If this fails, apply a paste of rust-removal jelly containing phosphoric acid (available at hardware stores as naval jelly) mixed with whiting.
Treat rusty metal with rust remover, such as naval jelly, which is available in hardware stores.
For example phosphoric acid in the form of naval jelly is often applied to ferrous tools or surfaces to remove rust.
If the stain is deep-seated, apply a thick coating of a rust remover like naval jelly and follow the manufacturer's instructions.
Prohibitions include wire wheels, naval jelly, chemical strippers and polishing.
Use a product such as naval jelly.
To remove rust or corrosion from iron, steel or aluminum that is not to be painted, use naval jelly, a compound with phosphoric acid.
For metal that will remain unpainted, apply rust remover, sometimes called naval jelly, instead of converter.
Before sharpening an edge or blade remove any rust by scrubbing the metal with steel wool or an emery cloth or by applying rust remover like naval jelly.
"We used naval jelly, WD-40 and good old elbow grease" to clean and separate them.