Bleaching wood

Choosing the correct bleaching agent makes all the difference when altering the natural color of wood to achieve uniformity. 1998.

by Rick Hill

Q.
I have two cubes of birdeye maple. I used household bleach to whiten the tops, but they did not lighten so I used oxalic acid. This turned the tops light gray. Do you have any suggestions?

A.
Your dilemma started when you used the wrong bleach for your lightening. Many people make the mistake of thinking "bleach" in woodworking terms is the same bleach we see in household use.

Bob Flexner, in the book "Understanding Wood Finishing" (from Rodale Press), does an excellent job of explaining the different types of bleach and their individual uses. Flexner states "There are three types of bleach used in woodworking...Two-Part bleach (sodium hydroxide and hydrogen peroxide) removes the natural color from the wood. Chlorine bleach removes the dye from wood....And Oxalic Acid removes rust and water stains from wood."

Your problem is now the gray in the bleached maple. Your best bet is to now use the right system--the two part bleach. It may remove the gray. Then go on as before. If the gray does not come out you can try to stain the wood to add color, but take into consideration that the gray will be the undertone and will affect the color.

Rick Hill is an independent representative and consultant for industrial wood finishes. He has been involved in the woodworking industry for 12 years, and has been known to actually hold, shoot, and clean a spray gun.

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