Cast iron fence is attractive and durable. But as with all cast iron, it is exposed to rust when subjected to unprotected moisture. Never use a rust remover formulated fore cast iron on other materials, such as plastic or cement. Rust removal from cast iron fencing can be boring and thorough. You will find your bet more rewarding if you have completed one small fence part at a time. So you can see the results of hard work before proceeding to the next section.
To remove rust from a cast iron fence is starting with wipe the first part of the fence from where to remove rust. These with filler or shop towels. Donate your rubber gloves, mask and glasses. Spray acid-based rust remover on a clean dry cloth until the cloth is damp. Apply cloth to rusty stains on cast iron fence. Holds the cloth in place for about 30 seconds to allow the rust removal agent to penetrate the cast iron.
Rub firmly with the cloth to remove the surface. Move from rust stain to rust stain, remove surface rust. Some heavier rust can remain on the fence part. Spray a wire brush with rust remover. Scratch heavier rust spots with the brush. Wipe the rust residue of cast iron fence section with a clean, soft cloth. Remove rust that can be made in cracks, rolls and cracks. These using a non-steel abrasive sponge sprayed with rust remover. Work one area at a time; remove the rusty residue with a clean cloth as you advance along the fence section.