Hello, this instructable will take you through the fun and easy process of making an audio speaker out of a paper plate. The IEEE (Institute of Electronic and Electrical Engineers) club at Iowa State University uses this project for a demonstration at local middle schools and is also a great project for high school kids learning basic physic principals, and will take about 20 minutes to complete. The paper plate speaker requires materials commonly found around the home or school and two materials that can easily be found at a craft store or online. The basic components of commercial speakers are the magnet, coil, and cone. The magnet and coil are responsible for moving the cone a small distance. The cone then transfers this small movement into sound by amplifying the air moved simply by have a larger surface area than that of the coil. For the paper plate project, a Neodymium magnet is used for the magnet, a hand wound copper coil replaces the commercial coil, and the cone is replaced by the paper plate. A list of materials follows below. The critical materials for this project are the 32 AWG copper wire (has to be enameled or coated) and the neodymium magnet; both can usually be found at a local craft store or online retailer. If you are having trouble finding the magnet, CMS magnets (www.magnet4sale.com) is a great online supplier of neodymium magnets and is the supplier of the magnet I used for this project. I have attached a direct link for the magnet I used (http://www.magnet4sale.com/On-Sale-Neodymium-Magnets-N42-Dia-1-X1-2-NdFeB-Rare-Earth-Magnets.html).

Material Lists.

1. Tape

2. Hot glue gun

3. Lighter

4. Wire cutter

5. 32 AWG copper wire (enameled)

6. C Battery

7. Neodymium Magnet 1” Diameter x ½”

8. Paper Plate

9. Three paper strips (8” x 2”)

10. Cardboard (12”x12” minimum)

Step 1: Create Paper Cylinder.

Now you will create a paper cylinder that will be used to as a form for the copper coil in the next step. Place 8”x2” paper on table and use C battery to roll paper around the battery as shown in picture 1. After rolling the paper around the battery, place a piece of tape on paper cylinder to hold its shape as shown in picture 2. Do not remove battery from paper cylinder until later steps.

Step 2: Wrap Copper Coil

Next we create the copper coil that in conjunction with the magnet will move the speaker. With the battery still in the paper cylinder, leave a 12 inch length of AWG 32 copper wire and then wrap the wire around the paper cylinder once about ¼’ from one end of the cylinder (picture 1). Now create a second wire wrap directly next to the first wrap, working toward the longer side of the cylinder, taking caution not to overlap the wires (picture 2). Continue this technique of wrapping until 50-60 wraps have been completed. Use the hot glue gun to and place a strip of glue over the wire, as shown in picture 3 to keep the wire coil from unwrapping. The finished coil is shown in picture 4.

Step 3: Glue Coil to Plate

With the creation of the coil all major componens have been created. To help the speaker function we will create a support structure out of paper strips. Take two 2X8 inch paper strips and fold them back and forth making 1 inch folds as shown in picture. These paper strips will be used to support the plate and keep it centered over the magnet durring operation. Tape one of paper strips about 4 inch from the center of the plate as shown in picture 1. Repeat on with the second strip.

Step 4: Create Plate Support Structure

Take the other two 2X8 inch paper strips and fold them back and forth making 1 inch folds as shown in picture. These paper strips will be used to support the plate and keep it centered over the magnet durring operation. Tape one of paper strips about 4 inch from the center of the plate as shown in picture 1. Repeat on with the second strip.

Step 5: Assembly of Speaker

You have made all of the necessary parts to make a functioning speaker and just need to put them together. First you will glue the Neodymium Magnet to a piece of cardboard. An old cardboard box lid or the side of a soda-pop box works great for this. Using the hot glue gun glue the magnet in the center of the cardboard, taking caution not to allow the glue to go beyond the diameter of the magnet. Next place the coil over the magnet, the coil should slide freely over the magnet. Now use a piece of tape to secure the two paper supports created in step 5 and shown in the pictures.

Step 6: Play Your Favorite Song

Now that we have the speaker assembled we will go through the steps to connect the speaker to a stereo system (amplifier). Before the speaker can be connected, the first .5 inch of coating on the coil wire leads needs to be removed. This procedure will allow an electrical connection to be made with the amplifier. The easiest way to complete this is by using a handheld lighter. Turn the lighter on and heat the first .5 inch of the wire lead detailed in picture 1; this will burn the coating off and leave a bare copper wire. Repeat with the second wire lead. Now we are ready to hear the speaker work. To connect the speaker to the amplifier take one of the leads from the coil and plug it into the red port on the back of the amplifier then plug the other lead into the black port. The ports of a simple home amplifier are shown in picture 2. I hope that the Paper Plate Speaker provides you with a simple entertaining project for your children or as a supplement to a physics curriculum.

Thank you to Hendrik De Hoog for the project idea and use of pictures.