How Grain Accepts Stain

Summer-growth wood has narrower channels.

Some woods tike stains unevenly. Large spring-growth pores of red oak (top) stain darker because they hold aor than the summer-growth pores. Spring-growth wood of white pine is Kghter in color than summer growth but stains darker because larger pores absorb more pigment (bottom).

up with pigment all along the exposed length. But, except for the large, spring-growth channels on Douglas fir, oak and ash, these channels aren't wide enough to hold much pigment.

When the channels are sliced across their length, they'll hold quite a lot of pigment. The pigment penetrates the open end of the channel and stops only when the air in the channel prevents further penetration, or when the opening of the channel is sealed over.

This explains why stained end grain appears so much darker than side grain: more pigment has penetrated into the open end-grain pores. And this is why you get splotchiness on boards that have a swirly grain pattern. The more the channels swirl to the perpendicular, showing up on the surface as pores, the more pigment they accept. — B.F.

dust and apply the next coat.

The second problem with water-based stains is that the pigment doesn't penetrate into the pores and scratches as fast as solvent stains do. Solvent takes the pigment into the wood almost instantly, so you can wipe almost instantly (in spite of what some instructions tell you). Writh water you need to wait a minute or two before wiping off the excess or the result will be an uneven, splotchy stain penetration.

The third problem is that water, and the acrylic resins, dry relatively fast, so you have to work quickly to cover the entire surface and get the stain wiped off before it dries. Otherwise you'll have streaking.

Water-based stains are a relatively new technology, but they're becoming more and more common. Chemists are busy improving the working qualities, so look for continuous improvement in the performance characteristics of these stains.

Cures for Common Staining Problems

The most common staining problems are streaking and splotchiness.

Streaking —Streaking occurs when excess stain dries unevenly on the surface of the wood. Streaks won't occur if you wipe off all the excess stain, but they're difficult to avoid in situations where vou want to build up a coat of stain on the surface to obscure the wood. When this is your goal, spraying is the best application method for avoiding streaks. Spray on just the right amount of stain so you don't have to wipe anything off. If spraying isn't an option and you have to use a brush, sponge or cloth to apply a heavy coat, minimize streaking by gently smoothing out the excess stain in the direction of the grain.

Splotchiness —Splotchiness can be caused by uneven grain or by unevenly-sealed wood. Uneven grain is common and natural, and I usually accept the wood for what it is rather than try to change it. But if you can't live with the effect of stain on uneven grain, you can usually even out the pigment penetration by applying a highly-thinned coat of finish, called a "wash coat," before you apply the stain. The wash coat partially fills the pores of the offending grain but, due to the high percentage of evaporating solvents, not enough finish gets into the pores to stop them up completely. It only reduces the room for pigment penetration. Since a wash coat reduces the space for pigment everywhere, there is less darkening of the wood.

Traditionally, shellac thinned with five to ten parts denatured alcohol was used for a wash coat. Now there are ready-made "wood conditioners" and "pre-stains," such as Minwax Wood Conditioner, designed for this purpose. These conditioners are usually highly-thinned linseed oil or varnish.

Uneven sealing can be caused by glue that has seeped out of the joints or been deposited on the surface bv your fingers, or by traces of old finish you missed when you stripped an old piece of furniture.

Once you've applied the stain, it's difficult to repair these splotchy spots. The best way to handle splotches is to be conscious of them from the beginning: try to avoid creating them. Practice cleanliness in gluing up, and check for shiny spots on a stripped piece (which would indicate that all the finish is not off).

If you have to repair a splotchy spot, the best way I've found to remove spots of glue or unstripped finish is to scrape the spot off with a sharp hand scraper. Then I carefully sand the clean wood with same grit sandpaper I used for the initial finish sanding, being careful to avoid sanding the stained area as much as possible. Then I reapply the stain to the sanded area and wipe off all the excess.

Sometimes you can blend repaired spots into the surrounding area by sanding the spot and the wood all around the spot while it is wet with stain. That may get the color match close enough.

