im a new scrapper and need help

At the weld up against the copper spool set an ax. Use a short armed sledge hammer to whack the ax. A few good whacks and the one side of the transformer will come apart and you can get the copper spool out.

If you do it this way, wear good eye protection as your likely to have a steel chip come flying off one of those tools like shrapnel. Their not made to smack together, their both a hi-grade steel. You could use a hammer and chisel.