Step 1: What You Need...
1. Ordinary Styrofoam Plate
2. Sheet of regular paper
3. 2 business cards
4. A Piece of cardboard larger than the plate
5. Magnet Wire (preferably 30-32 gauge)
6. A neodymium magnet. I got mine from CMS Magnetics
7. Scotch tape
8. Hot glue
Step 2: Build the Voice Coil
1. Cut (2) 11" strips of paper about 1/2 wider than your neodymium magnet is tall. A cutting board works best. Wrap one piece of paper around the magnet and secure it with tape.
TIP: Be sure you don't tape the paper to the magnet. Only to itself.
Then wrap the other piece around the first and secure it with tape.
TIP: Be sure you don't tape the second band to the first, only to itself to secure it.
Step 3: Finish the Voice Coil
Remove the magnet and glue the paper coil in the direct center of the bottom of the paper plate. Remove the inside coil of paper. Re-insert the magnet. Using the magnet wire, start making turns, about 50-60.
TIP: Tape down the first piece so it holds as you wrap.
Try to wrap it tight. Then tape the final result securely with scotch tape. Remove the magnet.
TIP: You can use a multi-meter to check the ohms. You want to get as close to 8 ohms as possible. You must remove the enamel off the ends of the wire to make contact and the easiest way to do that is to burn it off with a lighter.
Step 4: Build the Suspension
Fold the two business cards into an accordian shape like a "W". The two cards are then placed symmetrically at opposite ends of the plate and glued down.
Step 5: Final Step
Glue the Neodymium magnet to the center of the piece of cardboard and lower the speaker assembly over the magnet. It should slide over it easily. Glue down the suspension cards to the cardboard and you are ready to test it out. Let us know if you make one and how it worked. Hope you enjoyed this Instructable.