I just got done bringing a hatchet & Hawk head back to life. Both were rusted and scaled, but not as bad as Your find. I used a new product called Evapo-rust (picked it up a Harbor Freight). Pretty cool stuff - Non toxic, biodegradable, PH neutral and water soluble. You soak the part for 1 - 12 hours, then rinse with water. I then went over the heads with a wire wheel in a drill after hosing them down with WD40. They both turned out pretty darn good, the stuff (Evapo-rust) works as advertised (even smells good). Good luck - Bob.
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