If you can't seem to get the glue-splotched areas to blend in, you might be able to remove enough of the pigment with the appropriate solvent —mineral spirits, lacquer thinner, or water—if you can catch the problem before the binder has fully cured and then restain. If not, you'll have to strip the entire piece with paint-and-varnish remover and start over.

Staining wood is usually quite simple, and the rewards considerable. Most of the problems that occur are caused by a lack of understanding of how various stains work and how they differ from each other. Rather than just buying the first stain you come across, give a little thought to choosing the type of stain that will give you the working qualities and results you want. A

Bob Flexner restores furniture at The 14brkbench in Norman, Oklahoma. He wrote about shellac and varnish in the Nov./Dec. 1989 AW and alxnit aniline dyes in the Now/Dec. 1988 AW.


Jewelry Box

I enjoy making jewelry boxes. They're ideal for putting small but precious bits of wood to good use. and they make great gifts. They also provide the perfect opportunity for honing your woodworking skills with a minimum of risk in materials.

When making a jewelry box, you need to take into account the types of jewelry that the box will hold. Most of the people I've made boxes for have wanted a place to store necklaces, brooches, and earrings. On rare occasions, I've been asked to add a special provision for rings, but I've found most people don't change rings like they do other pieces of jewelry.

I've made jewelry boxes of all kinds, but the one you see here is my most popular version. It includes a lower section, with compartments for necklaces and brooches, and an upper sliding tray with smaller compartments for earrings and rings. The box sides are dovetailed and the lid is a partially recessed frame-and-panel.

In this article, I'll describe how to make this box, with some tips on how you can modify my design to suit your needs. (For more on boxmaking, see May/ June 1990 41V.) The methods and design I'll describe are a mixture of my own and those I learned from James Krenov and the staff at the College of the Redwoods in Fort Bragg, California.

Building the Box

When choosing the wood for the box, I try to find an exciting piece for the top panel—a piece with a lot of figure, spalting, or colors—and then surround it with a box and frame of a complementary, straight-grained wood, quieter in nature. In this way the panel in the box is like a gem in a setting, in keeping with the precious objects inside the box. I've found some of my best panels hiding in a piece of firewood or in wood I've picked up on the beach.

Start by dimensioning the four sides of the box. For

Once yoe've routed the grooves for the bottom panel, file off the "fuzz" from the edges of the groove. Note that the groove on the tafl pieces stops short of the end.

a box of this size. Vie in. is the minimum thickness for the sides. This thickness is sturdy without being bulky; it permits well proportioned dovetails, while still allowing enough thickness for the hinges and the bottom panel grooves (see photo below).

To get a harmonious grain pattern around the box sides, I recommend you resaw the sides from a single board. Resawing allows you to construct a box so the grain pattern is continuous, wrapping around all four sides. If you're scratching your head, take a look at Fig. 4 to see how it's done.

I recommend resawing the box parts '/lo-in. thicker than the finished thickness to allow room for re-flattening the parts if they twist a bit while releasing their internal stresses. Leave the wood alone for half a day to let it reckon with these stresses. It's a good idea to resaw the other parts of the box and a few extra pieces (for use as joinery test pieces) at this time.

Once the resawn box sides have had time to mellow out, flatten them on the jointer, then thickness them to a fat '/jj-in. more than the final thickness. Ewnly handplane or scrape the inside surfaces of the box to remove the machine marks (leave surfacing the outside of the box until later).

Rip the box sides down to their 3'/2-in. width and true up the ends of the pieces. Cut them in. longer than their finished lengths for front, back, and sides. Be very certain here that the ends are square, or the box will be twisted. A shooting board works well for this.

The dovetails add a nice touch to this box. I won't explain how to cut dovetails, but if you're going at it for the first time and you need a bit of guidance. I recommend James Krenov's book The Fine Art of Cabinetmaking (1977, Van Nostrand Reinhold Company. 135 W. 50th St., New York. NY 10020) which has an excellent description of how to go about making beautiful, handcut dovetails.

Krenov taught me to lay out dovetails so that the outer tails are smaller than the central tails. This

Raise the bottom panel of the box to beef up the thickness of the panel and make the underside of the boat look as fine as the top.


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