexible
duct. The chamber can be placed on a table. A pie pan can hold water and
be placed in the center of the bottom board. Dropping small pieces of dry
ice into water will create fog. Use thick gloves when handling dry ice.
Functions
The fog makes the vortex visible.
Black paint and black colors help maximize visibility of the vortex.
The trashcan serves as a fog holding tank and as a stand for the chamber.
The radiator hose can withstand high temperature.
The adjustable fan switch allows variable wind speeds.
The chamber is designed for easy assembly for transport.
The fan creates an updraft which is essential for tornado development.
Styrofoam represents missiles or flying debris (debris cloud).
Fog represents the condensation funnel.
Tips
In transport, use the bath towel and sheet to protect the plexiglass panels from scratches.
Use small pieces of styrofoam to create a debris cloud.
Experiment sliding the plexiglass panels to change the shape of the vortex.
Wipe fog residue from the inside of the fan.
