Step 4: Put The Core Back In
For this to work as an electromagnet we will only use the "E" core pieces.
To reassemble the core, the easiest way to put it back together is to put all but a few pieces in at once. Then put the rest in on at a time, and pound them in with a hammer.
The core should stay in from friction alone, but you could use more varnish or super glue to hold them together.