Woods That Contain High Amounts Of Tannic Acid

(such as white and red oak, cherry and walnut) can be ebonized by brushing on an acidic solution of iron and water. Depending on the species, the black color that results is likely to contain shades of brown, red or green. The coloring is usually uniform and consistent, without the blotching that sometimes occurs with oil-based wood stains. On oak and other woods that have large pores, the effect is particularly striking because the pores usually remain light in color.

The technique

In a glass container, immerse a pad of steel wool (steel is mostly iron) in white vinegar from the grocery store. Screw on the lid and allow the steel wool and vinegar to react for at least a day. Shake the solution occasionally.

Finish-sand the piece you want to treat to 180 grit. The iron and vinegar solution contains lots of water, so it's a good idea to preemptively raise the grain. Dampen the sanded piece with water, let it dry and then sand lightly with 180 grit to remove the raised fibers.

Apply the solution with a cloth. There's no need to saturate the wood; a good dampening of the surface will

Bleached Finish j

Sodium Hydroxide Wood Bleach

BLEACHING OFTEN MAKES WOOD LOOK LIFELESS, but I

find its effect on walnut to be striking. I bleach walnut until it's nearly white and then lightly sand the surface to bring back the ghost of the original color.

The technique

Two-part wood bleach from the paint or hardware store works the best. The two components are hydrogen peroxide and sodium hydroxide (lye), so be careful. Wear rubber gloves and eye protection and strictly follow the instructions.

Finish-sand the piece you want to bleach to 180 grit Bleaching solutions contain lots of water, so it's a good idea to preemptively raise the grain. Dampen the sanded piece with water, let it dry and then sand lightly with 180 grit to remove the raised fibers.

Don your protective gear and follow the manufacturer's directions to apply the bleach. Some tell you to apply Part A, wait a few minutes, and then apply Part B; others tell you to mix the two parts together and apply the mixture. Wipe on a light coat of the solution (Photo 1). There's no need to saturate the wood; just dampen the surface. Let the piece dry. Then repeat the process—it usually takes seven or eight applications to bleach walnut white. When you're satisfied with the white color, wipe the piece with a damp cloth to remove any bleach residue. Then let it dry.

Sand lightly with 320 to 400 grit to gently ghost back the walnut color (Photo 2). Then apply lacquer, wax or a clear water-based finish to preserve the bleached look.

Sand lightly to ghost back the walnut color. Then apply lacquer, wax or a clear water-based finish.

Remove the wood's natural color with two-part wood bleach. Several applications may be necessary.

Wood Tannin

do. On tannin-rich woods, the reaction can be instantaneous (Photo at right). Let the piece dry and then repeat the process. If the surface starts to feel rough, lightly sand between applications. Eventually the color will become uniformly dark; you can stop whenever you like, though. Sometimes a lighter shade of black looks great, so you may want to call it quits after one or two applications. When you're satisfied with the color, wipe down the wood with a damp cloth to remove any residue from the solution. Let the wood dry before applying a finish. Oil finishes, wiping varnishes and oil/varnish finishes enhance this coloring process.

Wiping a solution created by immersing steel wool in household vinegar onto woods that contain high amounts of tannic acid causes a chemical reaction that turns the wood black.

Charred Finish

Torch Method Wood FinishTorch Method Wood Finish
Lightly scorch the wood with a torch. Move the flame continuously and quickly so the wood doesn't overheat.

EBONIZED WOOD OFTEN ISN'T PURE BLACK. Depending on the method used, the color usually includes shades of brown, red, purple or blue. A rich, deep, pure black is hard to achieve—unless you char the wood with a torch. This method works on any wood, although the results will look distinctively different from one species to another, depending on the character of the wood. Also, a uniform appearance is easier to achieve on face and edge grain than on end grain.

This finish is tricky because it's fairly easy to overheat the wood and cause it to crack or ignite. End grain surfaces and thin pieces (less than 3/8" thick) are especially vulnerable. It's a good idea to develop your charring technique by practicing on pieces that aren't "keepers."

The technique

Finish-sand the piece you intend to char the same as for a clear finish—charring doesn't cover sanding marks or torn grain as well as you might think. Work in an area free of combustible materials. Wear a heavy protective glove to hold the piece while charring its surface, and use a propane torch with an adjustable flame so you can control the heat level.

The best approach is to char the wood to a uniform appearance in stages, stopping to brush off the burned debris between applications of heat. Start by lightly skimming the wood's surface with the flame (Photo 1). Make slightly overlapping passes and move the torch continuously. If the wood ignites, simply blow out the flame and let the wood cool before resuming.

After lightly charring the entire surface, let the piece cool, and then go over it with a soft metal brush to remove the ash and other completely burned debris (Photo 2). Brushing often accentuates the latewood, which is usually harder and more resistant to the flame than the earlywood. Torch and brush the entire surface a second time to make the charred color as uniform as possible.

The last step really brings out the rich, carbon-black color. After the piece has cooled, apply a coat of oil finish. I usually use boiled linseed oil or pure tung oil (both thinned by one-third with mineral spirits). Rags soaked with boiled linseed oil are flammable, so dispose of them properly.

Brush off the loose debris with a soft bristle brush. Repeat the process, if necessary, to create a consistent black color. Then apply an oil finish to intensify the black.

Blended Finish

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Responses

  • Bowman Greenhand
    What wood species contain tannic acid?
    5 years ago
  • Diamond
    Is there tannic acid in cherry wood?
    5 years ago
  • Elias
    Which woods contain tainic acid?
    4 years ago
  • letizia
    Can uou paint over tannic acid wood?
    3 years ago
  • cameron
    Does poplar wood contain tannic acid?
    3 years ago
  • Semolina
    What woods are high in tannins?
    2 years ago
  • adele
    Does cherry wood have a high tannin level?
    1 year ago
  • Salla Tiainen
    Does popular wood have high tannin levels?
    1 year ago
  • amedeo
    How long kamari wood contain tannin?
    1 year ago
  • gundolpho
    Does sekelbos contains tannin?
    1 year ago
  • madoc
    Does mesquite wood contain tannin?
    1 year ago
  • awet yusef
    Is there tannin in white ash?
    11 months ago
  • sarah
    Is ash a tannan rich wood?
    9 months ago
  • franco cattaneo
    What species of wood has the most tannin?
    9 months ago
  • Aapo Rasi
    Which wood has tannins?
    9 months ago
  • Mamie
    Does have sake have tannins?
    6 months ago
  • kerttu
    Does bees wax have tannins?
    6 months ago
  • Ariam
    Does seasoned oak have a high tanic acid level?
    6 months ago
  • petri
    Does tannin react with acid?
    4 months ago
  • BASSO
    Is poplar a low tannin wood?
    3 months ago
  • Imelda
    How to make tannic acid from wood?
    3 months ago
  • bob
    Is walnut an acidic wood?
    2 months ago
  • melilot
    What wood has highest tannin content?
    16 hours ago

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