I seen a Lincoln stick welder on Ebay that looked to be about 50 years old. Owner says it had a heavu copper coil inside. I wouldn't doubt it. Somehow I just couldn't trust myself welding with something that old.
Hey if its free then grab it, dont quibble. Find out later if its any good for you. If your the honest type then you can always pass it back on through Freecycle, if its not for you.