How to Clean Rust by Electrolysis
- 1). Locate several pieces of rebar that are least four inches taller than the plastic bucket you'll be using later. Use a metal grinder to clean off most of the rust from the rebar. Clean one end on each piece of rebar down to the bare metal. Mix five gallons of water with eight ounces of laundry soda in the plastic bucket. Ensure the laundry soda is thoroughly dissolved so that no solid pieces remain.
- 2). Place the sections of rebar inside the bucket against its edge with the clean ends facing up. Space the pieces of rebar evenly around the edge of the bucket. Clamp the pieces of rebar firmly to the edge of the bucket with small iron c-clamps. Connect a length of electrical cable to the clean end of each piece of rebar.
- 3). Tie one end of a small iron chain to the rusty part. Tie the other end to a fixed point above the bucket that's not in electrical contact with the sections of rebar. Suspend the rusty part under the solution of laundry soap so that it doesn't touch the bucket or any of the pieces of rebar.
- 4). Attach the battery charger's positive lead to the electrical cable that connects the pieces of rebar together. Attach the battery charger's negative lead to the rusty part.
- 5). Turn the charger on. Bubbles should form almost immediately on the pieces of rebar and the rusty part. The orange rust on the part should begin to turn black as it's reduced to elemental iron.
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