http://www.lanternnet.com/faqs.htm
My method varies a little from theirs but overall it is similar. Here is what I do: Take a 12 oz. bottle of Grandma's or Brer Rabbit sulphurated blaskstrap molasses and dump the contents in a 3-5 gallon covered bucket. (I use one of the red & yellow cat sand bucks with snap-top lid.). It's best to start with hot water as it aids the distribution of the molasses evenly though the water, stir in until the water is an even color. Dunk the bottle in too and rinse out all the dregs after you dumped the molasses out. Then put the item to be derusted in the solution. Let it sit for 24 hours then take the item out and scrub it with a stainless-steel wire brush. I buy the Lincoln welding brushes at Home Depot as they are 4x the size of the Harbor Freight toothbrushes and they retain their bristles a lot longer. Scrubbing loosens the rust top layer and exposes what's underneath it to the action of the solution.
Put the item back in the solution and let it soak some more. The longer it soaks the better it works although you will likely need to scrub the item a few more times before you've removed all the rust. Once it is derusted to your satisfaction, rinse the item thoroughly in fresh water, dry immediately, then lightly oil. The molasses solution will loosen some paints but is fine on plating. I am not sure about plastic but have a knife with plastic scales soaking in it right now and will update after it is done. The best thing is that it does not do any harm to solid metal, it only goes after rust and grease/oil too. The downside is the stuff reeks after a few days if uncovered. It will also develop a foamy scum on the top that you can skim off with a paper towel. Eventually some mold will form too but that can be skimmed off as well. I usually dump it after a month. You can make much smaller amounts than 3-5 gallons worth. I make the big dose because I fill the bucket up with many items and process them en masse. It works spectacularly on cast iron pans, they come out looking new.


