Just an afterthought on the subject, OP has already conceded to scrapping them. The older ballasts contain an oil that contains PCBs. PCBs are on the EPA's hit list. Given the opportunity, I would spread the oil up and down the main highway through town (US-11) just to stir things up a little. I am so old that any contact with PCBs doesn't scare me. Along side a plethore of other chemicals that are as or more dangerous. And the nuclear test source I used to carry in my pocket as I went up the cupola. . .
The actual thought here is that "magnetic" ballasts, the non-electronic type, contain a goodly supply of small, enameled wire. The enamel will crack as it is unwound, but it is still good copper. It will be easier to recover than the windings from a dead fan motor. And a damn sight cheaper than spooled, new wire of the same size. Anyone interested in winding solenoids (or Tesla coils) should look into the recovery.
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