How to Make Magnets With a Coil & an Iron Bar
- 1). Unspool a bit of copper wire from your spool. Once unspooled, don't cut it, but instead, drape 6 inches of the wire down from the bottom end of your metal bar (holding the metal bar upright). Let it hang there and don't touch it until instructed later.
- 2). Coil the copper wire around the iron bar. While the loose 6-inch end hangs from the end of the bar, unspool more of the wire and coil it upward along the length of the bar. The wire should be coiled tightly, with each layer pushed snugly against the layer of wire below it. Once you've reached the top and completely wrapped the iron bar with wire (so that there are very few gaps between the wires where you can see the metal beneath it), let the wire hang off the top of the metal bar.
- 3). Wrap a thin layer of electrical tape around the first layer of wiring. This layer of tape should not be folded or kinked and instead form a flat, smooth surface over the layer of wire.
- 4). Use the remaining wire that is hanging off of the top of your metal bar to wrap a second layer of coil back down along the length of the bar. A second layer is optional but it will create a stronger magnet.
- 5). Cut your wire off the spool. Once you've finished the second layer of wire coil, let it hang 6 inches down past the end of the metal bar (this will hang directly next to your first 6-inch copper wire length from step 1). Cut it from the spool so that the metal bar is wrapped in two layers of wire, with two 6-inch lengths of wire hanging from the bottom.
- 6). Strip 1 to 2 inches of insulation off both ends of the copper wiring. Leave the copper intact underneath, making sure not to nick or cut it.
- 7). Tape one end of the copper wire to the negative terminal of the battery. Tape the other end of the wire to the positive terminal. Once you've attached both wires to the opposite terminals, the circuit is complete and your electromagnet should be functional. Hold it next to a metallic object such as a screw or nail to observe the attraction.
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