Popular Woodworking 2009-04 № 175, страница 55

Popular Woodworking 2009-04 № 175, страница 55

Coarse-grained woods. Common coarsegrained woods include from the top: plainsawn oak, quartersawn oak and ash. All stains and finishes look good on these woods.

mahogany has been used so extensively for so lor.g, it makes more sense to classify it as a medium-grained wood along with walnut, hickory and pecan.

With the exception of teak and rosewood, exotic woods were rarely used until recently, and then usuallyjust for decoration and veneer. Now a wide variety of exotic woods are used for bowl turning, decks and furniture.

Most ol these woods are medium-grained, but many are very distinctive in color and figure and therefore fairly easy to identify once you have become familiar with them. 1 don't have any easy categories that will help.

Finishing the Five Categories

Here are some thoughts about finishingeach of the five categories of wood.

Pine and related softwoods have a very pronounced grain - soft, absorbent, white spring growth alternating with hard, dense, orange sum mer growth. The spri ng growt h absorbs stain well, but the summer growth doesn't. So staining these woods usually reverses the color, making the spring growth darker than the summer growth.

Pine also tends to blotch, which can be quite unattractive.

On the other hand, pine finishes well with any finish, though I don't like oil finishes because so many coats are usually required

Flexner on Finishing

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Medium-grained woods. Three common examples of medium-grained woods used in woodworking are from the top: mahogany, walnut and butternut. These woods are widely considered the most elegant when their pores are filled. All stains and finishes can be used successfully.

to bring the sheen of the spring growth even with that of the summer growth.

Like pine, fine-grained woods tend to blotch - often in an unattractive way. But sometimes, as with curly, bird's-eye and mot-tled woods, the blotching is attractive. As I have described often in these pages, you can reduce the blotching by applying a washcoat (thinned finish) before apply ingthe stain, but the coloring will then be lighter.

All fine-grained woods finish well with any finish, but oil finishes require many coats for a nice appearance. Water-based finishes look wonderful on the white woods because they don't add any yellow/orange coloring, but they make cherry look washed out unless a stain is applied under the finish.

Medium-grained woods finish to look the most elegant of all woods as long as the pores are filled. This is one reason mahogany and walnut have long been considered the premier furniture woods.

All finishes except water-based look wonderful on these woods, and water-based also looks fairly good if a stain is applied under the finish.

All stains and finishes also look good on

Fine-grained woods. Woodworkers use a great many fine-grained woods. Examples include from the top: cherry, curly maple and beech. As with most fine-grained woods, these tend to blotch, especially when stained. But the blotching is often considered attractive as with curly maple. Water-based finishes look especially good on the white woods but make darker woods such as cherry look washed out unless a slain is used.

coarse-grained woods. Only quartersawn oak looks good filled. Plainsawn, coarse-grained woods look plastic, in my opinion, when filled. The filled areas are too wide.

Water-soluble dye stains don't color the pores well in coarse-grained woods. If you use a water dye, follow it with an oil-based wiping stain ofa similar color,eitherdirectly over the dye or over a washcoat, to add color to the pores.

All stains and finishes (water-based with a stain applied underneath) also look good on exotic woods. The common finishing problem with these woods is getting an oil or varnish finish (not others) to dry in a reasonable time because of the natural oily resins many of these woods contain.

To overcome the problem, wipe the surface with naphtha or acetone just before applying the first coat of oil or varnish. Then apply the finish right after the solvent evaporates off the surface. PW

Bob Flexner is author of "Understanding Wood Finishing" and a contributing editor to Popular Woodworking.

10 ■ Popular Woodworking April 2009