Removing Dark Rings From Wood Furniture With Oxalic Acid
- 1). Pour 1 pint of hot water into a jar safe for microwave use. Add 2 to 4 teaspoons of oxalic acid crystals to the water and stir with a spoon. You must keep the oxalic acid mixture warm at all times during the following process. Reheat the mixture in a microwave oven if necessary, heating on "high" at 30-second intervals.
- 2). Dip the bristles of a clean paintbrush in the warm mixture and brush the mixture directly on the dark rings. Let the oxalic acid mixture dry on the rings.
- 3). Repeat the previous two steps until the dark rings are no longer visible.
- 4). Dissolve 2 tablespoons of borax in 1 pint of lukewarm water. Mix the powder and water with a spoon. Wipe the wood furniture with a cloth dampened in the mixture. The borax will neutralize the oxalic acid and stop the bleaching process.
- 5). Wipe the borax residue off the wood furniture with a damp cloth and dry with a soft towel.
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