I know what I'm about to say sounds heinous, but you can use sandpaper to remove the heavy rust spots. FINE 600 GRIT paper with some olive oil. It sounds terrible, but it really works and does not damage the blade. The finest grit feels almost like a normal piece of paper, but it has just enough resistance to remove flaky rust. I would also recommend the pineapple juice soak, works wonders. Don't ever even contemplate naval jelly!!! Only good for cleaning old tools and such as it pickles the metal odd colors (Long ago, been there, done that...

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