Bleaches In Wood Finishing: The Good And The Bad

by : Megan Cherry

Another way to change the color of your wood besides staining it is to bleach it. As you can imagine, stains add color, while bleaches take color away. In fact, it can take all of the color away so that the wood appears to have no color. If you choose to bleach your woodworking project, read on for a few basic finishing techniques that can save you a lot of headaches.

When you finish a wood, you can use bleach for many things. A bleach can lighten a wood's natural color or even remove it altogether. A bleach can also remove some stains from the wood, either intentional or accidental. In fact, they can be very useful because they can fix minor problems before they become major ones. There are three basic types of bleach to choose from, and you'll need to know which one to use for each situation, because each of these is pretty specific and not all will work in every situation.

The first kind, alkali peroxide bleaches, are usually sold in paint stores as a two-part liquid known as A/B bleaches. This type of bleach is usually used to remove wood's natural color. It will leave the wood with a very natural looking, even, off-white color base. This, in turn, can produce highly desirable results, depending on the finish you use. You can use these bleaches also to narrow the color differences between two very different types of wood so that they appear to match more closely.

The next type of bleach you can use in your woodworking project is chlorine bleach. This is very useful to remove dye stains or other stains that have occurred, such as coffee spills or grape juice spills on bare wood. As you probably know, chlorine bleach is used in laundry detergent applications and for swimming pools. Any laundry bleach will work, because it's concentration is actually quite weak. You might need to apply it several times to get the desired effect and remove the stain completely. You might also want to use chlorine bleach specifically formulated for pools. This is also known as "pool chlorine."

A third main type of bleach is oxalic acid. This is great because it's very selective in the colors it removes. For example, it does an excellent job at cleaning up iron-based stains, such as those that occur around nail holes. It also does a very good job removing dark water stains and other stains, but does not alter the natural color of the wood itself. Oxalic acid is usually found as a dry powder. It can then be mixed with water and applied to wood.

After you have bleached your wood, you need to neutralize the bleach when the cleansing or color removal is complete. There are different neutralizing processes depending on the type of bleach you've used. For example, with an alkali peroxide bleach, you'll want to rinse with water and then white vinegar. You need one part vinegar to two parts water. For chlorine bleach, rinse with two to three applications of distilled water. If you've used oxalic acid, use two to three applications of distilled water and then a solution of baking soda and hot water. The baking soda solution should be comprised of two tablespoon baking soda to one half pint of hot water.