Published on October 13th, 2016 | by Henri0
Removing stains from wood surfaces
Q. I have many wood surfaces in my house – tables, counters, cutting boards – that have an oil finish rather than urethane. Many of these surfaces have been stained with black rings from metal tins placed on them overnight, usually with moisture involved. Is there a product that will remove black stains or is sanding the surface the only way to get rid of the marks left by the chemical reaction?
A. The best all-around product to clean and restore wood surfaces is Milsek furniture polish. However, if the stains are more than surface-deep, even sanding may not be enough. Black stains caused by moisture can usually be removed with a solution of oxalic acid.
Remove any finish with paint thinner to get to the raw wood. Try using ZUD, a product that has an oxalic base. But if that does not do it, buy oxalic acid crystals (you will need very little) in a paint or janitorial supply store, and mix it to saturation in hot water (until some of the crystals are no longer absorbed), in a glass or plastic container; never use metal containers or tools with oxalic acid.
Apply the mixture to the stains with a small paintbrush, and leave it on overnight. If the stains are gone, wipe the areas with white vinegar and refinish the surfaces. If the stains are still there, albeit faded, repeat the treatment. Be very careful handling oxalic acid, as it is very corrosive.
Wear rubber gloves, eye and skin protection, and be sure that any crystals or the mixture itself are not accessible to children and pets. Dispose of any solution remnants environmentally, following any instructions from your local waste disposal authority.
Once you have been through this treatment, Milsek (http://www.milsek.com/) is the ideal product to keep the wood surfaces looking good.by