Vinegar works as a wood stain when you add a metal object in the mix and let it sit in a glass container for a week. A handful of pennies will produce a beautiful pale Caribbean blue stain. A wad of steel wool will give you a rich reddish hue. A combination of tea and a metal object in vinegar will produce a black stain. Log this away for later.
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All-purpose cleaners won't remove rust stains from sinks, tubs and toilets, even with a lot of elbow grease. The trick is to use a stain remover like Super Iron Out ($10 for a 5-lb. jug). For toilets, add Super Iron Out to the water in the bowl, then clean with a stiff nylon-bristled brush.
A lemon works to remove tough food stains