Are You Suprised ? s22

Bone Shaker Construction

TEACHER ONLY

Lets build a bone shaker!!! This is probably one of the coolest demos that you can do in a middle school EMAG unit. Follow these steps:

1. Buy two massive ring-shaped speaker magnets. I have used 6” diameter neodymium and ferrite magnets. The neodymium are a lot more powerful, but can be very dangerous is not secured. The force of attraction between them could crush a finger.

2. Build a STONG magnet carriage. It needs to keep the magnets about 1.5 to 2 inches apart and leave room in the center for a wood dowel with a coil of wire around it.

3. Attach the two ring magnets to either side of the carriage. The magnets should be attracting each other. Screw the magnets in place as shown below.

4. Cut a wood dowel (use a diameter that you can get a drinking straw around) to about 12 to 16 inches. Take high gauge (thin) magnetic wire and wind it around the dowel until it is a little less than two inches in diameter (just fits in the carriage) and 3 to 4 inches in length. Yes, this is a lot of wire, but the more wire, the more bone shaking. Leave the two ends free for connection.

5. Sand the free ends.

6. Put the dowel wrapping in wire into the carriage and connect it to a stereo and turn it on. If the free end of the dowel starts vibrating violently, you did well.

7. If nothing happens, double check the connections… if still nothing, you may have to increase or decrease the number of coils. Most speakers are rated at 8 ohms of resistance and you may need to make some small adjustments. That being said, I’ve only encountered one stereo that wouldn’t drive one of these.