Popular Woodworking 2000-12 № 119, страница 15
dremel Flexner on Finishing continued from page 24 A green toner was applied to the right side of this mahogany to "kill" the red and turn it brown. Toners can be used to adjust color after the application of a stain. then wipe off the excess before it dries. This will produce an even coloring as long as the wood isn't naturally blotchy and you have prepared it well. Other ways to apply color include the following. • Spray on a stain and leave it (called "toning" or "shading"). You can spray an entire surface to produce an even coloring, or you can limit the spray to parts (for example, just sapwood) to correct an uneven coloring in the wood or create special effects. You should thin the stain with four-or-more parts thinner to prevent lap marks. You can also tone or shade using a brush, but it's difficult to keep the coloring even. • Partially seal or "washcoat" the wood before applying a stain. A washcoat is any finish, sealer or white glue that is thinned to approximately 3 to 7 percent solids so it seals the wood just enough to prevent deep stain penetration and the resulting blotching on some woods. Most finishes are 20 percent to 35 percent solids right out of the can, so thinning the finish 5-1 usually gets you in the ballpark. When staining large or multiple objects, using a fast-drying, sprayed-on wash-coat followed by a liquid stain is more efficient than using a gel stain, but experimentation and practice are necessary to learn the right amount of washcoat to apply. A gel stain is far more predictable. Slow-drying washcoats, called "stain controllers" or "wood conditioners" are de- A full-strength stain was applied to the left side of this oak.The same stain thinned half with paint thinner was applied to the right side.The ratio of colorant (pigment and dye) to liquid (thinner and binder) determines how dark the wood will be. signed for wipe and brush application, but they also take experience to use successfully. • Seal the wood with a sanding sealer or first coat of finish and apply a glaze to create a special effect. (See Popular Woodworking, April, 2000, page 76.) A glaze is a pigmented stain thickened enough so it stays where you put it. You can use rags, brushes or specialized glazing tools to manipulate the glaze. Once you have the look you want, let the glaze dry, then coat over it to protect it from being scratched or rubbed off. • Seal the wood with a sanding sealer or first coat of finish and spray on a toner or shading stain to change the color of the wood or highlight parts of it. Toners and shading stains (the terms are often used interchangeably) are very useful for tweaking a color to an exact match. Remember that a pigmented toner obscures wood while a dye toner doesn't, and that over a sealed surface, toners and shading stains add color but don't bring out the wood's figure. Conclusion Every color-matching situation is different, and many are very challenging. Once you've determined the degree the wood will allow you to be successful, achieving a good match involves choosing types of stains and methods of application in addition to choosing the right color. PW Bob Flexner is a nationally known finishing expert in Norman, Oklahoma, and the author of "Understanding Wood Finishing." Circle #124 on Resource Directory Coupon 26 Popular Woodworking December 1000 |
