I have been reading on the net about cleaning a rusty knife, some stuff i found says use and onion, a potatoe and vinegar.

Does anyone have any tricks they have used before to bring back a blade and protect it?

I just recently read somewhere you can use 1/4 baking soda and peroxide to a paste like consistency will take rust and cooking discolor off pans. It might work for your knife too. Worth a try and most of us have that stuff already at home.

Coke does a good job of eating rust. You can also scrub a lot off with Barkeeper's Friend.

If it's really rusty though it's going to be pitted which would have to be buffed/ground out.

-spence

was watching a show on refinishing gun barrels that rusted
and they used a very light oil and fine steel wool for starters.

If you have fine rust spots on the blade a #2 pencil will rub the rust right off. The graphite will chip away at the rust until its nice and smooth again. What you get back is going to depend on 1. The quality of the blade to begin with. (I'm thinking low as its apparently rusted) and 2. How much time you are willing to work at getting it cleaned up.
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Steel wool or a scotch brite pad will work.
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