Cast Iron Finishes
Bare Iron: Cast iron does not have a protective coating - so exposure to even moist air can cause rust. To remove rust before painting - Use white vinegar. The vinegar reacts with the rust to dissolve it off of the metal. To use, soak the metal in white vinegar for a few hours and then scrub the rusty paste off. If the object is too big to soak directly in the white vinegar, pour a layer over the top and allow it time to set. You can also wipe it down with a rag soaked in vinegar.Be creative when finishing your cast iron décor.
You might want to try hand painting it.
Or try rusting it and then applying a coat of paint for a distressed finish.
Try dipping aluminum foil in the vinegar and using it as a brush to scrub off the rust. It is less abrasive than steel wool, but will still do the trick in removing the rust. You can use regular vinegar and simply allow your rusty metal objects to soak in it for up to 24 hours before rinsing. This method should not require as much scrubbing.
Paint Finish: Cast iron brackets can be painted with any type spray paint that is designed for metal. If you plan on using the piece outside you may want to get a paint that has a rust inhibitor in it.
Rust Finish: Your cast iron bracket will rust beautifully by just leaving it outside in the rain for a couple of days. If the rain is not cooperating you can water the pieces a few times a day. This will take a little longer but achieve the same results.
Once your bracket has rusted you need to clean it and brush it off with a scrub brush to remove any loose oxidation.
The last step is to seal the iron. You can do this using any clear polyurethane spray paint. We have achieved good results with Minwax clear satin finish polyurethane spray.