I used bolt cutters to cut a piece from one of those wire campaign poster sign legs, took that piece and wrapped it (all in the same direction) with wire that was unwrapped from a small fan motor, then hooked it up to a 9 volt battery. I chose that as the iron core because I read that bolts are hardened iron and aren't as good as "soft iron". I verified that magnets stick to it. The result is nothing, not even the slightest capability to move a paperclip (that does stick to magnets). Lick test tells me the battery is live. I'm sure the wire is coated because it was visible when I was burning the coating off the loose ends (and because of where I got it.) I know the circuit is complete because hooking a little bulb with it in series makes it light up.
1) The iron wire core I chose isn't suitable despite sticking to magnets readily.
2) The iron is too big/small to be affected by the too big/small copper wire wrapped too few times with a too weak power source. (But it should show at least a little magnetism, right?)
3) The wire shorts in such a way that it bypasses the part where it makes an electromagnet.
4) I've forgotten some fundamental detail about how this works.
Pictures below. How can I determine what went wrong and/or how can I make sure it works on my next attempt?
Left to right: Where I got the wire, the electromagnet I tried to make, another segment of wire, and the Lego brick its intended to fit in
A close up. The plastic pieces on the ends are just to hold it inside the brick. Its put together with super glue.