I noticed recently that Paul Eric Rich bought a steering column that looked like it was a bit rusty. Don't know if it's been covered here before but there's an easy cure for that. Electrolytic rust removal. Mix about 1/2 cup of washing soda ( not baking soda ) to 5 gal of water. For small parts you can do this in a plastic garbage can or plastic pail. Larger pieces can be done with the limit only being the size of your container. I use rebar as the sacrificial anode. Attach the POSITIVE charge to the rebar and the NEGATIVE charge to the rusty part. Submerge both in the solution, keeping them separated. I turn the battery charger on to 10 amps and watch the fun. Somewhere less than 48 hours will take off even the most stubborn rust. The inside of a tube can be done easily too. Insert the rebar into the tube using isolators to keep the bar from contacting the part. I've done this on aircraft lift struts 14' long. The solution is environmentally friendly too. Throw the left over solution right on the lawn if you want to.
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