Vinegar has already been mentioned for scale removal, and that is my
preferred way to remove scale. I buy it in large lots. The best way to
remove rust is by the electrolytic method. Fill a 5 gallon plastic bucket
with water, dump in one tablespoon full of laundry soda per gallon of water,
and hook the negative (-) lead of a battery charger to the item you wish to
derust, and the positive lead to a large piece of stainless steel or regular
steel that you will submerge in the water near the item. Plug in the charger
and check the current to be sure it is not drawing too much. If it is,
simply separate the anode and cathode a little to reduce the current flow.
Leave it a couple hours for thin rust, and perhaps 12 hours for thick rust.
Remove the item and use a scowering pad to easily clean all the rust and
junk off the item under a stream of warm water. Dry it well, and immediately
coat with WD-40, or oil. It is chemically clean and will rust almost
instantly once it is out of the tank. I used this process on all of the
parts of my power hammer, except the main frame, when I was restoring it. It
is a superb method to remove 100% of the rust, even down in the pits if
heavily rusted, and it is labor free. You can't hurt the item by leaving it
in the tank too long either.
Golden Age Forge
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