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Bleaching in Furniture Restoration

wood finishing

by Alan Noel
Professional Wood Finisher



Bleaching is a tool that is used sparingly when restoring an old piece of furniture. Often there will be iron stains from old nails, black or very dark water stains or sun bleached areas that are far lighter than the surrounding areas, caused by an object being in the same location for a long period of time. Other cases where bleaching may be used include trying to deal with a mistake such as using the wrong color stain to begin with or inconsistent coloration of the lumber being used in a project. That being said, the options for bleaching are few. The options are: oxalic acid, chlorine bleach and a two part bleach, otherwise known as A-B bleach. Here are some tips on the different types and how to use them.

  1. Oxalic acid is used for fading iron and water stains from the surface and is quite effective. In a glass jar, mix the acid crystals into hot water by stirring in the crystals slowly until they begin to gather on the bottom. This is a saturated mixture and ready for use. Wearing rubber gloves, eye protection and a respirator, completely cover the entire surface to be bleached with the mixture. Spot bleaching is not recommended. The results can be seen after the bleach has dried. The oxalic acid will appear in crystal form on the surface and has to be neutralized with clean water until no crystals reappear after drying. Be sure to sand bleached areas in good ventilation and to wear eye protection and a respirator. Repeat as necessary.
  2. Chlorine or household bleach is used to lighten most dye stains. For a more effective chlorine bleach purchase some calcium hypochlorite from a pool supplier and mix the same as oxalic acid. With proper safety in mind, apply to the entire surface and let dry. Repeat if necessary. Again, spot beaching is not recommended and be sure to wash with clean water and let dry.
  3. Two part or A-B bleach is comprised of sodium hydroxide and hydrogen peroxide and is most effective at removing the natural coloration of woods. Two part bleach will help to eliminate some pigmented stains but isn't very effective on dye stains. Some say to apply Part A first and then apply Part B or mix them both before application. I personally can't see any difference in the results either way.
  4. As with all bleaches, safety comes first and be sure to rinse well with water. Distilled water is best.



Visiting Atlanta? Attend one of Alan's upcoming highly informative Highland Woodworking wood finishing seminars:


Gilding & Gold Leafing, August 10, 2011

Antiques Show and Tell, August 13, 2011

French Polish Workshop, September 7, 2011

Antiques Show and Tell, September 10, 2011

Antique Restoration, September 17 & 18, 2011

Spray Finishing, September 24, 2011

Coloring Wood, September 28, 2011

Visit Highland Woodworking's Online
Wood Finishing Supplies Department




Alan can be reached directly via email c/o Alan Noel Furniture Refinishing at anoelfurniturere@bellsouth.net.


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