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I recently bought a 22 and 30 gauge loop of magnetic wire from radio-shack. The loops of wire were colored differently (if this makes any difference) and on the package it noted how these wires were good for creating electromagnets. I bought these with the purpose of creating a small generator. I ran 3V on the 30 and 22 gauge wires and to my surprise; there was no current flowing. I know there was no current because I used a multimeter to check this. Also, when I replaced the wire with another I had, current flowed normally. What's wrong with magnetic wires? Why isn't current flowing through them?

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There is a thin ("invisible") coating of insulator on this wire - this is actually what gives the wire its color (green, blue, red etc instead of "copper colored"). You can either scrape it off with the edge of a sharp knife, or burn it with a lighter etc. Until you do, it will appear not to conduct.

I happened to have a reel at home. According to the package the coating is "enamel" and there are instructions:

enter image description here

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    $\begingroup$ In a kit that included making the motor from scratch, the insturctions said to use steel wool on the ends to remove the varnish. $\endgroup$ – JDługosz Jan 26 '15 at 19:22
  • $\begingroup$ @floris So should all the coating be removed in order for the magnetic field to work correctly or should only the edges be peeled in order for it to conduct? $\endgroup$ – reddead Jan 26 '15 at 19:23
  • $\begingroup$ You just need to remove insulator where you intend to make electrical contact, and leave it intact elsewhere. That way when you make multiple windings, the current has to "go around the long way" instead of flowing across from one winding to the next (which it would do if you had no insulation at all). And the advice from @jdlugosz to use steel wool seems very sound. $\endgroup$ – Floris Jan 26 '15 at 19:25
  • $\begingroup$ The insulation is critical to its function. Very thin insulation makes it especially suited to the purpose. The original experimenters used paper! When you make your project, learn about how it works exactly. $\endgroup$ – JDługosz Jan 26 '15 at 19:35

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