Well, I busted into one of these tonight, and WHOOOOHOOOO!!!!
I remembered reading this thread, and wasn't very optimistic. I cut into a bit with a pocketknife and saw heavy gauge copper wire, so I decided to dig in. Out of disks for my angle grinder, so I busted out the twinblade saw. After a few trial and error attempts, I just cut as close to the inner core as I could, then pulled the loose in through the center from the other side. After I got through one layer, there was a layer of thin tape-like wrap, and then ANOTHER layer.
Read it and weep, folks.....
Approx. 30lbs of Cu and the core weighs 45lbs.
About an $80 payday for an hour of fairly easy work.
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