Remove melted plastic from metal by either cooling the plastic down to make it brittle enough to break off, or by heating the plastic to make it pliable so that it can be scraped off. It is also a good idea to use WD-40, nail polish remover, rubbing alcohol or, for extreme cases, fine steel wool or fine-toothed sandpaper to buff out the area once the plastic is removed.
Melted plastic should not be burned off because this releases toxic fumes. If the plastic is melted onto an oven rack or other small- to medium-sized metal object, simply place the metal in the freezer until the plastic becomes brittle. A razor blade or a hammer can then be used to scrape or carefully break the plastic off. Another effective method for removing melted plastic from metal is to use a hair dryer to heat up the plastic before attempting to scrape it off using a razor blade. If the metal in question is the heating plate of a clothing iron, then remove the plastic by running the iron over a section of aluminum foil that has salt sprinkled on it. The salt will help loosen the plastic from the metal and make it easier to remove.