Removing rust stains
Rust stains come from iron in the water supply, which can only be permanently removethrough installation of an iron filter. Occasionally iron is dissolved from rusting waterpipes or mains by corrosive water. Iron stains can be removed by a weak acid solution,usually oxalic acid which is highly toxic and must be handled with care. Never usechlorine bleach as this sets the iron stain.
Fresh iron stains on plumbing fixtures such as sinks, bathtubs and chrome willgenerally yield to treatment with heavy duty cleaning compounds containing largeproportions of trisodium phosphate. Apply cleaner with damp cloth, pad or sponge. Rubdiscolored surface until stain is removed. Rinse. Wipe dry and polish.
Heavy, stubborn rust stains can often be removed by oxalic acid stain remover compoundssuch as Zud or a tri- chloro-melanine compound such as Barkeepers Friend. Followdirections carefully.
For rust stains already set on bathroom or kitchen plumbing fixtures, dissolve oxalicacid crystals in hot water and add enough whiting or talc to make a soft paste. Apply thispoultice to stain and let dry before removing. Rinse and polish.
Use with care: It is poisonous.
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